acevedofigueroa

A COMPARISON
OFCORAL
REEFFRONTZONATION
PATTERNS
BETWEEN
A HIGHANDANORMAL
SBDIMENT
INPUTAREAS.
by
Roberto Acevedo Figueroa
A thesís sub mitted in
partial fu1fillment of the
requirements for the degree of
MASTER
OFSCIENCE
in the
Departmentof Marine Sciences
UNIVBRSITY
OFPUERTO
RICO
MAYAGOñlCAMPUS
1986
,
Membev of the Graduate Committee
!.li<r¡f
~¿rzt;a,,,_
.3
'},(/ I
-
ge,
Date
,z-4
Presiden of the Graduate Committee ·
~h~~-
9}:om
Studi~jJ~
.~
;•
--rL
Date
~>'Jh
7
0ate
·
~ltf
i
COMPENDIO
Estetrabajo investiga la estructura de comunidades de corales incluyendo su
composición por especies, dominancia y patrones de zona.ció.o.en ocho lugares con
distintos parámetros en la costa sur de Puerto Rico. En cada lugar se recopilaron datos
mediante el uso de foto transectos en el frontón del arrecife cada cinco metros entre las
profundidades de '.5a 30 metros. La cobertura de coral vivo por especie fue obtenida
midiendo cada colonia de coral mediante el uso de un planimetro de compensación polar
e identificando cada especie por separado.
Los arrecir es de La Parguera fueron utiUzados como área control ya que estudios
anteriores demuestran que dicha área está libre de sedimentación de tipo ter.rige.na.
Debidoa que en La Parguera no existe un arrecife que sea continuo desde la superficie
--·-o
hasta profundidades de más de treinta metros. se tomaron cuatro estaciones para incluir
todas las zonas incluidas en el área de Ponce.
Los arrecifes afectados por el sedimento se encuentran en el área de Ponce, ciudad
de gran desarrollo industrial en el sur de Puerto Rico, que se caracteriza por tener una
alta sedimentación de origen ter.rigeno. El Bajo Tasmanian y el CayoCardona son los dos
arrecifes más cercanos a la fuente de sedimento, por lo que se deduce son los más
afectados. CayoRatones se encuentra un poco más alejado de la fuente de sedimentos y,
aunque presentó reducción en cobertura de coral vivo en las partes más profundas, éste
se encontró en mejores condiciones que los mencionados anteriormente. El arrecife de
-
borde de plataforma en Pe.duelas .no presentó se.dales de alta sedimentació.n ter.rige.na,
siendo sus valores de cobertura de coral y .número de especies comparables a los de La
Parguera.
Se encontró que aque11osarrecifes más cerca de la fuente de sedimentos ter.rige.nos
prese.ntaro.n me.nor número de especies de coral, me.nor cobertura de coral vivo y
cambios en la distribució.n de especies con profundidad. Estos efectos aparentemente
dismi.nuyen a medida que nos alejamos de la fuente de sedimentación. Además, se
observó que e.n areas de alta. sedimentació.n los corales constituyen sólo u.na pequeda
fracció.n de la masa arrecifa! total, siendo solame.nte aquellas especies que se co.nsideran
tolerantes al sedimento importantes en dichas áreas. En áreas caracterizadas por la
ausencia de sedimentos ter.rige.nos los corales abundan, llegándose a encontrar treinta.
y cinco especies. número que compara favorablemente con otros lugares estudiados en
el Caribe y el Pacifico.
ii
ABSTRACT
This study investigates the community structure of hermatypic coral reef s in terms
of species composition, domina.nce a.ndzoo.ation patterns from two general
enviroo.ments with different parameters. Eight sites on the south coast of Puerto Rico
were used. At each of the sites, photo transects were recorded para.lle! to depth
contours every five meters from 5 to 30 meters depth. Datawere obtained from 10 X 15
cm photos using a compensating polar pla.nimeter a.ndin.ffl:Y.
recording of species.
Selected sites at La Parguera were used as terrigenous sediment free, control reefs.
At La Parguera there are no continuous depth zones from the surface to 30 meters,
therefore four sites were picked including all depth zones utilized in this study. La
Parguera Shelf-Edge submerged reef covered from 20 to 30 m; Turrumote South East
submerged reef covered from 15 to 20 m depth, CayoTurrumote a.nd CayoEnrique
included the 5 a.nd 10 m depth zones. A11sites studied have similar substrate a.ngles to
minimize sampling error in developing a composite reef.
The other studied a.reas were located near the Ponce harbor, an a.rea characterized
by the influx of fine, terrigenous sediments. Bajo Tasma.nia.na.nd CayoCardona were
the two sites closer to the sediment source a.nd they showed the adverse eff ects of the
excess sedimentation. Cayo Ratones was farther west of the sediment source a.nd it had
much better coral cover than Bajo Tasma.nian a.nd CayoCardona. Peñuelas Shelf Edge
reef showed no signs of excess sedimentation a.nd was comparable to other flourishing
Caribbean reefs in both co.raJ.species diversity and cover.
It was found that reefs closer to a source of excess sediments showed less species
diversity, less living coral cover a.nd shifting of the depth zones to shaUower depths.
These effects apparenUy decrease with increasing distance from the sediment source.
lt was noted also that in highly sedimented a.reas corals constitute only a minor part of
the reef mass which is dominated by sponges and filamentous algae. Only coral species
classified as highly sediment tolerant were found on these reefs.
In contrast, at Peduelas Shelf Edge a.nd La Parguera reef s where sediments are
mosUy in.situ produced carbonates. conditions seem to favor the presence of
hermatypic corals with 35 species identified f rom the photographs. This is comparable
to other flourishing Caribbean a.nd Pacific reefs, despite differences in species
composition and community structure.
iii
ACKNOWLEDGEMENTS
I wish to thank the members of my committee,Dr. Jack Morelock,Dr. Luis R.
Almodóvarand Dr. Juan G.GonZálezfor their advise, encouragement and assistance.
I am especiaUygrateful to Mr. GodobertoLópezwho spent many hou.rsof travel and
diving assistance in all kinds of weather and situations; without his generosity, this
study would not have been possible. Special than.ks to M.r.CarlosGoenagaand Mr.
Vanee Vicente, feUowgraduate students, for their help throughout this study. I also
wish to thank my wife Bessiefor her encouragement and assistance. I wish to thank
the Department of Marine Sciences for the award of the assistantship that made this
study possible.
Thanks to the members of the "UnidadMarítima and Planta Física"for the use of
boats, the many hou.rs of ship t.ravel with Capt.Llndo.rfoCancel.Capt.DanielRosado,
Capt.Clarence BuUock,M.r.Enrique Cintrón, M.r.José Vargas, M.r.MarcosRosado,Mr.
Juan J.I.rizar.ry,Mr. Pedro López,and a11others who in o.neway or another contributed
to this research.
iv
TABLEOFCONTENTS
Page
List of Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
vi
List of Figures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
vii
List of Abbreviations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . viii
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1
Description of Study Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
En vironmen tal Data Review South Coast of Puerto Rico. . . . . . . . . . . .
Literature Review .............................
·. . . . . . . . . . . . . . . . . . . .
12
19
25
Methods..........................................................
Data Collection.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
25
Data Analysis .............
·. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
27
............................ ..................
30
,................
30
Species Richness. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
31
Number of Colonies. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
31
Coral Species Distribution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
35
Statistical Results of Selected Coral Cover Va1ues Between
Depth Zones . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
37
Results.............
Coral Cover .................................
Statistical Results of Selected Coral Cover Values Between
Study Sites
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Sediment Analysis Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
46
General Zonation Concepts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Zonation Patterns of Study Sites. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
La Parguera Reefs Zonation Patterns. . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Pon ce Reefs Zonation Patterns . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Invironmental Factors Affecting Reefs Zonation . . . . . . . . . . . . . . . . . 52
Sediments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
Other Factors................................................
53
V
Conclusions ......................................................
.
54
Cited Ref eren ces ..................................................
.
56
Appendix 1 ......................................................
.
62
.
83
.
89
Appendix2
.. ' ..................................
Appendix 3 ... , ..................................................
'
................
vi
LISTOFTABLES
Tables
Page
1. Numbersof CoralColo.niesfor SelectedSpeciesat StudySites
with RespectiveTotalPerce.ntCoverValues.. . . . . . . . . . . . . . . . . . . . . . . 34
Z. Scleracti.nia.nand HydrocoralSpeciesLlstwith Occurre.nce
at Each StudySite. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
3. Statisticfrom CumulativeFreque.ncyCurves.......................
43
vii
LISTOFFIGURES
Figures
Page
1. Map Showing Locations of Study Areas at La Parguera on t.he South Coast
of Puerto Rico. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3
2. CayoEnrique Bottom Bathymetry as Seen from the South . . . . . . . . . . . . . . . .
5
3. Parguera Shelf Sediment Facies Map. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6
4. Map Showing Locations of Study Areas at Parguera on the South
Coast of Puerto Rico . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7
J. Ratones-Peñuelas Depth Profiles ................
9
·.........
............
6. Pon ce Map Showing Shelf Sediment Facies . . . . . . . . . . . . . . . . . . . . . . . . . . . .
11
7. Map Showing Principal Currents of Puerto Rico . . . . . . . . . . . . . . . . . . . . . . .
16
8. Drainage of South Puerto Rico.....
..................... ..............
17
9a .. Photograph Showing Placement of Tags to Coral Colonies. . . . . . . . . . . . . . . .
26
9b. Corals Outlined and Identified from Photos.............................
26
10. Ratones Depths vs. Coral Species Diversity . . . . . . . . . . . . . . . . . . . . . . . . . . . .
32
11. Ratones-Peñuelas-Parguera
Depth vs. Coral Species Diversity . . . . . . . . . . .
33
12. Parguera Sediments Perce.nt Acid Insolubles . . . . . . . . . . . . . . . . . . . . . . . . . .
41
13. Grain Size Distributions at La Parguera and Pon ce Sediment Facies . . . . . . .
44
14. Ponce Sediments Percent Acid Insolubles . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
45
15. Cover by Species for the 10 m Depth Leyel.............................
48
16. Parguera Depth vs. Coral Species Diversity . . . . . . . . . . . . . . . . . . . . . . . . . . .
49
17a. Small Colony of Madracis decactis Surrounded by afilamentous
Algal Mat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
51
17b. Colonies of Mycetophyllia lamarckiana and Montastrea
cavernosaSurrounded by the filamentous Algal Mat...................
51
viii
LISTOFABBREVIATIONS
Species
Montastrea annularis
Montast.rea cavernosa
Agaricia agaricites
Agaricia lamarcki
Porites asteroides
Porites furcata
Porites porites
Siderastrea side.rea
Siderastrea radians
Meandrina meandrites
Colpophyllia natans
Colpophyllia breviserialis
Leptoseris cucullata
Diploria strigosa
Diplo.ria clivosa
Diploria labyrinthiformes
Stephanocoenia michelinii
Mad.racis decactis
Madracis mirabilis
Mycetophyllia aliciae
Mycetophyllia danaana
Mycetophyllia f erox
Mycetophyllia lamarckiana
Acropora cervicornis
Acropora palmata
Dichocoenia stokesi
Eusmilia f astigiata
Dendrogyra cylindrus
Mussa angulosa
Isophyllastrea rigida
Isophyllia sinuosa
Scolymia cubensis
Scolymia lacera
Solenastrea bournoni
Oculina diffusa
Millepora alcicornis
Mi11epora complanata
Millepora sgua.rrosa.
Abbreviations
M.ann.
M.cav.
Ag.ag.
Ag. lam.
P. ast.
P. fu.r.
P. por.
Sid. s.
Sid. r.
Mean. m.
Colpo. n.
Colpo. b.
Lepto. c.
Dip. s.
Dip. c.
Dip. l.
Stepha. m.
Mad.d.
Mad.m.
Mycet. al.
Mycet. d.
Mycet. f.
Mycet. lam.
A. cerv.
A.pal.
Dicho. s.
Eusmilia. f.
Dend.ro. c.
Mussa. a.
Iso. r.
Iso. s.
Seo. c.
Sco.l.
Sol. b.
Oculina. d.
Mill. a.
Mill. c.
Mill. sq.
1
INTRODUCTION
Despite the widespread attention that coral .reefs have .received, most studies have
been made on a qualitative basis; focusing on describing the distribution of coral
species. Very little work has been reported on the qua.o.titative description of these
communities. Many vital aspects of reef ecology such as species dominance,
distribution with depth, stress, mortality, a.o.dcommunity interactions should be studied
in greater detail.
Although corals do not account for the maior portian of the reef biomass, when
they die, the community degene.rates dueto the emigration of other .reef fauna. Thus
the .resistance of a reef commu.o.ityto stress can.o.otexceed that of its coral compo.o.e.o.ts.
Coral reefs are a significant resource, particularly in many developing count.ries
in the tropics whe.re they constitute the basis for local and commercial fisheries. They
are important tourism a.o.drec.reatio.o.alsites, provide protectio.o. for coastlines, a.o.d
produce calcareous sand fo.r beaches and co.o.structio.o..
These resource uses are threate.o.ed by ma.o.yman-made i.o.flue.o.ces,i.o.cludi.o.g
inc.reased turbidity and siltation, abnormal i.nputs of nutrie.nts and organic matter.
pollution by toxic chemicals and oíl, the.rmal loading, changes in water ci.rculation and
wave e:xposure, di.rect physical damage and b.reakage, a.o.dthe selective .remova1of
o.rganisms producing populatio.o.imbalances a.o.dpossibly i.o.terferi.o.gwith .o.utrie.o.t
recycling. l.o.deed,any human use of a system beyond certain limits wiU alter it unless
compensating actions are taken. The.re a.re also natural influences that ca.o.cause
cha.o.geso.o.reefs. These i.o.cludedamage f.rom waves, heavy rainfaU during storms,
u.o.usualtidal e:xposure. natural population imbala.o.cesor epidemics, a.nd even the
natural population development. successio.n or change in the system (Dahl 1980.
In o.rder to conserve this valuable natural .resou.rce,more knowledge is needed. We
must know its present state and how is it changing. and we must be able to measure the
effects of a.o.ymanagement action we may take. This study p.resents the changes that
increased sedimentation ove.r the past 25 years has brought to a once healthy and
flourishing reef area off the south coast of Puerto Rico, in te.rms of reduced living coral
cover and dive.rsity. This information can be used as a guideline to prevent further
careless reef destruction by uncontrolled deforestation a.o.dpoor land management in
order to set up provisional reef conservatio.n regulations.
· Description of Study Areas
Par1uera
Reef 1ocations and morphotogy
As sediment-free control reefs, four sites were selected at La Parguera, southwest
of Puerto Rico (Fig. 1). The La Parguera shelf edge submerged reef is located 9 km
south of Magueyes Island, site of the field station of the Department of Marine Sciences
of the University of Puerto Rico atan a.rea better known as the "OldBuoy" (17º 53' 20" N,
66• 59' SO"W]. This reef is characterized by a sand moat approximately 20 m deep
bordering it to the north, a gentle rise to the reef crest at approximately 16 m in depth,
a gradual stope to the shelf-edge at 20 m and a steeper dropoff to oceanic depths. The
slope of the dropoff is 40-45• and is further characterized by numerous sand drainage
channels that start at 18 m depth and extend to 30-35 m depth. These channels can be
up to 6 m deep and are approximately 15-20 m apart.
Turrumote S.E.is a submerged platform reef tocated approximately 5 km to the
southeast of Magueyes Island l17° 55' 35" N, 67° O' 40"W]. This site was picked to cover
the intermediate depth transect levels absent on the shelf edge and the inner La
Parguera reefs. lt also had the same substrate angle as the other study sites. The reef
rises above a broad sand and hardground platform of 20 to 24 m with a gentle rising
slope on the back reef to the reef top at approximately 13 m depth anda steeper slope
(40• ) on the reef down to 22 m depth where the sea floor 1eve1sand is covered by
fine-grained silty-sand.
CayoTurrumote Ur 56' 25" N. 67° o·59" WJis located 4 km southeastof Magueyes
Island. Its long axis is aligned east-west on a platform which was exposed some 10,000
years ago during the lower Wisconsin sealevel. This reef is surrounded by sands and
fine sediments on the north and south, a.reef a.pron lagoon with low energy wa.ve
action, and a.huge mass of dead coral f ragments that accumulated by storm activity
during the past ten years. The reef crest was dominated by Millepora.
Pa.lythoa.and
Zoa.nthus. with the reef sloping gently the first 10 m and leveling off with a moat of
mixed sediments and no coral growth. lt goes from mean sea.leve! to around 10 m
depth.
CayoEnrique (17• 57' 15" N, 67º 2' 55" WJis located approximately 0.7 km south of
Magueyes Island, running in an east-west direction parallel to the shoreline. It is
surrounded by a quiet water environment with sand and fine sediments on the north
3
Fig.
1 •
l,',ap showir1g locations
at
of the study areas
Pargu era on th e south
coast
of Puerto
Rico.
(Sathynetry
from
:fo re loe k, Go en aga
a.'ld Winget.
In press).
PUERTO
RICO
NORTH
Ü
4
and south ( Fig. 2). The uppe.r 10 m of .reef g.rowth were measured here. It is partially
protected from direct swells by two reefs to the south.
Sediment facies
Nine sedimentary facies have been distinguished in the La Parguera study area
(Fig. 3). The facies were disti.nguished o.nthe basis of grain size. percent calcium
carbonate conte:nt, and the constituent skeletal material in the carbonate fraction.
Bathymetry and location also play a role in distinguishing the facies. The outer shelf,
which constitutes more than two-thirds of the mapped area. is dominanUy outer shelf
sa:ndsor hardground. The shelf matgín is marked by an almost continuous li.ne of shelf
edge submerged barríer reefs wíth actively growing coral. The submerged coral reefs
of the outer shelf are mosUy patch reefs with massive type coral growth. The
disti.nctio.n between hard ground and reef has been made primarily on the abundan ce
of living coral. The coral reef facies on the míddle a:nd inner shelf are actively
building reefs of a platform type with an almost emergent crest of Acropora palmata
and Millepora anda reef apro.n. or bac.kreef facies of skeletal san d.
An inshore Halimeda facies composed primarily of Halimeda plates a:nd mollusc
shell fragments is found on shallow grass floored lagoons away f.rom reefs. A
carbonate-terrigenous mud facies is fou.nd o.n low ene.rgy i.nshore a.reas such as
Montalva and Phosphorescent bays and near the town of La Pargue.ra in the inner
ma:ngrove cha:nnels. A terrigenous mud facies is found on the inside of Montalva and
Phosphorescent bays.
The carbonate mud facies is primarily restricted to the La Parguera middle shelf
and líes behínd the reef lí.ne in the quíet water zone produced by these reefs. The
development of the carbonate muds is f.rom bioerosíon a:nd. precipitation of fine
carbonate by alga.e. in a deeper quiet water a.rea. of two zones protected by reef
developme:nt.
Ponce
Reef locations and mo.rphology
The study sites located in the Pon ce area were picked for the special
sedimentological conditions present (Fig. 4). Ponce is the third largest city in Puerto
5
fi g . 2 . Cayo Enrique Bottom Bathymetry as seen from the South .
Scale m meters . 3-D Topograph ic Release Program NASA
.Earth Re sour c es Laboratory, Mississippi . (Photo courtesy
of Mr . Roy Armstrong) .
6
OUTER SHELF SANDS
•
REEF
HALIMEDA NEARSRORE FACIES
D
SUBMERGEDREEFS
REEF SKELETAL SANDS
~
HARD GROUND
N
CARBONATE~fUDS
~
CARBONATEAND TERRIGENOUS HUDS
o
TERRIGENOUS l-fUDS
Figure
·3 .
P~rguera
s belf
(from Morelock,
2
km
sediment
facies
man.
Goenaga and WÍnget)
PUERTO RICO
Fig.
4 .
local ions ol lliv st11Jy
Punve 011 ll1c S()t!lli
co.::ist
Híco.
Mup !:llww_ing
¿¡ reas
of
at
Puerto
Ponce
------
··..-:--~-~---
D"-"'
RATONES
o
km
N
-.....J
8
Rico a.nd it is heavily indust.riaHzed. Extensive defo.restation during the past 150years
has increased the sediment load in rive.rs that discharge into the coastal area. A huge
amount of fine-grained terrigenous sediment has been deposited on the area just east of
the Pon ce harbor entran.ce. When onshore vinds a.nd heavy swells hit the coast, these
fine sediments a.re resuspended forming a sediment plume that t.ravels vestvard over
reef areas.
The fi.rst study site is .knovn as Bajo Tasma.nia.n [ 17° 56' 54" N, 66• 36' 42" W ] is
located east of Ponce's harbor entran.ce. It is a submerged platform reef that rises
above a fine sediment moat that borders the reef to the no.rth, east and vest. From the
reef crest at approximately 6 to 8 m deep there is a gentle slope. Belov 8 m, the
subst.rate a.ngle increases to approximately 40º for the .reef front dovn to 20 m vhere
the subst.rate levels off in a fine sediment bla.nket that bo.rders the reef to the south.
There seems to be no major sediment drainage cha.nnel system such as a spu.r a.nd
groove type morphology found on other reef areas studied. An unusually dense
population of soft co.rals (octocora.1)vas found on a.Udepth zones of this reef. The
ecological interactions that must be tak:ing place at this site are ha.rd to understand a.nd
even harder to describe.
Cayo Cardona is the next .reef site vestvard, located in front of the harbor entran.ce
[17° 57' 32" N, 66 • 37' 57" W]. It reaches the surface a.nd extends dovn to about 20m.
Subst.rate a.ngle after the reef break is around 40• f.rom 7 to 20 m. At 20 m depth the
bottom levels vhere a fine sediment cover vas found. At 5 m, the subst.rate angle is
around 10· a.nd the surface is covered by dead coral fragments of Acropora palmata.
a.nd coarse sands vith no or ve.ry fev fine sediments. High vave energies over this
part of the reef remove any fine material that setUes.
CayoRatones [ 17° 57' 10" N, 66• 40' 45" Wl is located approximately 4.5 km vest of
Cayo Cardona a.nd it is of special interest beca.use of its locally unique bathymetric
profile. This is the only reported reef in Puerto Rico that is continuous f.rom su.rface
dovn to more tha.n 50 m CFig.5). This is a better developed .reef shoving a system of
spu.r-a.nd-g.rooves fo.r sediment d.rainage starting at 10 m and going dovn to ove.r 30 m.
S1opeof the subst.rate is around 10· at '5and 10 m, increasing to around 40-45• from 15
m dov.n to over 30 m. Nume.rous fine sediment poc.kets we.re fou.nd f.rom 20 m dov.n,
t.rapped by dead coral heads fo.rming sinkholes a.nd t.rapping sediments as they settle.
Peñuelas shelf-edge reef [ 17° 56' 40" N. 66° 43' 20" WJis asubmerged shelf edge
reef that rises to approximately 15 m depth a.nd goes beyond 50 m (Fig. 5). The reef
9
Fig. 5. Ratones and Peñuelas depth profiles.
10
frontis located on the southernmost ridge of a triple ridge shelf-edge (Fig. S). and it
shows a highly developed sediment drainage system from 15 m down to over 30 m depth.
Sediment facies
The nea.rshore facies is dark terrigenous sand and mud with occasional gravel
(Fig. 6). The principal components a~ dark igneous rock fragments, mafic minerals,
quartz, and plagioclase feldspar. Gravel sized pieces of igneous rock fragments are
plates dominate the
reHct. The texture is dominatly mud in protected areas. Hali.meda
carbonate sand grains, with spicules and moUusk fragments common. The carbonate
sediments are mainly from Thatassia meadows and small f ringing reefs which
generaUy constitute less than 25% of the total sand. The beach sands are igneous rock
fragments and mafic minerals with minor amounts of quartz and feldspar and less than
10%carbonate grains except at El Tuque beach where carbonate grains are 25% of the
beach sands (Beach, 1981).
Pon ce Basin extends from the Caja de Muertos fault to about three kilometers west
of the Pon ce Harbor. It is floored with fine terrigenous muds and some carbonate muds.
The basin sediments are poorly sorted silts and clays with small amounts of carbonate
sand that ha.ve been carried in from surrounding areas and ha.ve accumulated in low
energy, deeper water conditions. Similar sediments floor Pon ce Submarine Canyon.
The northern part of the basin is dominated by dark to olive terrigenous muds. More
carbonate mud contribution is found in the southern basin. Beach (1981) measured 65
to 70 cm of these muds lying over a calcareous sand, showing a change in the
depositional environment. Measurement of sediment accumulation on an artificial reef
near Ponce gave an accumulation rate of 4 mm per year for the terrigenous muds
(Beach, 1981). Applying this rate to the accumulated mud blanket, shows that it could
ha.ve been deposited during the last 125to 150years. Land stripping for sugar cane,
urba.nization, a.nd dredging for harbor facilities could account for increased erosion
a.nd the development of this mud accumulation.
These fine sediments are resuspended by va.ve action and ship traffic. The
resulting visibility in the water column is less than 1 m (pers. obs.). This develops the
sediment plume that is tra.nsported by west-northwest a.nd northwest currents,
carrying fine sediments over the reef s.
The outer shelf sands are biogenic. They are poorly sorted a.ndare produced in.
situ. Current velocities are low. so most reworking a.nd tra.nsport is due to biological
-~~~-:--~~~~~~~~---.
•
NEARSIHiRE ZONE
lilil
~
,•
SHELF BASIN
illZ1
OUTER SHELF
UVE REEFS
D
SANl'LE COI.LfC'l' llJN S J 'l'E
TRANSECT Sl'J'E
N
NEARSHOREZONE-Dark-gray
silt
und fine su,~,
preduminuutly
SHELF BASlN-Silt
and e lay, <l,n:k-gruy
an<l predu111iuuut 1 y lerr
in the ,rnuth.
OUTER Sl!ELF-Biogenic
LIVE REEFS-Biologically
·"?t~!~í}
O
J
...
' --
terrigeuuus
igenous
in
2 km
.- J
but includes
biogenic
grains.
lhe nut-ll,,
] ight-coJ
oncd bi ogeni e
coarse
sun<l and gruvel,
wilh ca.lcu,-eou,;
alga]
nodules
constructed
n,efo
\vÍlh active
reef
frumework
coral
Figure.
6
l'once mup slwwlng
(f nirn Acevedo,
,;helf
~,-t:Kf~
cadnllld
Le
co111111011.
growth.
s;edi111ent faci.es.
Morelock
élnd
Ol ivieri
in
press)
l--1
.....
12
activity. S.teletal particles are coralline algae, mollusc fragments and
Hatimeda.
Sediments with the carbonate platfo.rms and .reefs a.re biogenic sands and gravels with
the same constituents. Most of the material is moved f.rom the .reefs by wave action. and
do not accumulate in deeper water because of the s1ope. Howeve.r,sediment filled
pockets are common on Ratones reef.
Envi.ronmental Data Review: South Coastof Puerto Rico
Climate
In general, the climate of Puerto Rico is typically tropical marine. That is, du.ring
the day, as the land mass heats up, a convection cell is developed causing the winds to
move landwa.rd from the sea, bringing the moist sea ai.r with them. In the evening, as
the land cools, the convection ce11reve.rses and the winds btow offshore. Due to the
nume.rous hills and mountains on the island of Puerto Rico, the moist sea air is
f requenUy cooled to satu.ration while still ove.r the land mass. This causes considerable
.rainfal1 almost daily ove.r some parts of the island. In summary, the meteo.rological
conditions fo.r the coasts of Puerto Rico a.re as follows:
The.re is no summe.r and winter. but simply a change from wet season to a
somewhat drie.r season. Ai.r temperatu.re varíes within a mean daily .range of 10 to 15•F.
fluctuating between the tow 70's and the 1owSO'sfrom December through April and
between the mid 70's and the upper SO'sfrom May th.rough Novembe.r. The lowest value
.reco.rdedat San Jua.n I.nte.r.natio.nalAi.rpo.rtwas 60.1• F.
P.rotonged i.nte.rvals of either su.n.ny, ctoudless weathe.r o.r completely ove.rcast
weather a.re u.nusual. The commo.nco.nditio.nis parUy cloudy, in which the cumuli
occupy between 40 to 60 percent of the sky, .relative humidities are high du.ring the
enti.re year, usually ranging between 65 and 85 percent. Only .rarely does the .relative
humidity drop below 50 pe.rcent. Dense fog is seldom seen. Squalls and thunde.rsto.rms
a.re common f.rom May th.rough November.
For tropical marine a.reas, atmospheric p.ressu.re changes are no.rmally very small.
Changes of 5mm of mercury overa couple of months a.re rare. However, the proximity
of severe tropical weathe.r, such as tropical dep.ressions, sto.rms, o.r hurricanes, could
cause large d.rops in the atmospheric pressure. These pressure changes, in tu.rn, are
instrumental in controlling the local sea level. As the sea level is changed by such
13
pressure disturbances, deep water is brought up toward, and in some cases. to the
su.rface (adapted from_Morelock et. al., 1985).
The tides on the Caribbea.n coasts of Puerto Rico are gene.rally of the mixed diurnal
type, with a sma11semi-diurnal componen t. Two waves exist, but one is dominant for
about ten days, followed by about four days of neap tide co.nditio.nsas one wave
decreases in amplitude and the second wave builds. Then the second wave builds. Then
the second wave is dominant for about ten days (U.S. Naval Office Oceanographic Atlas
of the North Atlantic Ocean, 1%5).
Wind Regime
The U.S.Coastal Pilot, Area 5 (U.S.Dept. of Commerce, 1976), summarizes the wind
regime on the coasts of the island as fo11ows.
"The prevailing winds over Puerto Rico are the E trades,
which generaJly biow fresh during the day. The center
of the Bermuda High shifts a little N in summer and S in
winter changing the direction of the wínds over that
island f .rom NNEin winter to E in summer.
Factors which interrup the trade wind flow are frontal
and E wave passages. As the cold front approaches, the
wind shifts to a more S direction, and then as the front
passes there is a gradual shift through the SWand NW
quad.rants back to NE. The E wave passage normally does
not bring a Wwind but is usually characterized by an
ENEwind ahead of the wave and change to ESEfollowing
the passage.
Over most of the ocean near Puerto Rico the strengh of
the winds in creases in mídsummer, with lighter winds
in the sp.ring and autumn seasons. The.re are also
somewhat highe.r average winds in the NWpa.rt of the
a.rea in the late autumn and winter. Mean wínd speed
ove.r the Atlantic in this a.rea .range from '4.5to 5m/sec
during the autumn to a high of 6 to
8m/sec in midsummer."
Winter-su.mmer summa.ry and monthly wind roses for the Caribbean Sea,
respectively, as ext.racted from the U.S.Naval Office Oceanog.raphic Atlas of the North
14
Atlantic Ocean. Sectíon IV (1%3). indicate that east wínds .ranging from 2 to 14m/sec
p.redominate du.ring the summe.r ove.r the NEwínds. Du.ring the winte.r season the NE
winds become stonge.r than, and almost equal in frequency to, the E winds (37% to 44%,
.respectiveJy). Wind di.rections f.rom the N and SE are more frequent du.ring the winte.r
than wave .regime patte.rns ove.r the sea. as shall be shown in the discussion of the
díffere.nces in the sea-state conditions du.ring winter and summe.r. Du.ring the wínte.r
months (January, Feb.ruary, Ma.rch) winds in the no.rth and no.rthweste.rn quad.rants
a.re evide.ntly abse.nt. In the sp.ring and autumn seasons the.re a.re gradual. weak
va.riations f.rom these di.rectio.ns the east wínd aJways predominanting
in st.re.ngth with
a frequency ra.nge of about 30 to 60 percent of the time du.ring the year.
The most freque.ntly occurri.ng wind speeds lie between 5 to 8m/second, occur.ring
37.3% of the year. Wind speeds between 3 and 1lm/ sec occu.r 7).7% of the year and
indicate the p.redomina.nce of mode.rate wind speeds in the study area. High wind
speeds in excess of 14m/sec occur only 0.4% of the year. The average wind speed is 6
m/sec. Winds exceed l8m/seé about 0.1% of the time, o.r a.pproxima.tely 9 hours ayear.
Hurricanes
The characte.ristics of hu.r.rica.nes reaching the United States have been
intensively studied, but similar info.rmatio.n is .not available fo.r hu.r.ricanes at lowe.r
latitudes. The study sítes He somewhat along the hur.ricane t.rack as the sto.rms t.ra.nsit
westwa.rd f.rom the Atla.ntic to the Gulf of Mexico.
Some informa.tion about hurricanes affecti.ng the study site can be determi.ned
f.rom the U.S. Dept. of Commerce .review of major hu.rricanes between the years 1873
and 1%7. Duri.ng these 94 yea.rs, there we.re 94 hu.r.rica.nes repo.rted at anave.rage of
one hur.rica.ne per year. The.re were 30 hurricanes during the 94-year period that
passed withi.n 100 km of the South Coast.
The mean .recurren ce inte.rva.J fo.r hu.rricanes strongJy affecting Puerto Rico is
about 1 per 3 yea.rs. These storms, however, a.re not uníformly dist.ributed ove.r the
years. In someyears (1933 and 1955) two hurricanes
occu.rred in one year. During
some other pe.riods, no hu.rrica.nes occu.r.red fo.r many years.
15
Waves
The most frequently occurring wave height is in the interval of .3-.8 m occur.ring
41% of the year. At La Parguera, a study of wave characte.ristics discerned two distinct
wave sets: one with a period of S to 8 seconds and significant wave height of 62 to 147
cm anda second with a period of 4.seconds anda height of 27 to 74.cm (Lugo, 1982). A 6
second, 85 cm height wave has been reported in other parts of the Caribbean. The wave
can be identified as trade wind generated. The smaller wave is a locally generated wave
which fits a hindcast for a mean wind speed of 5 m/sec. 7 hour duration and 90 km
fetch. Wave height on the south coast of Puerto Rico exceed 300 cm only 0.5 percent of
the year. Wave heights over 5 meters recur about once every three years and waves in
excess of 8 meters recuron the average of one every 100years (U. S. Naval Office Ocean
Atlas of the North Atlantic Ocean. 1965).
Currents
Predominant surface currents on the south coast of Puerto Rico run westward
parallel to the coast for most partofthe year, CFig.7). The westsetting North
Equatoria1 Currentflows past the Lesser Antilles and through the Caribbean, (U. S.
Naval Office Ocean AUasof the North Atlantic Ocean. 1965). Only occasionally, and for
sho.rt pe.riods of time, the cur.rents flow to the south o.r southeast. lt has not been
established what causes this shifting in direction. Cur.rents are gene.raly associated
with tidal exchange and they vary from weak to strong, Colón (1971).
D.rainage
Figure 8 shows the principal .rive.rs that flow to the south coast of Puerto Rico. R.io
Jacaguas and R.ioDescalabrado are the principal .rivers aff ecting the study area at
Ponce, they reach the coast east of Ponce harbor entrance and contribute substantia11y
to the terrigenous sediments found in the Ponce basin and inner shelf deposits.
Longshore cu.rrents move sediments westward to the reef a.reas.
At La Pargue.ra, occasional .runoff is the only local sou.rce of te.r.rigenous
sediments, sin ce no rivers are present in the a.rea. During .rainstorms, dense flows of
mud washed from the soil cover are seen diffusing offshore and are very dense
adjacent to the tidal flats and inner mangrove channels.
N
-----.,,.
,_
__
....
-------.,.--
/
/
1
seasonal
currents
.......
...,
'
.,;
\
'
PUERTO RICO
~
FIG. 7
Map showing principal surface currents of Puerto Rico.
r-'
O'\
17
/
o
<J
c2
o
...
a."'
::,
=
o
::,
(J)
o
"'
...
>
"'
(I)
·;:
(!)
·o
e:
¡;: ¿
18
Turbidity
A significant variation in water transparency was observed a.mong the study sites.
At Pon ce, water transparency was lowest at Bajo Tasmanian and Cardona. Sechií
readings averaged 3.5 m. Ratones averaged 8 m and Peñuelas Shelf Edge 18 m. La
Pargue.ra Shelf Edge readings exceeded 25 m, Tu.rrumote S. E. averaged 15 m and at
Turrumote and Enrique the Sechií disc reached bottom at 12 m without disappearin.g.
Transparency is estímated to be around 14 to 15 m.
19
LITERATURE
REVIEW
The distribution of scleractinian corals on coral reefs has been related to a variety
of factors including depth, light. slope of the substrate, sedímentatíon, wave energy
and biologicalinteractions (Yonge,1930; Stoddart,1969;ConneH,1973;Glynn,1973a). The
dominan ce of species in certaín habitats is often explained by circumstantial evidence.
Whereas the physical environment (waves, cur.rents, tida1 exposure) has a strong
influence over coral distributions at shallow depths, biological processes ( competition,
predation, bioturbation. and symbiosis) take on an. increasing influence in the deeper
reef ( Glynn 1976). Discussion of the role of physical and biological disturban ces in
structuring coral communities may be found in Grassle (1973), Loya (1972) an.d Porter
(1974). Bak (1977) has suggested that interspecific differences in the mechanism of
recruitment, dispersa! a.nd morta1ity of juveniles ma.y be of prima.ry importance in
determining the composition of species assemblages of corals in different habitats.
Desc.riptive studies on local species composition an.d general distribution are found
for various parts of the Caribbean including Curacao (Bak,1976) an.d other Netherlan.ds
Antilles (Bak,1977). Ma.rtinique (Adey and R. Burke 1976), Puerto Rico (Almy and
Carrión.1963), Jamaica (Goreau an.d Goreau 1959a,b, Goreau and Wells,1967),Panama
(Dana.1976), Anegada, British Virgin Islands (Dunne and Brown 1979) and Cuba
(Duarte-Bello,1961;Zlatarsky and Martinez.1982). Colín (1978) provided in place color
photographs of most Caribbean he.rmatypic co.rals and othe.r organisms which are
useful for identification purposes.
Recent quantitative studies carried out on the community structure, ecology and
diversity of coral reefs in the western AUantic region in elude: the Caribbean. (Milliman
1973). the San Blas islan.ds on the Atlantic coast of Panama (Porter,1972), Bonai.re
(Scatterday.1974), Barbados (Lewis 1970,Ott 1975) an.d Netherland Antilles (Roos 1971).
Very few studies have been carried out on the deeper parts of reefs and those are
timited to deep fore-reef slopes an.d have been predominantly carried out in Jamaica.
off Discovery Bay Marine Laboratory. These i.nc1udeGoreau 0959). Go.reauand Go.reau
0959 a,b), Goreau and Goreau (1963), Goreau an.d Wells (1967), Goreau an.d Land (1974),
Lang (1974). Recently, with the use of submersibtes, the deep base of reefs an.d the
tower limit of coral growth have been studied more extensively (James and Ginsburg
1979,Hartman,1973 an.d Porter, 1974).
Numerous methods for surveying sessile benthic communities have been employed
in characterizing coral reef community studies. Many methods are simp1y refineme.nts
20
of ea.rlie.r methods whe.re mo.re specialized o.r quantitative data have been desi.red o.r
whe.re local conditions impose .rest.rictions on the way data can be collected.
The fi.rst use of a photog.raphic method in coral .reef surveys mentioned in the
literature was in a study on reef zonation at Aldabra atoll in 1968-1969CDrew,1977).
Drew discussed this method. including its limitations and possible improvements.
Bohnsack (1979), evaluated 35mm. color photography as a quantitative sampling
technique for hard bottom benthic communities and concluded that cover was a
valuable community parameter that could be accurately quantified, computerized and
be statistically tested. It does not disturb the organisms and provides a permanent
.record.
Weinberg (1981) made a compa.rison of coral reef survey methods based on the
number of species observed, relative coverage in percent, and population densities. He
concluded that the best methods were the in.liw. drawing of quadrats anda
photog.raphic record of .reef sections. The disadvantages he found were the time
consuming task of dra.wing reef sections and the high expenses of subma.rine
photographic equipment. Dodgeet. al. 0982). compared in quantitative terms four
survey methods at each of three reef sites. Three plotless a.nd o.ne quadrat method were
employed. Each technique gave good results, but had inherent advantages and
disadvantages which involve trade offs i.n qua.ntity, type of informa.tion, and time
consumption.
Boulon (1980) studied the community structure of hermatypic cora.ls in terms of
species composition, zonation, a.nd diversity at two sites on the shelf edge submerged
reef at La Parguera., Puerto Rico. He used a photo quadrat method with p.rojection
analysis using random points on a screen .
The line t.ransect method, which is the basis of the photographic transect method,
was probably first used by Mayor (1918) in hiswo.rk on the structu.re and ecology of
Samoan .reefs. It was used simply to record the numbe.r of coral heads along the
t.ransect. A refinement of this method, which yields much more quantitative data, was
used by Loya 0972) in the Red Sea. Porter (1972) further refined this technique using
a chai.n-Hnk counting method used to record both the number of species and thei.r
relative abundance to be measured.
Few studies deal with the effects of turbidity and sedimentation on the growth of
reefs. Turbidity increases light attenuation and thereby decreases photosynthesis by
symbiotic zooxanthellae (Goreau 1959,Muscatine 1979), calcification rates are
diminished as well. After temperature, light is probably the most impo.rtant limiting
21
factor to coral reef growth. 'Active coral g.rowth is g.reatly diminished in deeper parts
of .reefs (Rosen 1971) and does not occur be1owdepths having 15 to 20% of su.rface light
values (Lang 1971). Goreau and Goreau 0959 a,b) examined the .rate of grovth of .reef
building corals by measuring the rate of calcium deposition in the s.keleton using the
calcium 45 technique. It was possible to measure the calcification rates in díffere.nt
pa.rts of the colonies and to estímate quantitatively the effects of light and darkness and
ca.rbonic anhydrase inhibitor on skeletogenesis under labo.rato.ry conditio.ns and also
in the field. For most species, there was a signíficant in crease in calcificatio.n rates on
exposu.re of the coral to light. Coral bleachi.ng caused the rate of calcium deposition to
'
fal1 drastically. The g.reatest dec.rease occurred when corals were .kept in dar.kness in
the presence of a carbo.nic anhydrase inhibitor.
Reef-building corals live between the ocean's surface and 100 m. and are subject to
a photic e.nvironment in which there is considerable variation in both intensity and
spectral quality (Jerlov 1%8). While individual "adult" co1onies a.re sessile th.roughout
their lives, members of the sam.especies may inhabit depth ranges as great as 95 m.
(Goreau and Wells 1%7) suggesting that the zooxanthellae within the same species of
coral are able to photosynthesize overa wide .range of light intensities and spectral
qua1ities.
It is believed that all zoo:xanthe11aefrom hermatypic corals are the same species,
Gymnodinium mic.road.riadicumFreudentha1, Taylor 0%9). However, evidence of
physiological variabilíty wíth .respect to photoadaptation has been presented by
Lelet.kin and Zvalinsky (1980. Titlayanov (1981), Drew (1973) and Lang (1973). Lang
demonst.rated, th.rough t.ransplantation of coral colonies f.rom the deepe.r habitats of the
reef to sha11owerwater, that the zooxantheHae have restricted abiHties to adapt to
sudden in creases in light intensity. The results of her experiments showed that the
response to transplantation differed between species and that the rate of bleaching was
p.roportiona1 to the increment in light intensity. Thus, the zooxanthe11ae of deep water
corals are unable to change their photophysio1ogica1 machine.ry rapidly to adapt to
sudden in creases in light intensities. A similar response was observed on th.ree coral
species after a d.rastic reduction in light intensity afte.r a tropical rainstorm on a
no.rma11ywe11-illuminated reef off southwest Puerto Rico (Acevedo and Goenaga in
press).
It is conceivable that variation among zooxanthellae could lead to some of the
for
diffe.rences in ske1etal morphology and behavior that have been used as criteria
distinguishing species of coral (Goreau 1959; Lang 1973; Wells 1957). Corals that enjoy
22
large vertical depth distríbutíons exhibit the general. though not universal trend of
skeletal flattening with increasing depth and in shaded habitats (Goreau and
Goreau.1963). The Hmits of this general trend are a sphere a.nd flat plate (Barnes 1973).
This cha.nge in skeletal morphology seems to be the result of a decreasing calcium
carbonate deposition rateas a direct consequence of decreasing zooxanthellae
photosynthetic activity (Goreau 1959).
Dustan (1979) suggested the existen ce of two ecotypic races of zooxanthellae in the
Montastrea annularis popu1ation on Dancing Lady Reef, Jamaica. One adapted to high
light conditíons above lS to 20 m. and the other to lower intensity light conditions
be1ow20 m. The two populations ovedap to the extent that flat colonies are sometimes
found on shallow shaded habitats.
The systematic varíations of zooxanthellae density and photosynthetic pigments
suggest that as water depth in creases the zooxanthellae become more efficient at
absorbing the available light energy (Muscatine 1980). However efficient the energy
capture becomes, it appears that eventually the coral becomes light limited.
Photoadaptatíon of the zooxanthellae may permit the coral to extend its depth range.
Whe.reasdec.rease in photosynthesis is a natural consequence of in crease in depth.
there is evidence that coral respiration also decreases. Davies (1977) investigated intra
and interspecific variation in coral respiration as a function of depth using
transpla.nted specimens of Montastrea cavernosa and Montastrea annularis collected
from 2 to 40 m. The.re was evidenee that transplanted Montastrea changed the
respi.ration rate to conform to the new depth in about 5 wee.ks,suggesting that the
corals were responding to environmental factors.
Some other important effects of sedimentatío.n o.n coral reefs are; smothe.ring of
the coral surface (Roy and Smith 1971).inhibition of larval settlement (Wells 1957).
abrasion of coral coloni es and .reduction off eeding time due to stimulation of polyp
contraction (Levin 1971). Corals .remove sediments by tentacular and ciliary action,
body extention a.nd mucus sheetentanglement (Hubbard 1973. Bak and Ege.rshuizen.
1976) but aH of these .rep.resent an e.ne.rgy drai.n on the corals. Roge.rs (1977) showed
experimentally thát reduction of incide.nt light by suspended sediments has a greater
effect on some coral species than the sedime.nt itself. Whatever the mea.ns of action the
results of high sediment loading appear to be the .reductio.nof co.ral growth rates (Aller
and Dodge 1974).depressed spa.t .recruitment. and sometimes coral death (Roge.rs 1977).
In the Ca.ribbean and WestAUantic region. severa! authors have recognized a coral
fauna characteristic of areas with high rates of sedimentation. Corals such as
23
Montastrea
cavernosa. Diploriastrigosa.
and Siderastrea siderea which domínate this
fauna are frequently of secondary importance on other reefs. These have been
characterized as eff ective sediment removers by Loya ( 1976) and Lasker ( 1980). Loya
reported that water turbidity and sedime.ntatio.n seemed to be the major factors that
dictate the distribution of corals in different reef zones. He compared tvo reef areas
with diff erent sedimentological conditions and foun:d that high coral cover and higher
diversity occurred i.n the sedime.nt-f.ree reef and low coral cover with low diversity
occurred on the highly sedimented reef. Loya (op. cit.) attributed the diffe.rences i.n
commu.nity structu.re betwee.n these reefs to turbidity and sedime.nt input. Montastrea
cavernosa was the most abunda..nt species and the ma.jor f.ra.mebuilder in the highly
sedime.nted .reef. M. cavernosa reflects most of the morphological fea.tu.res typical of
corals ha.ving grea.ter efficie.ncy in sediment .rejectio.n (Lasker 1980).
Exposure of reefs to silt-lade.n wa.ters associa.ted with flood runoff seems to be a
majorca.use of reef destruction historically. Blasting and dredging of channels for
passage of ships through the reef is a.widespread but seldom documented source of
sedimentswhich pollute the reef community. Marzale.k (1981) andThompson (1979)
have studied the effects of dredging on corals reporting reductions or complete
destruction of the coral community. Although corals can cleanse themselves of
moderate amounts of sediments, most cannot live for long if heavily coated or buried
(Marshall and Orr 1931).
Moreloc.ket. al. (1977, 1979) studied the structure of severa! reefs off LaParguera.
and Guayanilla., Puerto Rico and developed a concept of zonation for the reefs of the
area. and described changes on zonation ca.usedby sedimentation. Goenaga and Cintrón
( 1979) enumera.te the reefs of Puerto Rico a..ndlisted those found to be most affected by
sedimentation or other problems. Weiss a.nd Goddard 0976) describe some of the
disasters that urbanization brought to a once healthy and flourishing reef in
Venezuela.. All of the Acropo.ra pa.lmata were killed a.nd the Acropora. cervicornis
colo.nieswere seriously affected, along with the corals in the massive coral zone. The
subst.rate was cove.red by a.thin algal mat and fine sediment. Cortés a.nd Risk ( 1985)
found that the .reefs at Ca.huíta,CostaRica showed low coral cover and diversity with a
large average colony diameter, the amou.nts of suspended particula.te ma.tter were very
high a.nd a.large amount of terrigenous material was t.rapped betwee.n coral heads.
Coral growth ra.tes were found to be low. The increase in sedimentation vas attributed
to recent deforestation that has occurred during the past 15 yea..rson the coast of Costa
Rica..
-------------~---~-~
-
--
--
~---
24
High islands and continental landa.reas f.ringed by .reefs are frequently a.reas of
high .rainfa11with lush vegetation and a.re thus pa.rticula.rly susceptible to erosion
after the .remova1.of cove.r. Kirby (1%9) stated that the g.reate.r the rainfa.11and the
thic.k.e.rthe vegetatíon, the greate.r the acceleration of e.rosion resulting f.rom the
stripping of the vegetation.
Although co.rals do not account fo.r the majo.r fraction of total .reef éommunity
biomass, when they die, the community degene.rates and soon the associated reef fauna
either dies or emig.rates, thus the resistan ce of this community to environmenta1
st.resses cannot exceed those of its coral components. Recupe.ration is improbable
because once corals die, thei.r su.rfaces a.re rapid1y colonized by filamentous algae
making it impossible fo.r cora11a.rvae to setUe (Chesher 1%9b). The .response of .reef
communities to anth.ropogenic activities ispoo.rly understood, the information available
on the toleran ce and effects of pollution on reef co.rals should be used as a guideline fo.r
setting up provisional conservation .regu1ations (Johannes 1970).
25
METHODS
Data Collection
Field Methods
Photo-transects were picked as the most accurate and efficient reef survey method
after reviewing discussions by Bohnsack (1979), Weinberg 0981) and Dodge et. al.
(1982). Photo-transects were made parallel to depth con tours at 5. 10, 15. 20, 25. and
30 m depths on reef fronts with similar slopes to eliminate any bias from slope
variation. Each transect consisted of three randomly located chains: each chain was
15 m long and was marked every 1.5m. A photo was ta.ken at each mark covering O.7
sq. m each for a total of 7.7 sq. m per chain. A transect covers 23 sq. m at each depth.
Loya (1972) determi.o.edthe mínimum length for a within habitat sample to be 10 m.
Fourteen transects were made on Pon ce reefs and ni.ne transects at La Parguera for a
total of 759 photos coveri.ng approximately 531 sq. m. This provides adequate coverage
of the reef front in the mixed, massive, a.nd Montast.rea-Agaricia. zones. Sínce the
shallow (0-4m) Acropora palmata zone is extremely se.o.sitiveto hurríca.ne damage, it
has not been considered in this study due to the recent severe effects of hurricanes
David, Federick in 1979,and Allen in 1980which destroyed most of thiszone. Recovery
is still in complete and hurricane effects create another variable.
A Ni.konosIV-A camera with electronic strobe and ASA-100color film provided
positive identification of coral colo.nies. Numbered tags were placed on each coral
colon y, and identified in situ (Fig. 9a). Distance between substrate and camera was
maintai.ned constant by framing previously measured sections on the chai.n.
Alignment was such that the chain ran through the center of the photograph.'s long
axis.
Sediment was collected from sediment pockets and drainage chan.nels for analysis
at each transect site. The use of sediment traps was not possible because of difficulties
in finding them again. It was assumed that there is a relationship between the amount
of terrigenous sediment trapped on reef poc.k.etsand the amount of terrigenous
sedimenta reef receives.
26
fig 9a . Photograph
showing placement
of tags to co ral co lonies
f ig. 9t> . Corals outline<l an<l i<len tifie<l from photos .
27
Data Analysis
Photo analysis
Each photog.raph was analyzed by outlining each co.ral colony and identifying lts
species acco.rding to the number tag it was given in the field survey. Subsequently,
with the use of a compensating polar pla.nimete.r the a.real extent of each colony was
measu.red and .reco.rded(Fíg. 9b). When a coral lacked a numbe.r tag, the identification
was made acco.rdi.ng to its appeara.nce a.nd mo.rphological characte.ristics anda lette.r
was assigned to it. Colonies cut by the photo's edge we.re measu.red usi.ng only the area
inside the photo. A ha.nd held magnifier aided in positive identification if the.re was
any doubt. The percentage of unidentified or misídentified corals is assumed to be
insignificant sin ce the difficult ones to identify were small colonies of usually less
than one pe.rcent of the a.rea in a photog.raph. Fo.reach photo the total coral a.rea units
for each species is .reco.rded and divided by the photo's total units ( for a 10 X 15 cm
photo= 1.500units). AHa.rea units far each species on the 11 photos that comprise a
chain are added and divided by total cha.in.photo units (16,500). This gives a fai.rly valid
idea of the reef composition in total pe.rcent coral cover, percent cover by species,
diversity index, and dominan ce patte.rns. The use of three chains allowed statistica1
evaluation of similarity patterns within one reef ata specific depth which can then be
pooled and compared to other .reefs with similar physical and topographic conditions
but diffe.rent sedimenta.ry envi.ronment.
The sho.rt cut analysis of va.rían ce test developed by Link and Wa11ace(1952) was
pe:rfo.rmedon coral cove.r results in orde.r to detect significant differences in species
dist.ributions with depth and between study sites. Sin ce some coral species domínate
ce.rtain depth zones and are absent on othe.rs, they we.re selected a.rbítrarily according
to their a.hundan ces. The sho.rt cut ANOVAassumes normal, equally variable
populations and uses the range to set confidence limits. It is applicab1e to one-way
classification.s, each group of the same size. A 5% confidence limit was picked in o.rder
to keep the rejection of a true null hypothesis or Type I error ata safe level. This
method has been proven efficient in detecting diffe.rences between any two totals o.r
mean s.
28
Sedimen.tanalysis
Sediment was collected from .reef pockets and o.r sediment d.raínage channels as
available at all survey depths levels. Analysis of each sa.mplewas performed using
Folk's ( 1974) method for grain size analysis. Each sa.mple was passed through a 4 0 wet
sieve mesh to separate the san.d and grave! f.raction from the silts and clays. The coarse
fraction was then dried and sieved using half-phi i.nterval screens. A Ro-Tap vibrator
was run for a period of 10 minutes, then each fraction were weighed to .001 gram with
a p.recision balance.
The silts and clays were washed with distilled water to remove a.Usalts for pipette
analysis. The sa.mple was pou.red into a 1000m1.cyli.nde.rand water plus the dispersant
was added to b.ring the volume to 1000ml: then it vas sti.rred a.nd let stand for 24 hours.
The samples that showed signs of floculation were discarded and a new sample vas
processed. Ea.ch cylinder vas stirred vigorously unti1 all material vas distributed
evenly th.rough the column. At exactly 20 seconds a pipette was inserted ata depth of
20 cm. and 20 ml. sample extracted. After 2 hrs. 3 mins. another 20 ml. sa.mplewas
withd.raw.n at 2.5 cm. depth. The sa.mpleswere poured into pre weighed 50 ml. beake.rs
and dried at 100-130• C. Then they were removed and cooled at room tempe.ratu.re in a
dessícato.r, then allowed to come into equilibrium with the moistu.re content of the
laborato.ry atmosphe.re.
Grain-size dist.ribution of a sediment, and the statistical paramete.rs which describe
that distribution a.re determined by: ( 1) the size and sorting of the sediment supply,
and (2) the velocity, turbulence, and othe.r cha.racte.ristics of the agents of t.ranspo.rt in
the environment of deposition.
Statistical para.meters of size distribution aUow quantitative comparison of one size
distribution with another. These sta.tistical parameters in elude measures of average
size or central tendency, sorting or spread about the average, skewness or the measure
of the asymmet.ry of the distribution, and kurtosis or peakedness of the size
dist.ribution.
The most useful measures of central tendency o.raverage size are the mode and
mean. In a perfectly symmet.rical dist.ribution these are identical, but they are not the
same in most sediment distributions. The median is probably the most frequently used
measure sin ce it is the easiest to compute, being simply the 50% value, but its value as a
statistical para.meter is questio.nable.
29
The modal sjze is the grain sjze at the high point on the frequency distribution
curve. It represents the most abundant grain sjze in the sediment. If there are two
high points separated by a saddle. the distribution is bi.modal;if seve.ral. it is po1ymoda1.
The mode, because it represents the most common grain sjze in a sediment, has a fairly
important physica1 meaning.
The mean sjze is the average obtained by summation and division. An approximate
or graphic mean can be obtai.ned from the cu.mmulative frequency curve (Folk, 1974).
The mean as derived from the method of moments is affected by every particle in the
sjze distributíon.
Measu.res of the so.rting o.r degree of spreadin grain-sjze distributions include the
standard deviation. range and othe.rs. The standard deviation is a statistica1 measure of
the dispersion of s.izevalues about the mean. About two-thirds of the sample is within
one standard deviation on either side of the mean on a normal distributíon. Like the
mean. the standard deviation is tedious to calculate, but an approxímate or graphíc
standard deviation can be obtained from the cumulative frequency curve.
Sorting of a sediment (as measured by o.ne of the parameters discussed) depends
u pon: (1) the sjze range of the material supplied to the environment: (2) the ene.rgy of
the environment of deposition and (3) the characte.ristics of the curren t. Currents
with constant velocity give better sorting than fluctuati.ng o.r highly turbulent
currents. Sorting is generaly best Ín medium to fine sands and beco.mespoo.re.ras the
sediment beco.mescoarse.r or fine.r. Poor so.rting may also reflect contributions from
multiple sources.
The acid insoluble content of sedíments was computed for the total and fo.r the fine
fractions of each sample in o.rder to detect which fraction of the sediment had the
greatest acid insoluble componen t . .Eachsample was dried and weighed, then using 10%
HCLacid, all carbonates were combusted. After a11acíd was removed, the resídues were
redried and weighed again.. The acid insoluble .residues we.re assumed to be the
te.rrigenous fraction of the sediments that reached the reef. The carbonate fraction of
the sample is the amount of reef s.keletal material and muds deríved from bioerosion or
in situ production. How much carbonate material is transported from terrestial sources
is not known but it is assumed to be insignificant when compared to reef carbonate
production.
30
RESULTS
LaParguera
Living coral cover was computed for all sites using photo transects at available
depths where any coral growth occurred. At La Parguera Shelf Edge, the mean value
for coral cover at 20 m was 43.3%. At 25 m, coral cover was 50.1% and at 30 m a total of
41.3% was computed. Foresreef po.rtions of the reef showed trends of increasing cover
towards the edge with a maximum reached immediately behind the edge. Percent
coverage falls off rapidly with depth below 36-37 m. A deep dive at this site revealed
that coral is living at depths exceeding 60 m. Mean values for perce.nt coral cover for
15and 20 m depths at Turrumote South East were 16% and 21.4% respectively.
CayoTurrumote mean coral cover values were 7% for 5 m depth and 22% for the 10
m level. This fow value for the 5 m level could be attributed to the effects fromrecent
hurricanes, which destroyed almost all of the shaHow coral, piling huge amounts of
coral debris on the reef crest and back reef areas.
Enrique coral cover values were 25.1% for 5 m and 24.3% for the 10m depth level.
Enrique reef was partially protected from hurricane waves by two reefs to the south of
it, Cayo Laurel and Arrecife Media Luna.
Pon ce
At Bajo Tasmanian, the 10 m depth leve! hada mean coral cover value of 5.8%,
decreasi.ng to 3.2% at 15 m depth. CayoCardona had only 0.5% mean living coral cover
at 5 m depth increasing to 3.9% at 10 m and no coral growth below 12 m. The substrate
showed evidence of big dead coral heads as deep as 20 m. These were covered by a thin
filamentous algal mat that trapped fine sediment and ímpedes coral larvae seulement.
CayoRatones at 5 m depth, hada 6.2% mean live coral cover value, 9.9% for 10 m,
12.7%for 15 m, 6.9% for 20 m, 4.8% for 25 m and only .1% for 30 m depth, no living coral
was found deeper than 35 m and, there was evidence of huge dead coral heads covered
by a filamentous algal mat similar to the one observed on Cayo Cardona.
Peñ.uelas Shelf Edge gave a total percent living coral cove.r of 30% at 15m depth.
The 20 m depth level hada total coral cover of 24%, 18%for the 25 m level and 8.2% for
31
the 30 m depth level. A deep dive at this site showed that coral was living in depths
exceeding 50 m. No filamentous algal mat was present on this reef.
Species Richness
At La Parguera Shelf Edge, a total of 21 species were found at 20 m, 20 species at 25
m and 19 species at 30 m. At Turrumote South East, a total of 12 species at 15 m and 1'f
species for the 20 m depth were found. CayoTurrumote hada total of 8 species at 5 m
increasing to 18 species at the 10 m depth level. This large difference is probably
caused by two important factors, first the shallower parts of this reef were severely
affected by hurricanes David, Frederic.k.and AUen in 1979-1980and stiU have not
recovered completely; secondly, variation of coral distributions between reef sites on
Turrumote is enormous with some parts showing better coral growth than others.
Since sa.mpling sites were pic.ked randomly, this could have been the .reason fo.r such a
low value in species numbe.r. At CayoEnrique 13 species were found at 5 m and 16
species at the 10 m depth level.
At Pon ce, the total numbe.r of scleractinian coral species follows a similar t.rend to
that of coral coverage. On most sites, species numbe.r reaches a maximum that declines
both with increasing depth or turbidity. Major cont.ributo.rs to the reef st.ructure
varied f rom site to site as some species seemed better adapted to turbidity and low light
1eve1sthan others: also some species seem to be better adapted to higher wave energies.
The 10 m t.ransect at Bajo Tasmanian gave a total of 12 coral species and 11 species for
the 15 m level. Cayo Cardona at 5 m depth hada total of 3 species and 9 species at 10 m
depth. No living co.rals were found at 15 m. At CayoRatones, 9 species were found at 5
m, 14 species at 10 m, 13 species at 15 m, 11 speciesat20 m, 7 species at25 m and only 2
for the 30 m depth leve! <Fig. 1O). Peñuelas Shelf Edge had a total of 17 species for the
15 m depth leve!, 16 species at 20 m, 18 species for 25 m and 11 fo.r the 30 m depth
transect <Fig. 11 ).
Number gf Colonies
Total number of colonies for each species was computed from t.ransects at each
study site. (Table 1). Some species, i.e. Acropora cemcornis form dense branching
thic.k.etsin which it was impossible to distinguish separate colonies from the
photographs, each agg.regation was t.reated as one colony for consistency.
32
fig. 10. Ratones Depth vs. Coral Spedes Diversity
14
12
10
Number
of Coral
Species
8
6
4
2
o
5m
10 m
15 m
20 m
Depth
25 m
30 m
33
Fig. 11. Ratones- Peñuela.s- Parguera Depth vs. Coral Species Diversity
ITDRatones
Number ot Coral
~ Peruielas
Species
~ Parguera
15m
20m
25m
Depth
30m
34
Table 1. Numberof Coral Coloniesfor Selected Species at Study Siles tiith RespectiveTotal Cover
Values.
BA(O TASMAN!Af:!
5m IOm 15m 20 m 25 m 30 m
Total Colonies Total :t Cover
M. ann.
2
2
4
J.8
M.cav.
29
26
55
4
Ag. ag.
6
11
<O.l
P. ast.
2
3
,O.l
.5
Sid. s.
8
8
16
0..5
Mean.m.
3
2
5
0.5
A. cerv.
l
o
l
0.1
CARDONA
M.ann.
o 3
3
0.l
M.cav.
o 21
21
2.5
Ag. ag.
o 4
4
<0.1
P. ast.
o 3
3
<0.l
Sid. s.
7
11
18
O.J
Mean.m.
o 4
'
~
M.ann.
M.cav.
Ag.ag.
Ag. lam.
P. ast.
Sid. s.
Mean.m.
PE8UELAS
M.ann.
M. cav.
Ag. ag.
Ag. Jam.
P. ast.
Sid. s.
Mean.m.
PARG!.!W S-1;;
M.ano.
M. cav
Ag. ag.
Ag. lam.
P. ast.
Sid. s.
Mean.m.
TURRUMO]]
S-~
M.ann.
M.cav.
Ag. ag.
P. ast.
Sid.s.
Meam.m.
13
21
42
.57
2
7
o
o
31
6
27
1.5
o
J
~
M.ann.
M. cav.
Ag.ag,
P. ast.
Sld. s.
A. cerv.
<j
13
12
7
76
42
93
o
.S4
18
ll
2
17
88
12
3
13
'I
69
44
163
6
44
1.5
13
0.6
o
o
o
o
o
94
99
233
62
79
.53
13
7.7
5.3
8
.5.7
2.9
2.2
0.6
28
29
186
6
4
177
129
.531
29.4
5.9
17.8
0.9
3.6
3.5
2.1
10
<!2 4
o
.5
7
o
1
o
23
17
16
14
89
33
o
l
3
45
121
51
43
198 231 97
42 25 34
200 245 252
o 2 22
94 81 37
IJ
4
'I
19 10 6
526
101
697
24
212
19
3.5
64.7
7.9
36.2
4.5
57
47
66
27
14
7
136
82
120
71
<!O
19
1J.4
10.4
5.5
2.8
2.1
<!7
10
'19
12
14
10
49
10
49
97
28
IOA
80
15
J
JI
23
8
7
2
106
95
12
79
3.5
.54
.¡.¡
26
12
TUl!l!!.!M9IE
M. aon.
M. cav.
Ag. ag.
P. ast.
Sid. s.
A. cerv.
.S8
38
71
4
2
o
o
8.5
14
4
JI
18
11
14
129
19
25
13
8
J.4
2
l
2.2
2.1
.,.6
l.9
2.1
21.9
J.3
10.2
1.1
2
4.7
35
~ Soecies Distributions
A total of 34 scleractin.ian corals, and 3 hydrozoan species were identified from all
transects (Table 2). Of these, 28 species were found at La Pargue.ra She1f .Edge,18 at
Tu.r.rumoteSouth East. 21 at CayoTurrumote, 21 at CayoEnrique. 17 specíes at Bajo
Tasmanian, 11 species at Cayo Cardona, 21 at CayoRatones, and 23 species at Peñuelas
She1f.Edge.
Montastrea annularis. Montastrea cavernosa. Aga.ricia agaricites. Porites
asteroides.
Siderastrea
siderea.Meandrina
meandfites.
Dioloríastrigosa
Stephanocoenia michetinii. Madracis decactis. and the hyd.rocoral Millepora alcicornis
were species common to all study sites.
Combining aHdepth leve1 transects, the corals that co.ntribute to the bulk of reef
mass in terms of percent cover. in order of importan ce a.re: 1) At La Pa.rguera Shelf
Edge Montastrea annularis. Montastrea cavernosa. Aga.ricia agaricites. Aga.ricia
lama.rck.i.Porites asteroides. and Mea.ndrina.meandrites a.re the most important reef
contributors. 2) Montast.reaannula.ris. Montastrea cavernosa. Porites asteroides.
Sidecastrea siderea. and Colpophyllia nata.ns
a.re major reef contributo.rs at Tur.rumote
South East. 3) Montast.rea annula.ris. Montastrea cavernosa. Porites asteroides. Agaricia
agaricites. Acropora palmata and Colpophyllia natans a.re major reef builders at Cayo
Turrumote. 4) At CayoEnrique. the most important reef contributors a.re: Montastrea
annulafis. Aeariciaa¡aricites.Acrooora
cecvicornisColpoohyllia nataos.and
Siderastrea siderea. S) AtBajo Tasmanian Montastrea annula.ris. Montastrea cavernosa.
Dendrogyra. cylindrus. Siderastrea siderea. Meandrina meandrites. and Aga.ricia
aga.ricites. 6) At Cayo Cardona Montastrea cavernosa. Montastrea annularis and
Meandrina meandrítes. 7) At Cayo Ratones Montastrea
annulafisMontastrea
cavernosa. Agaricia agaricites. Agaricia lam.a.rc.ltiand Porites asteroides a.re the major
reef builders. 8) At Peñuelas Shetf Edge; Montastrea annu1aris. Montastrea. cavernosa.
Aga(icia agaricites. Porites asteroides. Siderastrea siderea. and Agaricia lam.arc.ki.
(Appendix 1).
Some species showed dominan.ce at certain depth zones and these varied from site
to site as weU. These va.riations could be dueto differences in light levels between
depth zones and also between sites as water transpa.rency varied greaUy am.ong study
sites changing illumination intensities reaching the substrate.
36
Table 2. Sc1eractinianand HydrocoratSpecies List with Occurrenceat eacb Site.
Species
Site I
M.ann.
M.cav.
Ag.ag.
Ag. lam.
P. ast.
P. por.
P. fur.
Sid. s.
Sid. r.
Mean.m.
Co1po.o.
Colpo.b.
Lepto.c.
Dip. s.
Dip. c.
Dip. 1.
A. cerv.
A. pat.
Stepba.m.
Mycet.1.
Mycet.r.
Mycet.a.
Mycet.d.
Dicho.s.
Sol. b.
Mad.d.
Mad.m.
Dendro.c.
Iso. r.
lso. s.
Seo.c.
seo. 1.
Mussa.a.
Eusmilia. r.
MiU.a.
MiU.c.
MiU.sq.
TOTALS
Site II
Site III
Site IV
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
SlteV
Site VI
X
Site VIII
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Site VII
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
17
l1
X
X
X
X
X
X
X
X
X
X
21
23
28
X
X
X
X
X
18
X
X
X
21
21
LEGEND
OFSJTES
Site I
Site II
Site III
Site IV
BajoTasmanian
CayoCardona
CayoRatones
PeftuelasSbetf Edge
Site V
Site VI
Site VII
Site VIII
La Parguera Sbetf Edge
TurrumoteSouthEast
CayoTurrumote
CayoEnrique
37
Statistical
ResultsQf Selected ~ ~ YaluesBetween
Ilemh.~
A short cut one way analysis of varian ce test was performed for selected coral
species at each transect depth 1eve1. A 5% risk factor was selected to detect statistically
valid differences between depth zones. In this procedure we run the risk of making
one or more incorrect conclusions in 5 experiments per 100.
At La Parguera Shelf Edge, Montastrea. annularis, the major reef contributor, was
fou.nd to be sig.nificantly higher cover o.n the 25 m depth as compared to the 30 m depth
leve l. The 20 and 30 m cover values were not significantly different. Montastrea
cavernosa. was found to be notsig.nificantly different between depth zones. Agaricia
agaricites cover value at 20 m was sig.nificantly higher than the 25 and 30 m depth
values. Porites asteroides value for 20 m was sig.nificantly higher than the 30 m depth
level sin ce no colonies were found at 30 m depth. Siderastrea. siderea distribution was
significantly differe.nt between the 20 and 30 m depth levels as this species is greatly
reduced in number after 25 m depth.
Turrumote South East coral cover values for Mo.ntastrea a.nnularis were .not
sig.nifica.ntly different between the 15 and 20 m depth zones. Montastrea cavernosa was
not significantly different between the 15 a.nd 20 m cover values. Agaricia agaricites,
Porites asteroides and Siderastrea siderea cover values were not sig.nificantly different
betwee.n 15 a.nd 20 m depth zones.
At CayoTurrumote. the major co_ntributors for reef mass. Agaricía agarícites.
Porites asteroides. Siderastrea siderea and Acropora palma.ta we:re not sig.nificanUy
different between the 5 and 10 m depth zones. At CayoEnrique, Agaricia. aga:ricites
cover value was found to be significanUy different between 5 and 10 m depth levels.
Montastrea annularis.
Montastrea cavernosa. Porites asteroides and Siderastrea síderea
we:re .not significantly differe.nt betwee.n the 5 and 10 m depth levels.
No sig.nificant differe.nces in the dist:ributions of Agaricia a.garicites, Porites
asteroides. Montastrea annuJaris, Montastrea cavernosa and Siderastrea siderea were
detected between the 10 and 15 m depth leveJs at Bajo Tasmanian. CayoCardona showed
no significant differe.nces in the distribution of Siderastrea siderea.. the o.nly
sig.nificant coral species found at 5 and 10 m depth levels. At CayoRatones, the 15 m
Montastrea annularis percent cover was significantly higher than the 25 and 30 m
depth values. Montastrea cavernosa at 5 m was significanUy different from the 10, 15,
25 and 30 m depth 1eve1s;this coral was a major reef builder at 10 and 15 m, but was
greaUy reduced or abse.nt at 5, 20, 25 and 30 m depth levels. Aga.ricia a.garicites was
38
significantly higher at intermediate depths ( 15, 20 m) ,as compared to deeper parts of
the reef (25 and 30 m), but it was not significantly different from the 5 and 10m depths.
Porites asteroides was significantly higher at 5 and 10 mas compared to the 20 and 25 m
depth zones. The 15 m depth level was not significantly different from the 5. 10.20. 25
and 30 meters depth zones. Siderastrea siderea was not significantly different between
depth zones.
At Peñuelas Shelf Edge, the 15m depth level value for Montastrea annularis was
significantly higher than the 25 and 30 m depth leve1s. This species vas greatly
reduced after 25 m depth. In 15and 20 m depths, cover values for Montastrea
cavernosa were significantly higher than the 30 m depth leve! value.
Statistical Results of Selected Coral Cover Values Betwee.nS!Y.gySites
S m Depth Level
Montastrea annularis. had significantly higher cover values at CayoEnrique
compared to CayoRatones, Cayo Cardona and CayoTurrumote. Montastrea cavernosa
cover was not significantly different between sites fo.r the 5 m depth level. Agaricia
agaricites cover values were significantly higher at CayoEnrique than at CayoRatones,
Cayo Cardona and CayoTurrumote . Siderastrea síderea, and Porites asteroides cover
palmatawas
values were not significantly different between study sites. Acropora
found at CayoTu.rrumote, CayoEnrique and CayoRatones with cove.r values .not
significantly different. No living colonies of Acropora palmata was found at Cayo
Cardona.
10 m Depth Level
Montastrea annularis cover values for Bajo Tasmanian, CayoRatones, Cayo
Turrumote a.nd CayoEnrique were .not sig.nificantly díffere.nt. CayoCardo.navalue was
significantly lower than CayoTu.r.rumotevalue. Montastrea cavernosa cover values
were not significa.ntly diff erent between study sites. Aga.ricia agaricites cover values
at CayoEnrique were significantly higher compared to Bajo Tasma.nian, CayoCardona,
CayoRatones and CayoTurrumote. Po.rites asteroides cove.r va1ues were significantly
highe.r at CayoRatones as compared to Bajo Tasmanian and Cayo Cardona. Values for
CayoRatones were not significantly different to the values found at CayoTurrumote
39
and CayoEnrique. Siderastrea
sidereacover value was not significant1y different
between study sites. Colpophyllia natans cover values were found to be significantly
higher at CayoTurrumote as compared to Bajo Tasmanian. CayoCardona and Cayo
Ratones. but .not sig.nificantty differe.nt to the CayoEnrique cover value.
15 mDepth Leve!
Montastrea annularis cover value was significantly higher at Peñuelas Shelf Edge
as compared to Bajo Tasmanian and Cayo Cardo.navalues. but not significantly different
to Turrumote South East value. Montastrea cavernosa cover value was not sig.nifica.ntly
different between study sites. Agaricia agaricites cover values at CayoRatones and
Peñuelas Shelf Edge were sígnificanUy higher compared to Bajo Tasmanian, but not
significa.ntly different to the Turrumote South East value. Porítes asteroides value at
Peñuelas ShelfEdge was significantly higher than Bajo Tasmanian, but not
significantly different to CayoRatones and CayoTurrumote South East values.
Siderastrea siderea cover values were not significanUy different between study sites.
Co1ooohy11ia
natanscover value
for Peñuelas Shelf Edge reef was significantly higher
than at Bajo Tasma.nian and Cayo Cardo.na,but not significantly different from the
Turrumote South East cover value.
20 mDepth Level
Montastrea an.nularis cover value at La Parguera Shelf Edge was significantly
higher than all other study sites. Peñuelas Shelf Edge cover was sig.nificantly higher
cavernosa at Turrumote South East had
than the CayoRatones value. Montastrea.
significantly higher cover value than CayoRatones, Peñuelas Shelf Edge and La
Parguera Shelf Edge values. Agaricia agaricites values were not significanUy diff erent
between sites. Porites asteroides cover value at La Parguera Shelf Edge was
sig.nifícantly higher compared to CayoRatones and Peñuelas Shelf Edge, but was not
sig.nificantly different from the Turrumote South .Eastvalue. Siderastrea siderea was
.not sig.nificantly different between study sites.
40
25 mDeoth Level
Montastrea annularis cover value for La Parguera Shelf Edge was significantly
higher than Cayo Ratones and Peñuelas She1f Edge values. Montastrea cavernosa cover
value at La Parguera Shelf Edge was significa.ntly higher compared to CayoRatones
value. Agaricia agaricites values at Peñuelas and La Parguera Shelf-Edge were
significantly higher than CayoRatones value. Agaricia lama.rcki cover at Cayo
Ratones was significantly higher compared to La Parguera Shelf Edge and Peñuelas
She1f Edge. Porites asteroides cover at Parguera Shelf-Edge was significan.tly higher
than CayoRatones and Peñuelas Shelf Edge. Siderastrea siderea values were not
significantly different. Meandrina meandrites cover values at La Parguera Shelf-Edge
and Peñuelas Shelf Edge were not significan.tly different, but they were significantly
higher compared to the Cayo Ratones value.
30 mDepth Level
Montastrea annu1afis cover value at La Parguera Shelf-Edge was significantly
higher than CayoRatones and Peñuelas Shelf Edge. Montastrea cavernosa value at
Parguera Shelf Edge was significantly higher to CayoRatones and Peñuelas Shelf Edge
values. Agaricia. agaricites cover values at Peñuelas Shelf Edge and La Parguera Shelf
Edge were significantly higher than at CayoRatones. Agarícialamarckícover values
were not significantly different between study sites. Madracis decactis was not
significantly different between study sites.
Sedíment Analysís Results
LAParguera
La Parguera sediments showed small amounts of acid insoluble residues suggesting
little influence of terrigenous sediments sources (Fig.12). AH study sites had less than
10 percent fine-grained particles with the exception of Turrumote S-Eat 20 m where
more than 34 percent fine-grai.ned carbonates were found. These probably origi.nated·
on she1f patch reefs south of the site and were transported by waves a.nd currents
(Appendix 2). Moderate sorting values for the La Parguera Shelf Edge samples suggests
41
fig. 12. La Parguera Se<liments Percent Ac1<l Insolutles
( Total Sa.mple)
Enrique 1 O m.
5m.
Turr.
Sfü,
10-m.
15 m.
·~~~-~
Turr. S.E. 20 m.
20 m.
25m .
Old Buoy 30 m .
......_~.....,._;~..Jlo....Jl....:i
.t::~~¡::=~ti~=-----+--------1
o
2
4
6
% Acid lnso lub les
8
10
12
42
that .rewo.r.kingof sediments occu.rs as they move down the shelf edge th.rough
sediment d.rainage channels.
At CayoEnrique, CayoTurrumote a.ndTurrumote South East, sorting values we.re
found to be .ranging from poorly to ext.remely poorly so.rted (Table 3). So.rting values
were classified according to Folk ( 1974). Grain size analysis for La Parguera sediments
gave similar results between sudy sites. Most samples at La Parguera had more than
92% sa.n.dswith very few silts (Fig.13).
The g.rain size analysis results for the Pon ce sediment samples varied g.reaUy
between reef depth zones and between study sites. The shallow water samples showed
.reduced amounts of fine-g.rai.ned sediments due to higher wave ene.rgies that resuspend
and remove fine particles away from the area. Deeper parts of the reef had more
fine-grai.ned terrigenous sediment particles.
Bajo Tasmanian had considerable amounts of fine-grained sediments with very
poorly sorted sediments suggesting contributions f.rom bottom terrige.nous and
carbonate sources. At 10 m, average grain. size was coarser than at 15 m due to the
higher energy 1eve1at sha11ower depths which removed sma11e.rparticles.
Cayo Cardona sediment samples gave a similar cumulative frequency cu.rve to Bajo
Tasmanian (Appendix 2). At 15 m, the grain size is .reduced considerably and the acid
insoluble residues increased substantially showing the presence of fine-grained
terrigenous particles Cfig.14). The shallower depths have much less fine-grained
pa.rticles as higher wave ene.rgies wash them out. CayoRatones sediments also showed
an in crease in fine-grai.ned terrigenous sediments at deepe.r parts of the reef where
wave ene.rgies are .not strong enough to flush them out.
Peñuelas Shelf Edge sediment samples showed very litUe acid insoluble residues
and coarser grain sizes even at the deeper parts of the reef indicating that very Httle
terrigenous sediments reached thís area. Sorting values for Pon ce sediment samples
ranged from poorly to ext.remely poorly sorted.
43
Table3. Statístícsfrom CumulativeFrequency
Curves
MEAN
BajoTasmanian
10m
15m
Cardona
5m
10m
15m
Ratones
Sm
10m
15m
20m
25m
30m
Peñuelas
15m
20m
25m
30m
PargueraS-E
20m
25m
30m
TurrumoteS-E
15m
20m
Turrumote
5m
10m
Enrique
5m
10m
MEDIAN
STO.DEVIATION
( SORTING)
Classífícation
5
5.3
5.3
6.1
3.7
very poorJysorted
very poorJysorted
0.6
0.2
4.6
0.6
0.2
5.1
1.6
1.3
3
moderately
sorted
moderately
sorted
very poorJysorted
0.2
0.3
0.1
4.2
3
4.7
4.2
2
1.6
3
3.3
3.1
3.6
poorly sorted
moderate
Jysorted
very poorJysorted
very poorJysorted
very poorJysorted
very poorJysorted
l. 1
2.7
2.3
2
2.3
very poorJysorted
very poorJysorted
. poorJysorted
very peorly sorted
l. 1
1.3
1.1
1.2
1.2
l.2
l. 1
moderately
sorted
moderately
sorted
moderately
sorted
0.1
2.7
0.3
2.5
2
3.6
poorJysorted
very poorJysorted
0.7
0.6
0.7
0.3
1.3
1.2
moderately
sorted
moderately
sorted
0.2
0.4
0.8
3
2.5
very poorJysorted
very poorJysorted
o
3.8
3.3
4.3
4.1
1.2
0.3
0.8
0.6
1.1
0.4
0.8
0.5
2.9 .·
44
Pon ce
Clay
,::,
Mixed
Sand _____
=
s_il_t_y_s_an_<l
___________
Clay
La Perguera
Sand _____
Silt
·=
s_u_t_y_s_an_<l
___________
Si1t
Fig. 13. Grain Size Distributions at Ponce and La Perguera
45
fig. 14. Pon ce Se<limen ts Percen t Acid Insol ut>les
Site
O
1O
20
30
40
50
60
70
80
90
100
% Acid Insolubles
(Total Sample)
15mll••••
20m ·-----•••
25m ..
·------·
Peñ.30m
111111111111111111111111•
5m
1Om bICilI(Ill][m[m[m[Il)J[Il]J[]]]J[lll)
15m
S it e
ILU.li.l.li.lLUJLLIJLLIJL.UJL.UJL.UJLI.Lu.Lll.l.ll.l.ll.Lll.Lll.L.lll
2 Om JU.ULLU..LU.ll.LJ.Ull.L.&.U.&.U.li.l.li.l.Ll.llil.ll
25m JLU.li.lLUJLU.ILLIJLLLILLLIL!.Lu.LLLl.u.Llllll.Lll.LJ.U.&.U..LU
Rat. 30m lIJ[IIlllIJ[lDiliaIJllIID[IIlllllaIJllll
5m ¡...,o;..s..4., ....... -'"'--'.....:.~L.G
1Om ,._......'--"-..............
-..- ...........
._....
..............
....._~
Card. 15m 1-L-'--'-'-'-'-'-'-LJ.:...L.LJ.:...L.~:...L..L.-o~..c....~..L.,c....c...L-c....c...L-LJ
10m ,....~'"'""""'""....."""'"""""'.:...:..=--'-'=""""'.;.;..:....:.....:~=.:..:...i.:.i.'-'..;..:.'-"-'-...:.:....:..1
8. T. 15m :;::::::::::::::::·::::::
..-·-:·:·:::::.::::::::::-:=:=:=:=:::::::::::::::::·:::::=.=:=:=:::::::=:=:::::::::::::::::::=:
o
10
20
30
40
50
% Acid Insolubles
(Fine Fraction)
60
70
80
46
DISCUSSION
Gene.ral Zonation Concepts
The living .reef front has a structu.red zonation which can be seen in both ancient
and modern .reefs. Zonation and changes in the coral cover are responses to energy
inputs and natural stress in the environment. There is a horizontal change in the .reef
community and sedimenta.ry p.rocesses that is .related to lee and windwa.rd position on
the reef. We can distinguish forereef, reef crest, baclc reef and 1agoon environments.
The basic forereef changes with depth are from ·rapid growíng, branching coral to
massive coral coJonies, and then to fragile, platy corals.
The zonation boundaries cannot be dete.rmined by community structure alone; the
morphology of the bottom, the g.rowth fo.rms of the colonies and othe.r physical and
bíological factors influence the composition and distribution patte.rns of the coral
community. It is important to note that .reefs subject to high sedimentation show
diff erent coral dist.ributions when compared to norma11y sedimented reefs.
Zonation Pattecns Qf 1M.Study ~
La Parguera Reefs Zonal.ion Patterns
La Pargue.ra .reef c.rest is dominated by Millepora. Pajythoa and Zoanthus species.
The reef crest is the most exposed and of necessity, the most wave resistant part of the
.reef. It is continuous along the 1ength of the .reef, and usua11yhas a .raised outer lip.
The Ac.ropora palmata zone extends from the surface to three o.r four meters depth.
This zone disappears or is severely limited in extent as sediment input in creases. Also
hu.rricanes David and Frederick in 1979and A11enin 1980eliminated most of this zone
on exposed reefs at La Pargue.ra. This zone is also restricted to relatively clear water
with mode.rate to strong wave energies. Acropora palmata dominates to such an extent
that coral diversíty is low despite the high leve! of coral cove.r. The 1owe.rpart of this
zone is often patterned into a spur-and-groove configu.ration is reponse to wave
energíes. Difficulties in sampling this area plus the eff ects of hur.ricanes o.o.this zone
are reasons for not conside.ríng it in this study.
The second reef zone, the mixed cora1zone is gently sloping, coral heads a.re
.relatively small and soft corals are sometimes abundant. This zone is dominanted by
47
Montastrea annularis.Acropora cecricornís. Agaricia agaricítes. Co1pophy11iana_tans.
Porites asteroides. and Siderastrea siderea (Fig. 1)). This zone probably exists because
of the development of a marine terrace during a period of halt in sea level rise. Its
presence could be the result of a change in substrate slope as the insular shelf was
in.undated and corals colonized this newly available areas. In places. the coral becomes
so sparse that the assemblage approaches a hard ground facies.
A break in the slope occurs between the mixed coral zone and the third coral zone.
the massive coral zone. Coral species in the massive zone grow on a relat.ively steep
slope and are dominated by Montastrea annularisMontastrea cavernosa, Agaricia
agaricites. Porites asteroides and Colpophyllia nata.ns.
There is no continuous section of this zone at La Parguera. The upper part of the
zone ends at 12 to 14 meters on the emergent reefs and the lower part of the reef forms
a sand and grave! fore reef talus zone. The lower part of the massive coral zone is
found at Turrumote South Eastsubmerged reef and atLa Parguera Shelf-Edge reef.
This is the zone of greatest coral species diversity found at La Parguera (Fig. 16). The
depth range of the zone marks a fairly rapid change in light penetrat.ion anda major
reduction in the presence of branching coral, except for some deeper level bottom
communities of Acropora cervicornis at La Pa.rgueraShelf Edge reef.
At 22 to 25 meters the composition of the reef community changes and another
coral zone can be distinguished, the platy coral zone dominated by Montastrea
annularis and Agarica agaricites. Pocites asteroides. and Monta.strea cavernosa are
secondary in importan ce. Although Agaricia agaricites is found in all other coral
zones, there is a change to dominance. and to a more delicate, platy growth form. Both,
Montastrea annularis and Agaricia agaricites have a platy shape at depth in contrast to
their shallow water hemispherical forms. This zone occurs on a relatively steep slope.
the coral cover is reduced, and the colonies are separated from one another in contrast
to the close crowding of the massive zone. This zone can be distinguished in other
Caribbean reefs. At 30 meters depth, Montastrea annularis a.nd Agarica agaricites sti11
dominate coral cover but Agaricia lamarcki begi.ns to gain importan ce as a reef
contributor.
Ponce Reefs Zonation Patterns
Bajo Tasmanian and CayoCardona are both, excellent examples of chronic
sediment conditions. On both sites Montastrea cavernosa dominates total coral cover,
48
Turrumole1O m. % Coverby Species
Olher
Enrique1O m.%CoverBy Species
M.cav.
P. asl. Other M.cav.
Colpo.n.
A carv.
2 4%i:otal-Coral
Cover
21.7% TotalCoralCover
canbna IO m. i <mer By Species
BajoTasmanian1O m. % Coverby Species
Mean.m.
Sid.s.
M. ann.
Den.c.
3.6? TotalCoralCover
M.ann.
5.5%TotalCoralCover
Ratones1O m.%CJ:Ner By Specles
M.cav.
Ag.rq.
9.5%TotalCoralCover
Fig.
15.
Cover by Species
M.ann.
for the 10 m Depth Level.
49
fig. 16. La Parguera
Area Depth vs. Coral Species Diversity
25
Shelf-
Edge
20
Shelf-
Edge
Shelf-
25m
30m
Turr.
Turr.
15
Edge
Turr.
S-E
S-E
Number oí Coral
Species
1o
5
o
5m
10m
15m
Depth
20m
20m
so
Montastrea cavernosa is consídered one of the most sediment resistant specíes of the
scleractinian corals (Lasker 1980,Loya 1976). The morphology of this species with its
high polyp relief makes it an efficient sediment remover. Although percent cover
values for Montastrea cavernosa are .aot significa.aUy different to La Parguera values.
the absence of other coral species suggests its ability to tolerate higher sediment levets.
No living Acropora palmata colonies were found at CayoCardona suggesting that
sedi.ment input is too high for this sedi.ment-sensitive corals. At Bajo Tasmanian,
Agaricia lamarcki,a deep reef coral. was found at 15 m suggesting that light reaching
this depth is .reduced. At CayoCardona. no living corals were found deeper that 12 m
suggesting that present conditions were not suitable for coral larvae settlement.
CayoRatones also showed the eff ects of above normal sediment i.nputs especially at
depths below 15 m where wave action does not remove sedime.at partides and where
the water column is sufficiently deep to reduce the light penetration. Montastrea
cavernosa dominated the 10 m depth leve! and was an important reef builder at 15 m.
Below 15 m, platy corals dominated the reef com.munity; a sign of adaptation for
maxi.mumlight gathering. A hummocky forereef morphology is noticeable composed
of huge dead coral heads covered by a thin filamentous al gal mat ffig. 17a). At 25 m
o.nly four corals species are p.resent in appreciable amounts but only the species
Agaricia lam.arcki is co.mmon. At 30 m only Aga.ricia lamarcki and Madracis decactis
were found and in reduced amounts (Fig. 17b).
At Peñuelas Shelf-Edge, zonation patte.rns were completely different; coral was
very abundant at 15 m and below, species dive.rsity was high, and coral morphology was
of a hemisphe.rical. massive type. Montast.rea annula.ris do.minated the 15 and 20 meter
depth levels and Montastrea cavernosa was common. At 25 m depth Agaricia agaricites
was the dominant species with Montastrea annularis as the second main contributor.
At 30 .mAgaricia agaricites a.nd Agaricia 1amarcki dominated. Eleven other species
were found but only in s.ma11a.mounts. This site was ve.ry similar to La Parguera Shelf
Edge reef in terms of coral d.ist.ributionpatterns and coral species diversity. Total coral
cover was higher at La Parguera for the 25 and 30 m depths, this was attributed to
differences in water transparency between these sites.
51
fig 17 a . Small co lon y of Madrac1s decact1s surrounded
algal mat . Area to the nght shows a sediment drainage
Cayo Ratones JO m depth.
t>y a filamen taus
channel .
fig 17 t>. Colonies of M:-1-ceto~hy:!lialamar ckian a and Montastrea
caverno sa surrounded by an al gal mat. Cayo Ratones , 20 meters depth .
52
Environment Factors Affecting Reefs Zonation
Sediments
Pa.rgue.ra
Study sites at La Pargue.ra had smaU amounts of te.r.rigenous sediments, because
the.re is no sou.rce in the vicinity of .reef a.reas. Te.r.rigenous sediment facies are
.restricted to very small inshore protected channels and embayments where wave
action is baffed by mangroves. Carbonate muds were found on middle shelf reef areas,
but these seem not to affect reef development adversely. These carbonate muds a.re
p.roduced f.rom bioe.rosion. bo.ring. p.recipitation by algae and othe.r physical o.r
biological p.rocesses.
Reduced coral cover at reefs near the source of terrigenous sediments suggests
that the influx of terrigenous sediments was an important factor contributing to the
dete.rioration of these .reefs. The fact that Bajo Tasmanian had a highe.r coral cover and
species dive.rsity as compared to Cayo Cardona suggested that resuspension of bottom
sediments of the Pon ce Canyon by ship traffic caused a deterioration of conditions at
Cayo Cardo.na. Pon ce reefs, influenced by the terrige.nous sediments, showed decreased
coral cove.r, lowe.r species diversity and .reduced vertical coral growth zones as
compared to La Parguera reefs. At Peñuelas Shelf-Edge reef, where we found little
terrigenous sediment i.nflux, co.nditions were similar to La Pa.rgue.ra reefs. Coral
species diversity and cover was high; the lower limit of coral growth was greater than
60m.
The depths to which living coral can be found is .related to the amount of sediment
in the water column. Clear reefs as found in Belize, Jamaica, and the Bahamas, have
living coral to depths of 110 meters, and at La Parguera Shelf Edge off southwest Puerto
Rico, six miles from an arid shore, there is living coral past 70 meters.
The effects of sediment stress on coral a.re diff e.rent in the cases of ch.ronic o.r
episodic sediment influxes. The effect of sediment stress is less seve.re when the stress
occurs for short periods of time and with infrequent occurren ce. Chronic stress with
53
almost daily resuspension or ínflux of sedíment results in severe loss of living coral.
even when there is less total sediment load. The death of a reef system from sedíment
stress proceeds in a series of steps: 1) lowered light input due to water turbidity causes
shifts in the ecological pattern and depth limits of the branching coral 2) direct
deposition on coral heads results in selective loss of coral related to the tolera.nce of
individual coral to sediment loading 3) a loss of total coral cover and a shift to slower
growing coral occurs, with a modification of the deep water coral assemblage 4) dead
coral areas are covered with a.nalga! sedime.nt mat, reduci.ng space for colo.nizatio.nj)
co.nti.nuedstress reduces the cover from 30 to 40 percent down to less than three
percent, and the number of species from more than 20 to less than five.
Other Factors
Other factors that i.nflue.nce reef zo.natio.na.nd coral distributio.n i.nclude: 1)
hurricanes that destroy sha11owe.rparts of emerge.nt reefs, 2) Mass mo.rtality of the
u.rchin Diadema anti11a.rum. caused an algae prolif e.ratio.nwhich competed with corals
a.nd other reef fauna for available subst.rate. 3) sewage a.nd fertilizer pollutio.n i.nc.rease
nut.rients on a no.rmally low nut.rient envi.ronment enhancing the growth of algae and
pla.nkton which compete with corals for ava.ilable space and reduce water
t.ra.nspa.re.ncy. Terrige.nous sedime.nt i.nflux usually is accompanied by i.ncreased
nut.rients.
54
CONCLUSIONS
The results of this study indicated that the chai.n photo transect method proved to
be a fast. efficient and economical hard bottom community survey system, it also gives
a perma.nent record of reef sections without distu.rbi.ng the o.rga.nisms. Taggi.ng of
coral colonies gave excellent results in the identification of coral species. The use of
three ra.ndomly located chai.ns at each depth level allowed comparison of results
between study sites a.nd gave a good indication of what sample size is needed to survey a
given area. At least 15sq. meters of area should be covered on each depth leve! for total
coral cover determination. For the determination of coral species diversity, it is
recomended that at least two ra.ndomly located chains. each covering a mínimum of 10
sq. meters shoutd be surveyed at each depth leve! (Appendix 3).
The Shelf-Edge reef at Peñuelas and La Parguera reefs were free of excess
terrigenous sedimentation. Species richness a.nd coral cover values compared
favorably with other reefs of the Caribbea.n.
Reefs with abnormally high sediment inputs showed dec.reased coral species
diversity a.nd percent cover; but at the same time, some sediment resistant species
tolerate this adverse environment. The most common symptoms were partial or total
bu.ria! of coral colonies, bleachi.ng of colonies, a.nd colonization of coral surfaces by
sediment resistant coral species filamentous btue-g.reen algae a.nd sponges. Also,
deeper forereef corals dominated the community probably because light penetration is
diminished by tu.rbidity. Both species díversity and coral cover inc.reased with distan ce
f.rom the sediment source.
Bajo Tasmania.o.and Cayo Cardona we.re the two reef sites that showed the g.reater
damage from ch.ronic sedimentation. Bajo Tasmanian had low values of living coral
cover a.nd species diversity; living coral was not found below 18 m. Cayo Cardona was
the most severely aff ected of the study sites; coral g.rowth ended at 12m and only 11
living coral species were found, this was attributed to the eff ect that resuspension of
bottom sediments by ship traffic had on the coral fauna.
CayoRatones showed better coral cover and higher species diversity compared to
Bajo Tasma.nia.nand Cayo Cardona, but deeper parts of the reef were affected by
terrigenous sedimentation. Deeper reef fauna vas found to be living at shallowe.r
depths suggesting that the light levels were reduced. No living coral was found below
32mdepth.
55
Reef zonation and variations in coral diversity appear to be a response to natural
and man influenced stresses and energy inputs. Shallow parts of reefs receive
abundant sun1ight but also intense wave action: and surge, resu1ting in 1owspecies
diversity and moderate cover. Deeper parts of reefs with high sedímentation showed
reduced species diversity and cover. Light reduction is the principal problem that
excess sedímentation causes, but other problems, such as increased nutrient 1eve1scan
add to the detrimental conditions of a reef community. Increased nutrients cause an
íncrease on the plankton population whích can reduce even more light penetration,
and promote the growth of algae which compete wíth corals and other reef fauna for
substrate. The relationshíp between stress and diversity varíes with the magnitude and
duration of the stress. If the stress is small, diversity may in crease. However, diversity
decreases if stress is pro1onged or severe ( La.ng 1973.Thompson, 1979.Chesher 1%9b).
Sediment stress may reduce the vitality of a reef to .resist another problems such as
hurricanes, overfishing of selected reef fauna. Diadema antillarum wipeout. thermal
po11u~ion,etc.
Recovery depends on the type of stress. Although reef organísms are adapted to
natural levels of sedimentation, factors which increase sedimentation above normal
levels are very detrimental. When a reef community is destroyed, the eco1ogica1
conditions that follow cannot be expected to coincide with those which preceed the
initial development of the communíty. Thus it cannot be taken for granted that the
reef communíty will ever re place itself.
Even though corals do not account for the majority of the reef mass, it is well
established that when these die, their surfaces are rapidly co1onizedby filamentous
algae and other organisms which impedes the settlement of coral larvae and man y
fauna! elements of the reef community either die or emigrate (Chesher 1%9 b).
Reefs are a valuable natural resource which promote the economy of tropical
areas of the world. The survival of reefs depends on better understanding of the vital
processes that ta.ke place and the detection of stress signs on time. Studies dealing with
the physiological effects of stressed corals, long te.rm observation of stressed reefs. and
laboratory cont.rolled experiments with diverse species are crucial to the
understanding of their responses. Existing local water quality standards are for
temperate water invertebrates, in Puerto Rico, these should be modified to tropical
organisms which are less tolerant to environmental changes.
56
CITEDREFERENCES
Acevedo, R. a.nd C. Goe.naga. 1986. Coral Bleachi.ng after a Chronic Flooding i.n
Southwestern Puerto Rico. In press.
Adey. W. H. and R. Burke. 1976. Holocene Bioherms of Lesser Antilles-Geologic
Control Development. Smithsonian Research Report. pp. 67-79.
Alter. R. C. and R. E. Dodge. 1974. A.nimal-Sediment Relations in a Tropical Lagoon.
Discovery Bay, Jamaica. Journal of Marine Research. 32(2): 209-232.
Almy. C. C. Jr. and C. Carrión 1%3. Shallow Water Stony Corals of Puerto Rico.
Caribbean Journal ofScience, 3(2 and 3): 133-162.
Bak. R. P. 1977. Coral Reefs and their Zonation
in
Netherlands Antilles. In: S. H.
Frost, M. P. Weiss and J.B.Saunde.rs. eds. Reefs and Related CarbonatesEcology and Sedimentotogy, Studies in Geology no: 4, American Association of
Petroleum Geologists, Tulsa. pp. 3-16.
Bak, R. P. and J.H. B.Elgershuizen. 1976. Patterns of Oil-Sediment Rejection in
Corals. Curacao, Netherland Antilles. Journal of Marine Biology (37): 10)-113.
Barnes. D.J. 1973. Growth in Colonial Scleractinians.
23 (2): 280-297.
Bulletin of Marine Science
Beach, D.K. and J.V. Trumbull, 1981. Marine Geologic Map of the Puerto Rico
Insular Shelf. Isla Caja de Muertos Area. U. S. Geological Survey, Miscelaneous
Investigation Series, map I-1265.
Bohnsack, J. A. 1979. Photographic Quantitative Sampling of Hard-Bottom Benthic
Communities. Bulletin of Marine Science 29(2): 242-252.
Boulon. R. H., Jr. 1980. Patterns of Coral Community Structure and Species Diversity
on a Submerged Shelf-Edge off Southwestern Puerto Rico. M.S. Thesis,
University of Puerto Rico, Mayagoez, Puerto Rico 00708. pp. 61.
Chesher, R. H. 1969b. Acanthaster planci. Impact on Pacific Coral Reefs. Final
Report. Research Laboratory, Westinghouse Electric Company, Pittsburgh,
Pennsylvania. pp. 26.
Colín, P. L. 1978. Caribbean Reef I.nvertebrates and Plants. T. H.F. Publications, !ne.
L. T. D.,Neptune City, N. J. pp. 512.
Colón, E. F. 1971. Estuaries, Bays and Coastal Currents Around Puerto Rico.
Technical Reports No. 6, 7 and 8. Project A-031-PR. Water Resources Research
Institute, School of E.ngi.neering, University of Puerto Rico,Mayaguez,
Puerto Rico.
Connell, J.H. 1973. Population Ecology of Reef-Building Corals, in O.Jo.nes and R.
Endean, eds., Biology and Geology of coral reef, VoL 2: New York, Academic Press,
pp. 205-244.
57
Cortés N.J. and M. J.Risk. 1985. A Reef Under Siltation Stress: Cahuíta, Costa Rica.
Bulletin of Marine Science 36(2): 339-356.
Dahl, A. Lyon. 1981. Monitoring Coral Reefs for Urban Impact. BuUetin of Marine
Science 31<3): 544-551.
Dana, T. F. 1976. Reef-Cora1 Dispersion Patter.n.s and Environmental Variables on a
Caribbean Coral Reef. Bulletin of Marine Science, 260): 1-13.
Davies, P. J. 1977. Modern Reef Grovth..:Great Barrier Reef. P.roc. 3rd Inter.national
Coral Reef Symposium. 2: 325-330.
Dodge, R. E. and J.Thompson 1974. The Natural Radiochemical and Grovth Records in
Contemporary Hermatypic Corals from the AUantic and Caribbean. Earth and
Planetary Science Letter. 23: 313-322.
Dodge, R.E., A. Logan and A. A.ntonius. 1982. Quantitative Reef Assessment Studies in
Bermuda: A Comparison of Methods and Preliminary Results. Bulleti.n of Marine
Science. 32(3): 745-760.
D.rev, E. A. 1973. The Biology and Physiology of Alga1-I.n.vertebrate Symbioses III.
Journal ofExp1oratory Marine Biology andEcology. 13: 165-179.
Drev ..E. A. 19n. A Photog.raphic Survey Dov.n.the Seavard Reef-Front of Aldabra
Atoll. Atoll Research Bulletin. 193: 8-H.
Duarte-Bello, P. R. 1961. Corales de los Arrecifes Cubanos. Serie Educacional No. 2,
Acuario Nacional. Maria.nao, Cuba. pp. 85.
Du.n..ne,R. P. a.nd B. E. Brovn, 1979. Some Aspect of the Ecology of Reefs Sur.rounding
Anegada, British Virgin Islands. Smithonian Institution, Washington D. C.
Reseach Bu11etin No. 236, pp. 1-25.
Dustan, P. 1979. Dist.ribution of Zootha:nthellae and Photosynthetic Cloroplast Pigme:nts
of the Reef-Buildi:ng Coral Montastrea annularis Ellis and Solander in Relation to
Depth on a West Indian Coral Reef. Bulletin of Marine Science. 29(1 ): 79-95.
Folk, R. G. 1974. Pet.rology of Sedimentary Rocks. Hemphill Publishing Company,
Austin, Texas, pp. 182.
Glynn, P. W. 1973. Ecology of a Caribbean Coral Reef. The Porites Reef-Flat Biotope:
Part I. Meteo.rology and Hydrography. Bulletin of Marine Science.
20: 297-318.
--·
1973a.. Aspects of the Ecology of Coral Reefs in the Western Atlantic Region. In:
Biology and Geology of Co.ralReefs Z.. 271-324. Ed. by O.A. Jones and R. Endean.
New York: Academic Press. pp. 480.
--·
1976. Some Physical and Biologica.1Determinants of Corals Community Structure
in the Easte.rn Pasific. Reprinted f.rom Ecological Monographs. 46(4): 431-456.
58
Goenaga C. and G. Cintrón. 1979. Inventory of the Puerto Rican Coral Reefs. Puerto
Rico Department of Natural Resources. pp. 1-160.
Goreau, T. F. 1959. The Ecology of Jamaican Coral Reefs. I. Species Composition and
Zonation. Ecology. 40(1): 67-89.
Goreau, T. F. and N. l. Goreau. 1%3. The Ecology of Jamaican Coral Reefs.
II. Geomorphology, Zonatíon, and Sedimentary Phases. Bu11etinof Marine
Science. 23(2): 400-461.
--·
1959a. The Physio1ogy of Skeleton Formation in Corals. I. A Method for
Measuring the Rate of Calcíum Deposition by Corals Under Different Conditions.
Biological BuHetin. 116 (1): 59-75.
--·
1959 b. The Physiology of Skeleton Formation in Corals. II. Ca1ciumDeposition
by Hermatypic Corals Under Various Conditions in the Reefs. Bio1ogical Bulletin.
117(2): 239-250.
Goreau, T. F. and L. S. Land. 1974. Fore-reef Morphology and Depositiona1 Processes,
North Jamaica. In: Reefs in Time and Space, Socíety of Paleontologists and
Minearologists, Special Publication. No: 18, pp. 77-89.
Goreau, T. F. and J.W. We11s.1%7. The Sha11owWater Scleractiniansof Jamaica:
Revised List of Species and their Vertical Dist.ribution Range. Bu11etin of
Marine Science. 17: 442-453.
Grassle, F. J. 1973. Variety in Coral Reef Communities. In Jones and Endea.n, editors.
· Bíology and Geology of Coral Reefs II, Academic Press, New York. USA.
pp. 247-270
Hartman, W. D. 1973. Beneath Caribbean Reefs. Discovery, 9(1): 13-26.
Hubbard. J.A. E. B. 1973. Sedíment-Shifting Experiments: A Guide to Functional Behavior
in Colonial CoraJs. In: Animal Colonies, pp. 31-42.
James, N. P. and R. N. Ginsburg. 1979. Deep Barrier Reef and Fore-Reef. Chapter 3: The
Mo.rpho1ogy, Sediments and Organism of the Deep Bar.rier Reef and Fore-Reef.
pp. 25-64.
Jerlov, N. G. 1968. Optical Oceanography, In: Elsevier Ocean Series, No. 5, Elsevier
Publishing C9mpany, Nev York. pp. 194.
Johannes, R. E. 1970. Coral Reefs and Pollution. Dept. of Zoology, University of Georgia,
Athens, Georgia. pp. 13.
Kaye, C. A. 1959. Shoreline Features and Quaternary Shoreline Changes, Puerto Rico.
United States Department of the Interior, U. S. Geological Su.rvey. Professional
Paper 317-B: 49-140, figs. 6-63.
Kirby, M. J. 1969. Erosion by water on hillslopes. In: Water, Earth and Man.
R. J.Chodey (ed.), Methuen and Co.,L.T.D.,London. pp. 15-18.
59
Lang, J. 1971. Interspecific Aggression by Scleractinian Corals. Bulletin of Marine
Science, 21(4): 952-959.
---·
1973. Interspecific Aggression by Scleracti.nian Corals. Marine Science
Bulletin. 23(2): 260-279.
__
, 1974. Biological Zonation at the Base of aReef. American Scientist,
62(3): 272-281.
Las.k.er,H.R. 1980. Sedi.ment Rejection by Reef Corals: The Roles of Behavior and
Morphology in Montastrea cavernosa. Journal of Experiment of Marine Biology
a.nd Ecology. 47: 1158-1159.
Lelet.k.i.n,V. A. and V. l. Zvalí.ns.k.y. 1981. Photosynthesís of Coral Zooxanthe11aefrom
Different Depths. Proc. from the Fourth Internatíonal Coral Reef Symposium,
2: 33-37.
.
Levin, J. 1971. A Literature Review of the Effects of Sand Removal on a Coral Reef
Community. Natío.na! Science Foundation-Sea Grant No: GH-93. U.N. I. H. I. Sea
Grant TR-71-01.
Lewis, J. B. 1970. Spatial Distribution and Patterns of some Atlantic Reef Corals.
In: Nature. 227(5263): 1158-1159.
Link, R. F. and D. L. Wallace. 1952. Some Short Cuts to Allowances. In: Nonparametric
and Shortcut Statístics in the Social, Biological, and Medica! Sciences. Merle W.Tate
and Richard C.CleUand (eds.), Interstate Printers and Publishers, Inc. Danville,
Hlinois. pp. 119-122.
Loya, Y. 1971. Coral Reefs of Eliat (Gulf of Eliat, Red Sea), Symposium Zoological Society
ofLondon. No.28, pp.117-139.
--·
1972. Community Structure and Species Diversity of Hermatypic Corals atEliat,
Red Sea. Bulletín of Marine Science. 13(2): 100-123.
--·
1976. Effects of Water Turbidity and Sedimentation on the Community Structure
of PuertoRican Corals. Bulletin ofMarine Science. 26(4): 450-466.
Macintyre, I. G. 1968. Some Submerged Coral Reefs in the Caribbean. Transamerican
Fifth Caribbean Geological Conference BuUetin. No. 5: 49-54.
Marshal, S.M. and A. P. Orr. 1931. Sedi.mentatíon at Low Isles and its Relatíon to Coral
Growth. Scientífic Report Barrier Reef Expeditío.n. l(j): 94-133.
Marzalek, Donalds. 1981. Impact of Dredging on a Subtropical Reef Community,
Southeastflorida, U.S. A. Proceed by IV Internatíonal Coral Reef Symposíum
pp. 1-8.
Mayor, A. G. 1918. Growth Rate of Samoan Coral Reefs. Proceedi.ngs of the National
Academy ofSciences. 4: 390-393.
Millíman, J. D. 1973. Caribbea.n Coral Reefs. In: Jones O.A. and Endean, R. (eds.) Biology
and Geology of Coral Reefs, L pp. 1-50.
60
Morelock. J. N. Schneidermann a.nd W.R. Bryant. 1977. She1f Reefs. Southwestern
Puerto Rico. American Association of Petroleum Geologists. Studies in Geology.
4: 17-2:').
Morelock, J. K. Boulon a.nd G. Galler.1979. Sediment Stress a.nd Coral Reefs. In: Proc.
Symp. on Energy a.nd the Marine Environment in Guayanilla Bay. Center for
Energy and Environment Research. University of Puerto Rico, Mayaguez,
pp. 46-58.
Morelock, J.,M. Hernández a.nd J. Roberts. 1985. Playa Santa Isabel Oceanographic
Survey. Final Report Submited to: L. G. Suárez and Associates; Engineers,
Architects and Planners. U.npublished report. pp. 134.
Muscatine, L. et. al. 1979. Ammonium Uptake by Symbiotic a.nd Aposymbiotic Reef
Corals. Bu11etin of Marine Science. 29: 572..:575,
Muscatine, L. 1980. Productivity of Zoothanthellae.
pp. 381-402.
Primary Productivity in the Sea.
Ott, B. 1976. Quantitative Analysis of Community Pattern and Structure on Coral Reef
Bank in Barbados. West I.ndies, Ph.D. Thesis. McGill University, Ca.nada. pp 175.
Porter. J. W. 1972. Patterns ofSpecies Diversity in Caribbea.n Reef Corals. Ecology.
53( 4): 745-748.
--·
1974. Community St.ructure of Coral Reefs on Opposite Sides of the Isthmus of
Pa.nama. Science.186(11): 543-j4j.
Rogers, Caroline S. 1977. The Response of a Coral Reef to Sedimentation. Unive.rsity of
Florida, Bota.ny Dept., Ph. D.Thesis. pp. 195.
Roos, P. J. 1971. The Stony Corals of the Nethedands Antilles. Studies on the Fauna
of Curacao and Other Caribbea.n Islands, 371: 1-108.
Rosen, B. S. 1971. Principalfeatu.re ofReef Coral Ecology in Shallow Water
Environments of Mahé, Seychelles. Symposium Zoological Society of London.
8: 163-183.
Roy, K. J.and S. V. Smith. 1971. Sedimentation a.nd Coral Reef Development in Turbid
Water: fa.nning Lagoon. Pacific Science. 25: 234-248.
Saunders. C. E. 1973. Carbonate Sedimentation on the Inne.r Shelf, Isla Magueyes,
Puerto Rico. M.S. Thesis. University of Puerto Rico, Depa.rtment of Mari.ne
Science, Mayaguéz. pp. 77.
Scatterday, J.W. 1974. Reefs and Associated Coral Assembalges off Bonaire, Netherlands
Anti11es and thei.r Bea.ring on Pleistocene a.nd Recent Reef Models. Second
International Coral Reef Symposium. pp. 85-106.
Stoddart, D.R. 1%9. Ecology and Morphology of Recent Coral Reefs. Biology Revenue.
44: 433-485.
61
Taylor, D. L. 1969. On the Regulation and Maintenance of A1ga1Numbers on
Zooxanthe11ae-Coelenterate Symbiosis, with a Note on the Nutritional Relationships
of Anemonia sulcata. Marine Biological Associaton, United .Kingdon.
(49): 1057-1065.
Thompson, J. H., Jr. 1979. Effects of Drilling Mud on Seven Species of Reef-Building
Corals as Measured in Field and Laboratory. Final Report to the U. S. Geological
Survey. GrantNo.14-08-001-162.
Titlayanov, E. A. !981. Adaptation of Reef Building Corals to Low Light Intensity.
of the 4th. International Coral Reef Symposium. 2: 39-43.
Proc.
Trumbull, J. V. A. and L.E. Garrison. 1973. Geology of a System of Submarine Canyons
South of Puerto Rico. U. S. Geo1ogica1Survey Journal of Research. 1(3): 293-299.
U.nited States Coast Pilot 5. Atlantic Coast Gulf of Mexico, Puerto Rico and Virgin
Islands. Tenth Edition- July 1977. United States Department of Commerce,
National Oceanic and Atmospheric Administration. Natío.na! Ocean Survey,
Washington D. C. Wee.klyNotice to Mariners published by the Defense
Mappi.ng Agency, Hydrographic Center, No. 23, Ju.ne 4, 1977.
United States Naval Office Oceanog.raphic Atlas of the North AUantic Ocean, 1963.
Winds, State of Sea, SweUs and Waves. Publication No. 700, Section IV.
U. S. Naval Oceanog.raphic Office, Washington, D.C. pp. 228.
--·
1965. Tides and Currents. Publication No. 700, Section I. U. S. Naval
Oceanographic Office, Washington, D. C. pp. 76.
Weinberg, S. 1981. A Comparison of Coral Reef Survey Methods. Bijidragen tot de
Die.rkunde. 51(2): 199-218.
Weiss, M. P. and D. A. Goddard. 1976. Man's lmpact on Coastal Reefs-an Example from
Venezuela. Department of Geology, Northern Illinois University,
DeKalb, IUinoís 60115. pp. 111-124.
We11s,J. W. 1957. Corals. J. W.Hedgpeth, Editor. Unviersity of California, Scripps
Institute of Oceanography, La JoHa, California. Geological Society of America,
Memoír 67, 1: 1087-1104.
Yonge, C.M. 1930. Ecology and Physiology of Reef-Building Corals. In: Great Barrier
Reef Expedition 1928-29 Scientific Reports. H13): 373-391.
Zlatarsky, V. N. and N. Mart1nez. 1982. Le Scleractiniaries de Cuba. Editions de
L'Académie Bulgare des Sciences. Sofía. pp. 472.
62
63
PARGUERASHELF-EDGE
20 m PERCENT
COVER
BYSPECIES
SPECIES
M. ann.
M. cav.
Ag.ag.
P. ast.
P. fur.
Sid.s.
Mean.m.
Colpa.n.
Lepto.c.
Dip.s.
Dip.c.
Dip. l.
Stepha.m.
Mycet.l.
Mycet.f.
Mad.d.
Mad.m.
Mussaa.
ISO.r.
Seo.l.
lso.s.
Mill. a.
Mill c.
TOTAL
* LESSTHAN. 1 %
CHAIN1
in percent
19.3
1.7
9.4
3.4
*
1.7
0.8
0.5
*
o
CHAIN11
in percent
28
CHAIN111
in percent
24
MEANTRANSECT
VALUES
in percent
24
2.9
3
3
6
4
6
2
0.2
0.7
0.9
2
7
o
*
2
2.6
0.3
o
3
0.1
0.8
1
2
0.1
0.7
o
*
0.9
*
0.3
0.5
0.1
0.5
0.1
0.6
0.2
0.2
0.2
0.1
0.1
0.1
0.1
0.7
0.1
0.2
0.3
o
o
0.2
0.1
0.2
*
o
o
o
0.1
*
o
o
o
*
o
o
o
*
o
o
o
0.1
0.3
o
*
*
*
38.2%
48.Si
41.6%
43.2%
*
*
*
64
PARGUERA
SHELF-EDGE
25m PERCENT
COVER
BYSPECIES
SPECIES
M. ann.
M. cav.
Ag.ag.
Ag.1am.
P. ast.
Sid.s.
Mean.m.
Colpa.n.
Lepto.c.
Dip.c.
Dip.s.
Dip. l.
Stepha.m.
Mycet.l.
Mycet.f.
Mycet.a.
Mad.d.
Seo.c.
Isa.r.
Eus.f.
Mm.a.
TOTALS
* LESSTHAN. 1 %
CHAIN1
in percent
25
1.6
12.5
0.4
2
0.2
0.6
0.1
0.1
2.5
o
*
*
o
0.2
0.1
0.1
*
0.2
CHAIN11
in percent
30
2.5
16.6
o
3
0.2
0.4
o
o
o
*
0.3
0.2
0.2
0.3
o
0.1
*
o
o
o
0.1
45.7%
CHAIN111
in percent
24
2.5
16.4
o
4
0.7
1
o
0.4
o
o
0.8
*
0.5
0.5
0.1
o
o
o
MEANTRANSECT
VALUES
in percent
26
2.2
15.2
0.1
3
0.4
0.7
*
0.2
0.1
*
0.4
0.1
0.2
0.1
*
0.1
*
*
*
0.3
0.2
0.1
0.2
54.1%
51.2%
49%
65
PARGUERA
SHELF-EDGE
30m PERCENT
COVER
BYSPECIES
SPECIES
M. ann.
M.cav.
Ag.ag.
Ag.1am.
P.ast.
Sid.s.
Mean.m.
Lepto.c.
Dip.s.
Dip.c.
Dip. l.
Stepha.m.
Mad.d.
Mycet.1.
Mycet.f.
Mycet.a.
Dicho.s.
Eus.f.
Seo.c.
Míll.
a.
TOTALS
* LESSTHAN. 1 %
CHAIN1
in percent
16
2.5
13
1.4
0.4
0.3
0.4
o
0.1
*
0.3
0.4
0.7
0.1
CHAIN11
in percent
14
1.5
14
9.8
0.6
o
0.4
0.5
o
0.7
0.9
0.2
0.1
0.2
0.1
o
CHAIN111
in percent
14.5
4.1
15
2.2
4
0.2
0.2
0.1
1.4
o
o
o
0.1
*
0.1
o
o
0.1
0.5
*
*
o
o
o
o
o
o
o
37.7%
43.6%
41.9%
MEANTRANSECT
VALUES
in percent
14.7
2.7
14
4.4
2
0.2
0.3
0.6
0.4
0.2
0.3
0.1
0.2
0.2
0.3
*
*
0.1
*
*
40.7%
66
TURRUMOTE
S-E 15 mPERCENT
COVER
BYSPECIES
SPECIES
M.ann.
M.cav.
Ag.ag.
P.ast.
Sid.s.
Mean.m.
Colpo.n.
Dip.s.
Dip.c.
Dip.l.
Mycet.1.
Dicho.s.
A.cerv.
Mm.a.
Míll.s.
TOTALS
* LESSTHAN. 1 %
CHAIN1
in percent
9.3
3.1
1.6
1.5
0.5
0.3
1.5
*
CHAIN11
in percent
5.6
3
3
2
0.5
0.1
1.2
0.2
CHAIN111
in percent
4.5
1.3
1.5
0.5
2.4
0.7
0.2
0.1
0.3
0.4
0.2
o
o
0.2
0.2
1.5
o
o
o
0.2
0.2
0.2
0.3
16.4%
13.2%
0.1
o
18.8%
*
o
*
*
MEANTRANSECT
VALUES
in percent
6.5
2.4
2
1.3
1.1
0.4
1
0.1
0.1
0.7
0.1
*
*
*
*
15.7%
67
TURRUMOTE
S-E 20 m PERCENT
COVER
BYSPECIES
SPECIES
M. ann.
M. cav.
Ag.ag..
P. ast.
Sid.s.
Mean.m.
Colpo.n.
Dip.s.
Dip. l.
Stepha.m.
Mycet.l.
Mad.d.
A. cerv.
lso.r.
Mill. a.
Míll. s.
TOTALS
* LESSTHAN. 1 %
CHAIN1
in percent
7.5
9.4
4.6
2
1.6
0.9
o
o
o
O.1
o
o
o
o
o
o
26.1%
CHAIN11
in percent
4.1
4
2.7
1.6
1.3
0.6
1.3
CHAIN111
in percent
3
11.5
3.2
0.1
0.2
o
o
o
o
0.5
1.5
0.1
0.2
0.4
*
MEANTRANSECT
VALUES
in percent
4.9
8
3.5
1.5
1
0.6
0.4
0.1
0.5
*
*
o
o
o.1
0.8
0.2
*
o
*
*
*
*
*
*
16.2%
21.9%
20.8%
o
68
TURRUMOTE
5 m PERCENT
COVER
BYSPECIES
SPECIES
CHAIN1
in percent
M.ann.
P. ast.
Sid.s
Dip.s.
Dip.c.
Stepha.m.
A. pal.
A. cerv.
Mill. a.
o
TOTAL
*LESSTHAN. 1%
0.7
0.2
1.5
*
*
1.5
0.7
CHAIN11
in percent
0.7
4.3
0.4
0.5
o
o
o
CHAIN111
in percent
0.7
1.4
0.1
0.5
MEANTRANSECT
VALUES
in percent
0.5
o
o
*
*
2.2
0.3
0.8
5.2
2
*
0.6
*
1.1
0.4
4.6%
7.4%
8.9~
0.4
6.8%
69
TURRUMOTE
1O m PERCENT
COVER
BYSPECIES
SPECIES
M. ann.
M. cav.
Ag.ag.
P. ast.
P. por.
Sid.s.
Sid.r.
Mean.m.
Colpo.n.
Dip. s.
Stepha.
Mad.d.
Mycet.1am.
Mycet.al.
Mycet.d.
A. cerv.
Eusm11ia.
f.
Seo. 1.
Mill. a.
Mill.sq.
TOTAL
*LESSTHAN. 1%
CHAIN1
in percent
2.9
1.8
1.2
0.2
1.7
1.4
CHAIN11
in percent
15.5
3.9
0.8
0.3
o
*
CHAIN111
in percent
11.3
0.9
4.5
0.6
0.3
3.4
MEANTRANSECT
VALUES
in percent
9.9
2.2
2. 1
0.4
0.7
1.6
o
o
0.1
0.2
o
o
2.7
o
*
3.8
2.2
o
o
0.2
o
o
o
0.5
0.4
0.3
o
o
o
0.2
o.1
0.1
0.2
o
5.5
*
o
o
*
o
*
*
*
*
0.3
*
*
1.8
*
*
o
0.2
0.1
0.2
0.4
*
*
0.3
22.1%
25.6%
21.7%
o
18%
o
o
*
70
ENRIQUE
5 m PERCENT
COVER
BYSPECIES
SPECIES
M.ann.
M. Ca>/.
Ag.ag.
P. ast.
P. por.
P. fur.
Sid.s.
Colpo.b.
A. pal.
A.cerv.
Mycet.1.
Dendro.
c.
Mill. a.
Mili. c.
TOTALS
* LESSTHAN. 1%
CHAIN1
in percent
13
CHAINII
in percent
11
o
o
0.9
1
0.8
0.2
0.4
o
o
o
MEANTRANSECT
VALUES
in percent
18
*
*
o
o
o
o
0.7
0.4
0.7
0.2
0.6
1.4
1.6
0.1
0.2
0.6
0.3
0.8
0.5
o
*
*
21.7%
34.3%
25%
o
0.7
0.8
0.2
0.4
2.8
4.7
o
0.5
1.7
0.4
o
18.1%
CHAIN111
in percent
29
0.1
0.4
0.2
2
0.3
0.9
0.6
o
71
ENRIQUE
1Om PERCENT
COVER
BYSPECIES
SPECIES
M. ann.
M.cav.
Ag.ag.
P. ast.
P. fur.
Sid.s.
Mean.m.
Colpo.n.
Colpo.b.
Lepto.c.
Stepha.m.
A. eerv.
Mycet.l.
Mad.d.
Seo.e.
Seo.l.
Mill. a.
TOTALS
* LESSTHAN. 1%
CHAIN1
in percent
10.6
*
5.5
0.4
0.5
0.9
o
2.7
o
o
CHAIN11
in percent
1.1
1.2
7.3
1.6
o
2.1
0.2
1.8
o
CHAIN111
in pereent
0.4
2.5
15.8
o
0.5
1.1
o
0.6
0.6
0.1
o
0.1
0.3
0.1
0.3
0.1
0.3
o
o
*
*
o
o
*
14.1
o
o
*
35%
16.1%
o
o
o
0.5
22.2%
MEANTRANSECT
VALUES
in percent
3.9
1.3
9.5
0.7
0.1
1.4
*
1.8
0.2
0.1
0.1
4.6
0.1
0.1
*
*
0.2
24.1%
72
BAJOTASMANIAN
1Om PERCENT
COVER
BYSPECIES
SPECIES
CHAIN1
in percent
o
M.ann.
M.CfN.
Ag.ag.
Por.ast.
Síd.s.
Mean.m.
Colpa.n.
Dip.s.
Mad.d.
A.cerv.
Eusmilia.f.
Dendro.c.
Mill. a.
0.1
TOTALS
4.5%
* LESSTHAN. 1%
1.7
o
o
1.4
1.3
o
o
o
o
o
o
CHAIN11
in percent
*
CHAIN111
in percent
4.2
3.5
*
0.2
0.2
0.2
*
o
*
*
*
0.5
*
*
o.s
*
*
*
o
o
o
o
0.2
0.3
o
o
o
TRANSECT
MEAN
VALUES
in percent
I.S
2
*
0.1
*
0.7
1.6
0.2
0.4
5.3%
7.2%
5.5%
0.5
73
BAJO
TASMANIAN
t 5 m PERCENT
COVER
BYSPECIES
SPECIES
M.ann.
M.CfN.
Ag.ag.
Ag.1am.
P.ast.
Sid.s.
Mean.m.
Lepto.c.
Stepha.m.
Mycet.l.
Mad.d.
Mm.a.
TOTALS
* LESSTHAN. 1%
CHAIN1
in percent
CHAIN11
in percent
CHAIN111
in percent
0.3
2. t
0.3
0.4
0.3
o
1.5
1.8
o
o
o
0.2
o
0.3
0.8
o
o
4.4%
o
0.4
o
o
o.t
TRANSECT
MEAN
VALUES
in percent
0.3
2
0.3
o.t
*
*
*
*
0.2
o.t
0.2
0.2
0.2
o
o
o
0.1
*
*
*
*
2.5%
2.6%
3.1%
o
o
*
0.2
0.2
74
CARDONA
5 m PERCENT
COVER
BYSPECIES
SPECIES
CHAIN1
in percent
CHAIN11
in percent
CHAIN111
in percent
TRANSECT
MEAN
VALUES
in percent
Dicho.s.
Sid.s.
Dip._s.
Mm.a
0.3
o
*
0.1
*-
o
0.3
*
o
0.1-
o
*
TOTAL
.3i
·.1i
ti
.4i
*
o
0.7
0.3
*
LESSTHAN. 1:g:_
CARDONA
1OmPERCENT
COVER
BYSPECIES
SPECIES
M.ann.
M.~.
Ag.~.
P. ast.
Sfd.s.
Mean.m.
Dip;s.
Dicho.~
Moo.d.
CHAIN1
in percent
0.4
2
o
CHAIN11
fn percent
o
CHAIN111 MEANTRANSECT
VALUES
fn percent
1npercent
o
0.1
2.7
2.7
2.5
*
*
*
o
0.1
0.1
0.2
0.2.
0.1
1.4
*
0.3
....
º"
o
*
o
o
0.2
o
o
0.3
*
*
*
*
0.2
o
o
0.1
TOTAL
3.4i
4.6i
3.2i
* LESSTHAN. 1i
0.6
0.3
Stepha.m.
Mfll. a.
Oculinad.
o
*
0.1
o
*
*
*
*
3.6i
75
RATONES
S m PERCENT
COVER
BYSPECIES
SPECIES
M.ann.
CHAIN1
CHAIN11
CHAIN111
MEANTRANSECT
VALUES
in percenl
in percent
In percenl
3.9
in percent
1.2
\.6
. M. c::v.
o
.A.g.~
0.4
l.1
P.~L
o
1.5
C.5
?_,-;
OA
,_ ....
-
:~
0.2
o
o
o
o
L1
0.3
0.5
0..2
2.1
0.2
o
o
0.1
TOTA!..
2.3
0.1
0.1
6.1%
5%
6.2%
*LESSTh.<\N
.\ %
RATONES
10 m PERCENT
COVER
BYSPEC!ES
SPEC!ES
CHAIN1
CHAIN11
in percent
in perc:2nt
M. ann.
l."':
1.1
M. C?.V.
7.2
A"""
"":"~
P. ~t.
1.4
3.2
0.7
('\ e •
1.3
S!d..~
o..:;
o
tj~
-·"'
.üL
~.1~rt
L:ptn...c..
Dip.s.
Dic. c.
Dip. l.
Stepham.
Mad.d.
+
*
o?_
o
*
*
o
CPAIN111
in percenl
2.3
1.7
MEANTRANSECT
YALUES
in percent
1.6
4.1
2.4
1.5
1
o.e
0.5
0.7
o.1
o
0.7
0.2
V
*
o
o
*
..,
•J.!
C.3
"
f"\
o
o
o
r; ...,.
~-
*
0.6
0.2
o
o
o
.;,,
"'
Dicho.s.
Mill. a.
0.1
o
o
o
*
*
*
*
TOTALS
11.5%
8.4%
9%
9.5%
; LESSTfJAN. t ~
76
RATONES
15 mPERCENT
COVER
BYSPECIES
SPECIES
M.ann.
M.cav.
Ag.ag.
Ag.1am.
P.ast.
Síd.s.
Mean.m.
M~.d.
Mycet.1am.
Stepha.m.
lso.r.
Mm.a.
M111.sq.
TOTAL
* LESSTAHN. 1i
CHAIN1
CHAIN11
CHAIN111
in percent
in percent
in percent
4.4
2.9
2.3
1.5
4
o
0.6
0.2
0.2
0.2
1.3
3.7
0.5.
1.1
0.1
o
*
*
o
o
o
o
o
o
o
o
10.1i
12.3i
2.3
3.6
3.3
0.9
0.3
1.4
0.5
0.9
o
*
*
*
TRANSECT
MEAN
VALUES
in percent
3.3
3.4
2.9
0.5
0.7
0.6
0.3
0.8
*
*
*
*
*t
*
13.2i
12.si
77
RATONES
20 m PERCENT
COVER
BYSPECIES
SPECIES
M.ann.
M. aw.
Ag.ag.
Ag.1am.
P. ast.
Sid.s
Mean.m.
Lepto.c.
Mad.d.
ISO.s.
Mycet.1am.
Stepha.m.
Eusmrna.
f.
TOTAL
*LESSTAHN.1 i
CHAINI
in percent
0.2
1.6
3.7
1.2
0.2
0.2
*
CHAIN11
in percent
1.6
1.3
3.2
o
o
o
0.7
0.1
0.2
0.2
0.1
0.1
o
o
*
o
o
o
7.2i
7.4i
*
CHAIN111 TRANSECT
MEAN
VALUES
in percent
in percent
o
0.5
0.5
t. 1
2.1
3
0.7
1.3
o
*
0.4
0.4
0.1
0.1
*
0.1
*
0.1
0.1
0.1
o
*
0.1
*
*
*
4i
6.7i
78
PATONES
25 m PERCENT
COVER
BYSPECIES
SPECIES
Cl-'AIN
1
in percent
NJ.ag.
NJ.lam.
P. ast
o
4
0.4·
CHAIN11
in per:ent
o
s
*
o
o
Sid.s.
Mad.d.
Stepha.
m.
Mean.m.
0.5
o
o
TOTAL
4.9%
si
o
o
o
CHAIN111 MEANTRANSECT
VALUES
in percent
in percsnt
1.2
0.4
2.6
3.9
o
0.1
O.T
0.2.
O.J
o.l
0.2
*
*
*
4.4%
4.8%
*LESSTHAN. 1%
PATONES
30 m PERCENT
COVER
BYSPECIES
SPECIES
Ag.1am.
Mad.d.
TOTAL
CHAIN1
in percent
0.04
0.03
.07%
CHAIN11
in percent
0.06
o.os
.11%
CHAIN111 TPANSECT
MEAN
VALUES
in percent
in percent
o
0.04
O.l
0.08
.1%
.12%
79
PEl'1UELAS
15 m PERCENT
COVER
BYSPECIES
SPECIES
M.ann.
M.C'cN.
Ag.ag.
Ag.1am.
P.ast.
Síd.s.
Mean.m.
Colpo.n.
Lepto.c.
Díp.s.
A.cerv.
Mad.d.
Mad.m.
Stepha.m.
lso.r.
Seo.l.
Eus.f.
Míll. a.
TOTAL
*LESSTHAN. 1%
CHAIN1
in percent
7
2.4
2.3
o
2
0.2
0.1
4.2
*
*
CHAIN11
in percent
22.5
1.5
4.5
0.3
1
0.4
0.4
0.1
*
*
CHAIN111 MEANTRANSECT
YALUES
in percent
in percent
15.5
16
2.3
2.1
3.5
3.4
o
0.1
1.9
1.6
0.7
2.1
0.3
0.3
2.7
2.3
o
o
0.6
0.3
0.1
0.2
0.3
0.2
o
o
0.1
o
o
0.3
1.6
0.1
0.2
0.1
*
o
o
*
*
0.1
*
*
*
*
o
*
o
o
0.1
*
0.2
0.1
18.9i
31.1 %
29.6%
28.7%
80
PHfUELAS
20 m PERCENT
COVER
BYSPECIES
SPECIES
M. ann.
M.C'fN.
Ag.ag.
Ag.1am.
P.ast.
Sid.s.
Mean.m.
Colpo.n.
Lepto.c.
Dip.s.
Dip.c.
Stepha.m.
Mad.d.
Mycet.l.
Scol.l.
Dicho.s.
Mill. a.
TOTAL
* LESSTHAN. 1%
CHAIN1
in percent
5.5
2.2
10.5
0.7
0.9
1.3
0.7
o
*
0.4
o
o
CHAIN11
in percent
11.3
2.7
4.9
0.3
1.l
0.8
1.5
0.2
0.4
0.2
*
CHAIN111
in percent
14.1
1.5
3
o
2.1
0.5
0.3
0.8
0.4
o
o
MEANTRANSECT
VALUES
in percent
10.7
2.1
6.2
0.4
1.4
0.9
0.9
0.3
0.3
0.2
*
0.6
0.5
0.2
o
o
0.1
0.1
0.3
*
o
*
o
0.4
*
0.1
0.2
*
*
*
*
22.8%
24.5%
23.3%
24.1%
0.2
0.1
0.1
81
PEijUELAS
25 m PERCENT
COVER
BYSPECIES
SPECIES
M.ann.
M.CfN.
Ag.ag.
Ag.1am.
P.ast.
Sid.s.
S1d.r.
Mean.m.
Lepto.
Dip.s.
Stepha.m.
Mad.d.
Mycet.l.
Dicho.s.
Sol.b.
Seo!.l.
lso.r.
Eus.f.
Mil!. a.
TOTAL
* LESSTHAN. 1%
CHAIN1
in percent
1.8
1
9.8
0.5
0.3
0.7
o
1.5
0.5
0.7
0.2
0.1
2
*
CHAIN11
in percent
2.3
1.4
9.6
0.5
0.2
0.2
*
0.1
0.2
*
0.6
0.3
0.2
o
o
CHAIN111 MEANTRANSECT
VALUES
in percent
in percent
4
2.7
2.7
1.7
5. 1
8.2
o
0.4
1.4
0.6.
0.1
0.5
o
*
1.1
0.2
0.1
1.8
0.2
0.5
0.4
0.9
0.3
0.3
0.9
0.2
0.8
0.1
*
*
*
*
o
o
0.4
*
o
o
o
o
o
0.2
*
0.2
0.1
17.8%
17.7%
0.1
19.4%
*
16%
82
PEFlUELAS
30 m PERCENT
COVER
BYSPECIES
SPECIES
M. ann.
M. cav.
Ag.ag.
Ag.1am.
Sid.s.
Mean.m.
Mad.d.
Lepto.c.
Dicho.s.
Seo.l.
Stepha.m.
Mm.a.
CHAIN1
in percent
0.1
0.4
3.9
2.1
0.1
TOTAL
* LESSTHAN. l %
*
CHAIN11
in percent
o
0.4
3.7
4.3
o
o
0.5
0.1
0.3
o
o
*
*
o
o
o
CHAIN111
in percent
0.1
0.7
2.4
4.9
0.2
0.3
*
MEANTRANSECT
VALUES
in percent
0.1
0.5
3.4
3.8
0.1
0.1
0.1
o
o
o
*
*
*
*
o
0.1
*
*·
*
7.2%
8.8%
8.6%
8.1%
83
84
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25m
30m
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6
FREQUENCY- DISTRIBUTION CURVES.
7
8
89
90
Parguera
25
I
20
Cum. # of
Cor a 1 Species
15•
Shelf-Edge 20 m
_.
•
1
10
5
o
2
Chain u
3
Parguer a She lf-Edge 25 m
15
Cum. u of
Coral Species
10
5
2
Chain
3
11
91
P arguer a She lf-Edge 30 m
20
18
t
•
•
16•
14
12
Cum. u of
Coral Species
10
8
6
4
2
o
2
Chain u
3
92
Turrumote
¡
14
12
•
•
10
Cum. 0 of
Coral Species
S-E 15 m
8
6
4
2
o
1
2
Chain
Turrumote
°
3
S-E 20 m
14
12
•
10
Cum. 0 of
Cor a 1 Species
8
6
•
4
2
o
1
.2
Chain
°
3
93
Turrumote
5 m
6
5
Cum. # of
Cor .al Species
4
3
2
2
Chain
Turrumote
'ª
16
j
#
1O m
.,.,.-,,.,,.
•
14
12
Cum. 0 of
Coral Species
10
•
8
6
4
2
o
1
2
Chain
°
3
94
Enrique 5 m
•
12
10
8
Cum. u of
Cor a 1 Species
6
•
4
2
o
2
Chain
3
#
Enrique 1O m
16
14
Cum # of
Cor a 1 Species
t
•
::t
8
6
4
2
o
2
Chain
3
#
95
Bajo Tasmanian 1O m
12
10
8
Cum. u of
Cor a 1 Species
6
4
.,
2
o
2
3
Chain u
BaJo Tasmaman 15 m
·:¡---------·~~
7 .,_--,---
6
Cum u of
Coral Species
l
5
4
3
2
2
Chain
'*
3
96
Cardona 5 m
30f
2.5
•
2.0 •
Cum. **of
Cor a 1 Species
1.5
1.0
0.5
O.O
1
2
Chain
3
*'
Cardona 10 m
·:¡
7•
6
Cum.
#
of
Cor a 1 Species
5
4
3
2
o
2
Chain
3
#
97
Ratones 5 m
:l1•-
_,.,...
-·
-----
6
Cum. • of
Coral Species
5
4
3
2
o
1
2
Chain •
3
Ratones 10 m
14
12
10
Cum. • of
Cor a 1 Species
¡
•
•
8
6
4
2
o
1
2
Chain •
3
98
Ratones 15 m
f
12
10
•
a•
Cum. • of
Cor a 1 Species
6
4
2
o
1
2
3
Chain •
Ratones 20 m
12
10
8
Cum. • of
Cor a 1 Species
¡
-
_.
•
6
4
2
o
1
._______________________________________
2
3
Chain •
--
99
Ratones 25 m
•
7
6
5
Cum. **of
Cor-al Species
4
3 •-----------
4.-
2
3
2
Chéiin
'*
.Ratones 30 m
2.0 •----------•----------·
1.5
Cum.
**of
Cor-a 1 Species
1.0
0.5
2
Chain
3
'*
100
Peñue las 15 m
16
14
12
¡
•
•
10
0
of
Cum.
Cor a 1 Species
8
6
4
2
o
2
Chain
3
#
Peñue las 20 m
16
14
12
=
Cum. of
Cor a 1 Species
10
•
f
•
8
6
4
2
o
2
Chain
3·
#
101
Peñue las 25 m
18
16
14
¡
•
•
12
Cum. # of
Cor a J Species
10
8
6
4
2
o
1
2
Chain
3
#
Peñue las 30 m
,2
I
•
101
s•
Cum. # of
Coral Species
6
4
2
o
1
2
Chain
3
#