oculina coral banks of florida: conservation and management of a

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OCULINA CORAL BANKS OF FLORIDA: CONSERVATION
AND MANAGEMENT OF A DEEP-WATER RESERVE
John K. Reed
Division of Biomedical Marine Research, Harbor Branch Oceanographic Institution, 5600 US 1 N, Fort Pierce, FL 34946;
[email protected]
INTRODUCTION
In 1975, during photographic surveys of the continental shelf using the Johnson-Sea-Link Research Submersible,
scientists from Harbor Branch Oceanographic Institution discovered high relief pinnaCles at depths of 70-100
m that were living coral reefs composed entirely of the
ivory tree coral Oculina varicosa. Various research ensued
including studies on coral growth rates, community
structure of associated invertebrates and fishes, effects
of upwelling, bioerosion, sediments, geology, and taxonomic studies of fish, decapods, mollusks, echinoderms,
sipunculids, pycnogonids, and amphipods. During the
1970s these deep-water reefs were teeming with large
populations of grouper, snapper, and amberjack. Fishing pressure from both commercial and recreational
fishermen was intense, and by the early 1990s the fish
populations and the coral had been severely impacted.
Legislation in 2000 designated a 300 nmF (1029 km 2 )
Oculina Coral Bank Habitat Area of Particular Concern
(HAPe) which prohibits use of anchors, bottom trawls,
bottom longlines, dredges, fish traps and pots (Figure 1).
BANK DESCRIPTION
Coral Morphology and Distribution
A unique deep-water Oculina coral reef stretches over 90
nmi (167 km) along the shelf edge from Fort Pierce to
Figure 1. 300 nmil Oculina Bank Habitat Area of Particular Concern (HAPC) off the east coast of Florida that is protected from
bottom longlines, trawling, dredging, pots, and anchoring.
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Daytona, Florida, at depths of 70-100 m, and ranges
from 32 to 68 km offshore (Avent et al., 1977; Reed,
1980; Thompson and Gilliland, 1980; Virden et al.,
1996). A single species of branching scleractinian coral,
Oculina varicosa Lesueur, 1820, the ivory tree coral,
grows on these reefs. The reef system consists of over one
hundred individual coral pinnacles, mounds, and ridges
that are high relief structures, ranging from 3 to 35m
in height and 100-300 m in width (Figure 2; Reed,
1980). Each pinnacle is actually a veneer of living coral
overlying a mound of sand and mud sediment, coral debris, and oolitic limestone base formed during the
Holocene transgression. The reefs are termed coral banks
because they are below the effective wave base and the
coral lacks zooxanthellae, the algal symbiont of shallowwater reef corals.
Benthic Communities
The biodiversity of the Oculina banks is similar to shallow tropical reefs. Quantitative studies found over
20,000 individual invertebrates living among and within
the branches of 42 small Oculina colonies, yielding 230
species of mollusks, 50 species of decapods, 47 species
of amphipods, 21 species of echinoderms, 15 species of
pycnogonids, 23 families of polychaetes, and numerous
other taxa, e.g., sipunculids, nemertines, isopods, tanaids,
ostracods, and copepods (Miller and Pawson, 1979;
Figure 2. Massive colonies of Oculina varicosa growing on the
slopes of a coral bank at 80 m.
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Reed et al., 1982; Reed and Hoskin, 1987; Reed and
Mikkelsen, 1987; Child, 1998).
Fish Communities
The invertebrate community helps support the dense and
diverse populations of fishes (>70 species). The Oculina
banks form impressive breeding grounds for commercially important populations of gag and scamp grouper;
nursery grounds for juvenile snowy grouper; and feeding grounds for these and other fish including black sea
bass, red grouper, speckled hind, warsaw grouper, jew
fish, almaco jack, greater amberjack, red porgy, red
snapper, gray snapper, little tunny, giant sunfish, manta
ray, tiger shark, hammerhead shark, and scalloped hammerhead (Reed and Gilmore, 1981; Reed, 1985; Gilmore
and Jones, 1992).
Coral Growth
Long-term growth experiments were conducted on the
deep-water Oculina coral banks (80-m depth) using
lockout diving from the ]ohnson-Sea-Link research submersibles. The growth rate of the deep-water Oculina
coral at 80 m averaged 16.1 mm yr' and was significantly
greater compared to the growth at 6 m (11.3 mm yr';
Reed, 1981). Growth rate was significantly positively correlated with water temperature at both sites, but
paradoxically the coral growth was faster in deep water
where it lacks zooxanthellae.
Human Impacts
Extensive areas of 'dead coral rubble are present throughout the Oculina bank system, but the exact cause(s) is
yet unknown. Impact has certainly been the result of
commercial and sport fishing. The benthic commercial
fisheries in this region use dredges for scallop; bottom
trawls for royal red shrimp and rock shrimp; and bottom longlines for grouper, snapper, and shark. The
banks are at the edge of the Gulf Stream, so bottom hook
and line fishing requires heavy weights which damage
the coral. Early in the 1970s the Oculina banks were
teaming with large populations of snapper and grouper.
By the late 1980s both commercial and recreational
fisheries had taken a toll on the fish populations, especially grouper and snapper, and the coral had been
impacted. Other hypotheses may account for some of
the damaged reef areas. Natural episodic coral die-off,
such as occurs with the shallow-water Acropora species,
may be an unknown factor on the deep-water coral
banks. Do fungi and other pathogens that attack shallow-water reef corals also affect deep-water ahermatypic
coral species? These questions remain unanswered.
PROTECTION AND MANAGEMENT
Federal and State Regulations
In the United States, corals and coral reefs are protected
and regulated by various federal and state legislation. The
State of Florida has jurisdictional limit of 3 miles in the
Atlantic Ocean and it bans the taking, destroying or selling of scleractinian corals. Beyond the 3-mile limit, the
AAUS 20th Sl/mposium ProceedingS 2000
federal waters are regulated by the Minerals Management
Service through the Outer Continental Shelf Lands Act
of 1978. This requires permits for damaging or injuring
corals by mineral, oil, or gas leasors. Some reef areas that
are National Marine Sanctuaries are protected by the
Fishery Conservation and Management Act.
Fisheries in the region of the Oculina banks are managed through the South Atlantic Fishery Management
Council's Fishery Management Plans (FMPs), as approved and implemented by the National Marine
Fisheries Service (NMFS). The FMPs are implemented
under the authority of the Magnuson-Stevens Fishery
Conservation and Management Act by regulations 50
CFR part 622. The Magnuson-Stevens Act, as amended
by the Sustainable Fisheries Act, requires the Fishery
Management Councils to describe and identify essential fish habitats (EFH) in all FMPs, including
identification of adverse impacts from both fishing and
non-fishing activities. Also created are several EFHHAPCs which are habitat areas of particular concern that
are not only important to fish species, but are also considered critical for fish reproduction and growth to
maturity.
Oculina Bank RAPC
The deep-water Oculina banks were nominated in 1980
by the author as a Habitat Area of Particular Concern
(HAPC) within the Fishery Management Plan for Coral
and Coral Reefs. In 1984, a 92 nmF (315 km2 ) portion
was designated the Oculina Bank HAPC (Federal Register 49 FR 29607, July 1984). In 1994, the Fishery
Management Council banned fishing for grouper and
snapper within the Oculina Bank HAPC in order to
evaluate the benefits of marine reserves. This ban on
grouper and snapper fishing will be reevaluated in 2004.
Legislation was adopted in 2000 (Federal Register 50 CFR
part 622, vol. 65, no. 115, June 2000) to expand the
Oculina"Bank HAPC to encompass approximately 300
nmF (1029 km 2 ) of shelf-edge habitat. The following restrictions apply to the expanded Oculina Bank HAPC:
no person may (i) use a bottom longline, bottom trawl,
dredge, pot, or trap; (ii) if aboard a fishing vessel, anchor, use an anchor and chain, or use a grapple and
chain; (iii) fish for rock shrimp or possess rock shrimp
in or from the area.
Enforcement
Stringent surveillance and enforcement is not likely to
be 100% for this deep-water reserve or any that is so remote from coastal areas. However, random surveillance
by various means such as spotter planes along with the
occasional helicopter and enforcement vessel may impact the major offenders. Required use of vessel
identification systems is also gaining acceptance. Education regarding the importance and delicate nature of
these rich resources is important for both the commercial and recreational fishermen. This will lead to
better self-regulation and surveillance by the fishing
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community itself. Although large scale commercial fisheries' impacts could be devastating, the small repetitive
impacts from the uninformed recreational fishermen
may also have long-term consequences to the health of
the reefs. It is also important to educate the enforcement
personnel so they have a better understanding what
they are protecting and why. By bringing knowledge of
these deep-water coral banks to the public and the fishing community though videos, photos, and education
will we gain their acceptance for the need of protection
for these unseen resources.
ACKNOWLEDGMENTS
Numerous individuals have contributed to this research
over many years. I especially thank Dr. Robert Avent who
initiated these studies and Dr. Charles 'Skip' Hoskin who
provided years of enthusiastic collaboration and leadership. This is Contribution No. 1378 from Harbor
Branch Oceanographic Institution.
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