bay ecology guide - Environmental Volunteers

BAY ECOLOGYGUIDE
great blue heron
ENVIRONMENTAL VOTUNTEERS@
ggZLEastBayshoreRoad, Palo Alto, CA 94303
(650)961-0545/[email protected]
-,
_
2048 C orporate C t
S an Jose, C A 9513i
w w w .magel l anw orl d.com
Volunteersgratefully acknowledges
Environmental
MagellanWest,LLC for printing this guide.
EnvironmentalVolunteers- Bay EcologyEV Training Guide
EV M i s s i on ..............
EnvironmentalLearningGoals
Bay EcologyGuide Objective
I n t r o d u c ti o n............
Bay..........
A GeologicalHistory of SanFrancisco
How the BayWas Formed.............
W a te rC o n d i ti o n s...............
SomeBasicEcologicalConcepts.
BayEcosystems...............
An Overviewof SanFrancisco
Introduced Species
About Birds
Open Water Estuary Ecosystem,Flora and Fauna
Mud Flat Ecosystem,Flora and Fauna
Salt Marsh Ecosystem,Flora and Fauna
Salt Pond Ecosystem,Flora and Fauna
Upland Ecosystem,Flora and Fauna
Bay..........
F{umanInteractionwith SanFrancisco
Human History
Effectof Human Impact
Striving to Savethe Bay
Destructionof Wildlife
Declinein Water Quality
Climatic Changes
RecreationLoss
EarthquakeHazard
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.....page
1
.page1
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1
.......pages2 - 3
pages3 - 4
pages4 - 5
pages5 - 7
pages7 - 8
pages8 - 11
pageL1
pages12- 73
...............pages
13- 17
pages13 -14
pagesL5- 16
page 17
: i::!li3i;1"
H-;:'3J1':il:",LT:'l'i;;;;.;";;il,;s
Beforethe ClassroomVisit
Doing the Introduction
SuggestedLearning Stations
Closing Presentation
Glossary..
Reading
Suggested
SanFranciscoBayResources
Bibliography......,.....
With SpecialThmtksto:
L99LEducationCommittee:
BarbaraCallison,chair
Buffy Caulkins
JaneHall
Nancy Rubin
Pages20'22
..............page23
...............pages23
-25
page25
Editor
Karen Meisenheimer
Copy Editor
jan Whitmer
Illustrations Courtesy:SanFranciscoBay National Wildlife Refuge,SnltMarshManunl
EVS MISSION
The Environmental Volunteers mission is to promote understanding of, and responsibility for, the
environmentthrough hands-onscienceeducation.
The Environmental Volunteersworks to achievethis mission by:
. encouragingcommunity awarenessof the interrelationshipsof humans with the environment,
. giving those reachedthe tools to be able to make informed decisionsabout the environment,
. fostering in the community an attitude of stewardshipand responsibility for the environment.
ENVIRONMENTAL
LEARNING GOALS
Environmental education leads studentsto discoverthat all living things, including people, are
interdependent.We must cooperatein using and reusingour limited resources,which give and sustain
all life on earth.
The following five-fingered,"hands-on"approachto environmentaleducationis the basisof the EVs
teachinggoals.Finger one is sensoryawarenessfor the diversity of the world around us; finger two
representsthe values we hold, as well as thosethat needto be developed;the third finger is an
awarenessof historical changesand a senseof continuity;finger four symbolizesthe interdependency
of all things in our world; and finger five remindsus of our needto fostera senseof stewardship
toward all life.
The EVsbelievethat the bestmethod for leaming is through hands-onand other participatorymethods
of teaching.EV materials are organized to enhancethis style of teaching.Our leaming materials foster
the processskills of observing,comparing, ordering, relating, inferring, applying, categorizingand
communicating.The sevenbasicconceptsof ecologyare easilytaught through the use of EV materials.
The California state framework themes(currently undergoing a revision to fit the newest science
standards),energy,stability,evolution,patternsof change,scaleand structure,and systemsand
interactionscanbe readily presentedthrough our programs.
BAY ECOLOGY GUIDE OBJECTIVES
This guide is intended to further understanding of the Environmental VolunteersBayEcologyProgrnm
and leaming stationactivities.Through the use of this guide and the suggestedreadings,volunteers
will be ableto better understand,and generatein othersan appreciationfor the Bay'secology,speci{ic
organismsand human interaction with the environment.
INTRODUCTION
The SanFranciscoBay is a rich and complexecosystem.It is composedof five basicnatural
communities:open water estuary,mud flat, salt marsh (composedof both seasonaland tidal wetlands),
salt pond, and a drier upland area.Thesemakeup the natural environmentof SanFranciscoBay.This
estuaryis inhabitedby a diversepopulation of plants and animals.How this estuarywas formed, what
specieslive here and why, and how humans have affectedthis unique environment will be briefly
covered in this guide.
A GEOLOGIC HISTORY OF SAN FRANCISCO BAY
HOW THE BAY WAS FORMED
Near the end of the Pliocene epoch (1 to 4 miilion years ago), a
mountain range began forming along what is now the OaklandBerkeley hills. This upheaval caused the original bay to be sealed off
15,000yearsago
from the ocean. At the same time the Sacramento River began
forming a new route to the sea, cutting through the mountain range at
what is now the Carquinez Strait. The southern end of the bay was
creating new drainage patterns. The surface of the southern basin was
crossed by bedrock ridges of 100 million-year-old Franciscan rock.
These ridges rose from 200 to 300 feet. Some are currently buried
beneath bay mud; others have formed familiar landmarks such as:
Potrero San Palo, west of Richmond; Coyote Hills near Newark Angel
and Alcatraz Islands; Red Rock near the San Rafael Bridge; Albany Hill
and San Mateo Point.
10,000yearsago
As the weather began to warm (225,000 years ago), the melting glaciers
caused the sea to rise. The water crept through the Golden Gate,
submerging the deep river gorge and valleys, and creating tidal
marshes. Northern Santa Clara Valley was flooded by the encroaching
ocean, forming the San Francisco Bay and depositing mud over the
eroded bedrock. Some time after this flooding and mud deposition
(about 100,000years ago), the weather cooled, glaciers advanced and the
sea level lowered again, causing the newly-deposited mud to harden.
About 20,000 years ago (after the last glacial period) the ocean reflooded the bay. The rate of flooding was fast in geologic terms, about
one inch a year. For several thousand years sediments accumulated
along the shallows; a second, thicker and softer young bay mud
covered the ancient sea bed. The large expanse of tidal mud flats and
marshes that were created by the accumulated sediments offered a
haven for a diverse population of organisms.
The watershed of the San Francisco Bay (estuary) covers 40 percent of
California and extends northward to Oregon. An estuary is a partially
enclosed body of water where the outflow from rivers meets and
mixes with the influx of ocean water. As much as half of the surface
water in California begins as rain or snow; at least one half of this
water fall is diverted for use on farms, in factories and homes. The
remainder flows through the delta to the largest estuary on the west
coast of North America. 1
T}re deepest point in the San Francisco Bay is under the Golden Gate
Bridge, where the submerged river cut a path to the ocean; water depth
here is 350 feet. However, most of the bay is shallow. Seventy Percent
is less than 18 feet deep, especially in the eastern and southern
portions of the South Bay and the northern portions of San Pablo and
Suisun Bays. Along the South Bay sediments are mixed with oyster
shells, but elsewhere the estuary's bottom is coated with an ooze of
fine silt - commonlv referred to as bav mud.
Bay Guide
page 1
A GEOLOGIC HISTORY OF SAN FRANCISCO BAY
WATERCONDITIONS
Hydrologists split San FranciscoBay into two distinct areas:a northem stretch
from the delta through Suisun, San Pablo and Central Bays,where salinity levels
are in{luenced by flows from the Sacramentoand San Joaquin Rivers. The second
areaconsistsof [he South Bay which receiveslessfresh w^ater,about one-tenth
less,than the northern area.Consequently,the South Bay's salinity levels are
higher. During the summer months, becauseof evaporation, salinity may be
higher in the bay than in the ocean.
Semi-diurnal tides (two low and two high tides of unequal height approximately
every 24 hours), affect the ecologyof the bay. An averageof 1250thousand acrefeet (onefourth of the bay's total volume) of seawater flows in and out of the
bay during eachtide cycle. In contrast,the averageflow of freshwater into the
estuary is about 50 thousand acre-feet.
The bay had reached its maximum size about 10,000years ago and remained
basically unchanged until the arrival of Spanishmissionariesand ranchers.
SOME BASIC ECOLOGICAL CONCEPTS
The bay is a valuable resourcefor all of us. Marshes serve as nafural air and
water purifiers. Marsh plants can remove carbonmonotde from the air and
produce large quantities of oxygen and carbon dioxide. They filter small amounts
of sewageand other pollutants from the bay'swaters.We must rememberthat
we, too, are a thread in the vast food web encompassingall the life residing in
and around the bay. Understanding the following basic ecologicalconceptswill
help us appreciatethe complexity of the web.
1. ALL LIVING THINGS DEPEND (directly or indirectly) ON EARTH, AIR,
SUN AND WATER FOR SURVIVAL
Earth:soiltype, topography,degreeof slope,pH, exposureand nutrients.
Air:oxygen and other gases,wind, wind-bome particles.
Sr:n:degreeof heat, Iight and energy.
Water:ascontained within earth and air, as interacting with heat and light, as
a solvent for nutrients and gases,as a medium for life forms, as a chemical
to maintain intemal physiological functions.
2. LIVING THINGS ARE ADAPTED TO THEIR ENVIRONMENT; THEY
CHANGE AND MAKE CHANGE (changeoccurs over time)
Living organisms adapt, are modified by and interact with their physical
environment.
Living organismsmodify their physical surroundings by their various
interactions.
3. LMNG THINGS DEPEND (directly or indirectly) ON OTHER LIVING
THINGS FOR SURVIVAL
Organisms interact with other organismsin order to survive.
Organisms are interdependent.
4. AtL LIVING THINGS HAVE A NICHE WITHIN AN ECOSYSTEM
Organisms have specific roles within an ecosystem,this createsa niche
(specialrole and space)within their habitat.
The variety of organismsin their niches and habitats within an ecosystem
comprise a community.
page 2
Bay Guide
SOME BASIC ECOLOGICAL CONCEPTS
5 . LIVING THINGS ARE PRODUCERSOR CONSUMERS
Producersprovide the basicenergywithin a food web. Theseare plants and
are consurnedby first order consurners.
Consumersmay eat live producers/consurneother live consumersor consulne
dead or decayedorganiCmatter. Top consumersare predators and not
usually prey; in a food pyramid they are at the top.
6. MATERIALS ARE RECYCIED, ENERGY IS TRANSFERRED IN
DIFFERENT FORMS
Organic and inorganic matter is transferred through a variety of methods and
forms.
Original energy from the sun is transferredby plants through photoslmthesis
to first order consurners.
Dead matter is broken down into simpler materialsby decomposers.
Energynot utilized by various forms such as invertebrates,fungi and bacteria
is releasedas heat.
7. HUMANS ARE DIRECTLY RESPONSIBLEFOR THE HEALTH OF THE
PLANET
Humans servea role within eachindividual's community and, hence, affect
global environments.
Becausehumans are capableof manipulating the environment, we can
becomeaware of our impact on the community.
Eachone of us must, to the best of our ability, make our impact positive by
minimizing or eliminating environmental degradation.
Source:Dr.Diane Conradson
AN OVERVIEW OF SAN FRANCISCO BAY ECOSYSTEMS
An ecosystertis defined as "a community of plants and animals and the
environment with which it is interrelated."An aerial view of the bay highlights
distinct ecosystems:areasthat are coveredwith water and those that are not.
Theseareasare divided into open water, salt marsh, mud flat, salt pond and
upland. The bay itself is approximately5-5miles tgle grrd from 3 to 12 miles
*ide. Theseecosystemswilt Ue describedalong with the associatedanimal and
plant tife.
INTRODUCEDSPECIES
An estimated one hundred non-native speciesreproduce in the San Francisco
Bay. Many exotic plants and anima]ghave-beenparticularly successfulin their
adiptatioir to a ndv environment. The lack of competition and an abundant
food supply has enabledthem to gain a stronghold in their particular niche.The
quoyanacausespickleweed-destructionwith its burrows that
isopod bphoeroma
hastenerosion.The red foxVulpesfulaa feedson the eggsof the endangered
California clapper rail (Rallrclongirostriil.
AN OVERVIEW OF SAN FRANCISCO BAY ECOSYSTEMS
Many other introduced specieshave been successfulin adapting to the bay;
some of them are listed below.
SOME EXAMPLES OF INTRODUCED
SPECIES
Plants
Brass buttons Cotula coronopifolia
Star thistle Centaureasolstitialis
Animals
Invertebrates
Soft-shelled clam Mya arenaria
Japaneselittle-necked clam Tapes philippinarum
Mud snail Illyanassa obsoleta
Tube worm Streblospiobenedicti
Vertebrates
Stripsd bass Morone saxatilis
Mosquito f.ish Gambusiaat't'inis
Easternbullfrog Rana catesbeiana
Ring-neckedpheasant Phasianuscholchicus
Red fox Vulpes fulaa
ABOUT THE BIRDS
The variety of birds that inhabit the bay at various time is arnazing, A Iarge
number spend the entire winter here; as many as 281 species have been
identified. Some of the avian residents winter in the marshes, while others
nest here but winter in warmer climates. The rest of the birds are migratory. It
is estimated that over two million birds migrate through this South Bay area
on the Pacific flyway, coming from their breeding grounds up north to winter
in southern climates. Some birds are perrnanent residents; others winter in
the marshes. Some only nest here; other species stop off briefly to rest and
feed.
Birds visiting and inhabiting the San Francisco Bay area are all specifically
adapted to the type of food they eat and the type of habitat (open water, mud
flat, salt marsh, salt pond, or upland) they occupy. Many of these adaptations
are modifications to the birds' beaks and feet. Figure #1 shows the variety of
these adaptations.
Different species of birds usually do not compete for the same food.
Shorebirds, though often feeding together, are not looking for the same food.
One species may have a longer bill and probe deeper. Another species may
have longer legs enabling it to feed in deeper water. Baylands birds can be
loosely divided into four groups based on their food preferences: invertebrate
and vertebrate eaters, filter feeders and scavengers. Some examples are listed
below.
page4
Bay Cuide
AN OVERVIEW OF SAN FRANCISCO BAY ECOSYSTEMS
Invertebrate Eaters
American avocet Recurairostraamericana
Black-neckedstilt Himantopus mexicanus
Willet Catoptrophorussemipalmatus
//
Marbled godwit Limosafedoa
Killdeer Charadrius aocit'erus
d'
(Woodpecker)
CLIMBING
Western sandpiper Ereunetesmauri
a
\/*
/r
#
-
JS*MMTNGWEB
WADING (Heron,Avocet)
PERGHfNG(Sonsbird)
Bhck-shouldered
CATCHING PREY{Hawk, Owl)
HOOKED (Baptors)
Catching PreY,Meat
Ea le r s,CH I S E LS HA P E D
(Vvoodpeckers)Tree Drilling
Vertebrate Eaters
Northern harrier Circus cyaneus
rHtcK (Finch)
{ts"o*-,
\ Seed Crushing
/
/\-;( -
tF4.
\-
klte Ela-nus caeruleus
Burrowing owl Athene cunicularia
American kestrel Falco sparaerius
Red-tailed hawk Buteojamaicensis
Great egret Casmerodius
albus
Snowy egret Leucophoyxthula
Great blue heron Ardea herodias
Forester'stern Sternaforsteri
Caspian tern Hydroplogne caspia
Filter Feeders
Shoveler Spatula clypeata
LONG-SLENDER(ShoreBirds)
Mallard Anas platyrhynchos
Mud Probing, Crustacean Eaters
Ruddy dwck Oxyura jamaicensis
Cinnamon teal Anas cqanoptera
SLIM SHARP (Swallows)
Scavengers
Gulls Larinae (aarieties)
Western gull Larus occidentalis
Turkey vulture Cathartesaura
Figure #1
OPENWATERESTUARYECOSYSTEM
Rather than being a true bay, San FranciscoBay is actually California's largest
and best-known estuary. An estuary is a unique ecologicalsystem where fresh
and salt water come together and mix. Salt water from the Pacific Oceanand
fresh water from rivers are mixed by winds and tidal currents.The bay
provides the only outlet to the sea for the 60,000-square-mile
Central Valley
and its rivers. Of the sixteen rivers that flow into San FranciscoBay, the
principal ones are the Sacramentoand the San Joaquin Rivers.
Bay water is termed brackish;its salinity is generally between 27,000to 29,000
parts per million (ppm) total salt. This compareswith 1,000ppm for drinking
water and 34,000ppm for normal sea water. Fresh water feedsinto the bay
from the San ]oaquin-SacramentoRiver systems.Water temperature
averages about 62 " Fahrenheit, with extremes of 55 ' F in the winter and
70 o F in the summer.
it
Bay Cuide
page5
AN OVERVIEW OF SAN FRANCISCO BAY ECOSYSTEMS
OPEN WATER ESTUARY ECOSYSTEM (contiNUed)
Marshlands, tidal shallows, and deep-water areas produce a variety and
abundance of fish and wild life. At low tide, 707o of the bay is less than 18 feet
deep. However, there is a deep-water channel about a mile wide and about
forty feet deep. This central channel extends almost to the town of Alviso.
The open bay waters are home to many speciesof aquatic animals. Fish such
as sharks, anchovies,sculpins, striped bass,and top smelt are born in the
marshlands and shallow areasbordering the bay. The bay is a vital haven to
many forms of wildlife.
Experts estimate that as many as a million water fowl rest and feed in the
marshes during the winter months. Migratory birds fly thousands of miles
from their breeding grounds in Arctic Canada and Alaska to winter in Baja
California or South America. For hundreds of years/ these birds have
followed the Pacific flyway. It is estimatedthat the bay furnishes food, shelter
and resting placesfor approximately 70Voof the water and shore birds which
migrate along the Pacific fly*uy.In the 1940'san estimated 20 million
migrating water fowl used the Pacific flyway. In 1990the count was estimated
at 2.5 million; this reduction is due to a number of factors all of them related
to human population density. About 75 different speciesof water and shore
birds have been identified in the bav's area.
OPENWATERESTUARYPLANT ANID A}IIIVT\L SPECIES
Plants
Diatoms (aarieties)
Kelp
Sea weed Enteromoraha
Bird Migration Along the Pacific Flyway
Animals
Invertebrates
Copepods Copepodnauplii
Bay shrimp Crangon californiensis
Gem clam Gemm gemma
Vertebrates
Leopard shark Triakis semifasciata
Bat ray Mylobatis caliornica
Starry flounder Platichthysstellatus
Top smelt Atherinops at'finis
Northern anchovy Engraulismordax
Shiner surf perch Cymatogasteraggregata
Three spined sticklebackGasterosteus
aculeatus
Staghorn sculpin Leptocottusarmatus
Bay pipefish Syngnathusleptorhynchus
Striped bass Morone saxatilis
Forester'stern Sternaforsteri
Caspian tern Hydroprogne caspia
page6
Bay Cuide
AN OVERVIEW OF SAN FRANCISCO BAY ECOSYSTEMS
OPENWATERESTUARYECOSYSTEMKontinued)
Vertebrates
Western grebe Aechmophorusoccidentalis
Canvasback Aythya aalisineria
Ruddy duck Oxyura jamaicensis
Brown pelican Pelecanusoccidentalis
California gull Larus californicus
Double-crested cormorant Phalacrocoraxauritus
Harbor seal Phocaaitulina
MUD FLAT ECOSYSTEM
Mud flats lie between the salt marsh and the deeper estuary waters. The
casual observer may think there is little life present in this area. However,
there is an abundanceof life in the mud. The burrows and siphon holes of
benthic(bottom dwelling) animals proliferate in the mud. These include
snails, clams, oystegs,mussels,isopods,crabs and polychaeteworrns. As plants
decomposeto form detritus, they are eatenby these mud dwellers. These
animals burrow to protect themselvesfrom wave action, dehydration and
predators. In turn, these animals provide food for fish and other wildlife. The
mud may be green due to a marine algae called sealettuce.
1<
As soon as the tide goes out a feeding frenzy of shorebirds invades the mud
flats. Various shore birds appear on the mud flats. The long legs of willets,
avocetsand stilts hoid them well above the shallow water, whiie their long
beaks probe for food. Hurrying along the exposed mud flats, the shorterlegged birds appear, the sandpipersand killdeers. Thesesmall birds dart about
the mud looking for food. Avocets sweep the surface for small clams, piovers
peck for worrns/ and dowitchers and willets probe the mud for different
insectsand isopods.
Only three of the shorebirdsseenat the baylands nest in the mud flats. They
are the killdeer, avocet and black-neckedstilt. They are dependent on salt
grass for their nesting areas.
)\
MIID FLATPLANTAND ANIMAL SPECIES
Plants
Anaerobic bacteria Bacillus
Sea lettuce UIaa lactuca
Cord grass Spartinafoliosa
Eel grass Zosteralatifolia
Pickleweed Salicorniaeuropeaor airginica
A nimals
Invertebrates
Diatoms (varieties)
Fat innkeeper worm Urechis caupo
\l
Phoronid worms Phoronis(varieties)
Nematodes(round worms)
Tube worm Streblospiobenedicti
Ghost shrimp Callianassacalifornienis
Ribbed mussel Ischadiaumdemissum
Mud snails llyanassaobsoleta
*'*K
\ 1?r'
BayGuide
%
pageT
AN OVERVIEW OF SAN FRANCISCO BAY ECOSYSTEMS
MUD FLAT PLANT AND ANIMAL SPECIES(continued)
Animals
Invertebrates
Bent nose clam Macoma nasuta
Ribbed mussel Modiolus demissus
Mud crab Hemigrapsusoregonensis
Vertebrates
Killdeer Charadrius aociferus
Black-bellied plover Squatarolasquatarola
Short-billed dowitcher Limnodromusgriseus
American avocet Recruuirostraamericana
Black-neckedstilt Himantopus mexicanus
Willet Catoptrophorus semipalmatus
SALT MARSH ECOSYSTEM
Salt marshesserve as a transition zone between the open water of the bay,
mud flat and the dry upland areas.They are most noied for the abundant
plant life that grows on their saltp water-logged soil. Salt marshesare subject
to flooding by the high tides that occur twice every day. Salt marshesusually
form in the zone between the highest high tide and the mean tide levels.
The soil in a marsh is very salty. Most plants cannot grow in salty soils
becausethe salt will literally suck fresh water right out of them. However,
some plants called halophytes(salt-plant) have become adapted to a salt
marsh. They either excretethe salt through special cells (sfomata) or are able
to keep salt out of their root system.Halophytes are also adapted to being
submergedby tidal waters part of the time. Theseplants, though adapted to
getting their "feet" wet, are limited in the length of time they can be wet. Salt
marsh plants grow in distinct zones.Each zone is dominated by a particular
plant species.The distribution of each speciesis primarily determined by the
duration of submersion.The amount of salt in the soil and water also
determines plant distribution.
Salt marshes are dominated by three plants:
Cordgrassis one of the two most abundant plants in the marsh. It grows in
the wettest part of the marsh closestto the bay waters, at the boundary
between the mud flats and the sait marsh. This plant survives high salt
concentrationsby distilling water through special glands called stomata,
leaving salt crystals on the leaves.Cordgrassforms the first link in many food
chains involving hundreds of animals that live in the bay. By fall, cordgrass
has grown to a height of four feet and resemblesa small corn plant. When it
dies, almost all of the grass decomposesinto minute particles called detritus,
or "bay soup." Theseparticlesare food for bacteriaand young bay animals
which, in turn, are eatenby larger forms of life. Cordgrassproduces five to ten
times as much nutrient materials and oxygen per acre as wheat.
page8
BayCuide
AN OVERVIEW OF SAN FRANCISCO BAY ECOSYSTEMS
SALT MARSH ECOSYSTEM(continued)
Pickleuseedis another dominant marsh plant, growing in a higher and drier
marsh zone. This gray-green succulent begins growing where the cordgrass
stops. The compressed leaves look like a series of slender pickles attached end
to end. Pickleweed tolerates having its "feet" wet by high tides, but grows
above the average iow tideline. The stored salt builds up in the "pickles" until
fall, when the end "pickle" turns pink or red, dries up and breaks off-
Pickleweed thrives in soil of up to 6Vosalinity. During the summer months
you may seea conspicuous,bright orange hair growing on the pickleweed.
These hairs are actually the stems of a parasitic plant called marshdodder.IL
attachesitself to the pickleweed by inserting small knobs into the pickleweed
which bring food from the pickleweed to the dodder.
Salt grassgrows in the zone above pickleweed. Like cordgrass,it excretessalt
from its leaves by means of special glands. Other plants also will grow in this
zor\e,including the Australian salt bush (which provides shelter for the
pygmy blue butterfly and food for its larvae), fat hen and alkali heath.
Birds of prey that are dependent on the salt marshesfor their food are the
black-shouldered kite, northern harrier, red-tailed hawk, American kestrel
and burrowing owl. Their favorite diet is meadow mouse, ground squirrel,
gopher and rabbit, aithough the kestrel will eat insects.Most of thesebirds
prefer to nest in the foothills of SantaClara county., although the blackcrowned night and blue herons nest on Bair Island near Redwood City.
The salt marshesare inhabited by several endangeredspecies,the California
clapper rail, the red-bellied salt marsh harvest mouse, the black-shouldered
kite, the pygmy blue butterfly. The clapper rail and harvest mouse may be
observed during high tide when forced out of their habitats.
Stands of cordgrassgrowing near the water's edge serve as nesting grounds
for the endangeredCalifornia clapper rail. On slightly higher land among the
pickleweed are the nests of waterfowl, salt marsh song sparrows and coots.
The red-bellied salt marsh harvest mice are found nowhere else except in the
San FranciscoBay marshlands.Thesemice make a nest of dry pickleweed and
can drink salt water, excretingthe excesssalt in their urine. They serye as a
major source of food for the northern harrier (a major predator of the salt
marsh). Shrews and other mice speciesalso inhabit the same area. Shrews are
the smaliest of the mammals living here. They feed on insects of all sizes and
eat continuously,day and night.
'{it\
43
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Bay Guide
page9
AN OVERVIEW OF SAN FRANCIqCO BAY ECOSYSTEMS
SALT MARSH PLANT AND ANIMAL SPECIES
Plants
Algae
Cordgrass Spartinafoliosa
Pickleweed
airginica and europea
-Salicornia
Marsh dodder
Cuscutasallna
Salt grass Distichlis spicata
Sea arrowgrass Triglochin maritima
Cl.ly dock Rumex crispus
Alkali heath Frankenia grandifolia
Gum plant Grindelia humitis
Fat hen Atriplex patula
Australian saltbush Atriplex semibaccata
Fennel Foeniculum aulgare
_r,
t1ffi\
YtH
g
,f
naoo'1
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Animals
Invertebrates
BarnacleBalanus
Salt marsh
logquito Aedessquamiger,A. dorsalis
Larvae Brine fly
Ephydri
Tiger swallowtail papilio rutulus
Pygmy blue butterfly Brephidium oxilis
Vertebrates
pupa Mud goby Cleaelandiaiox
_Long_jawmudsucker Gillichthys mirabillis
Leopard shark Triakis semifasciata
Flounder platichthyes flesui, p. stellatus
American avocet Recurairostraamericana
Black-neckedstilt Himantopus mexicanus
Willet Catoptrophorussemipalmatus
Marbled godwit Limosafedoa
Killdeer Charadrius aociyerrs
California clapper rail Rallus longirostris
Sanderling Crocethiaalba
Western sandpiper Ereunetesmauri
Common goldeneye Bucephalaclangula
Great egret Casmerodius
albus
S_nowyegret Leucophoyxthula
Great blue heron Ardea herod,ias
Black-crownednight heron Nycticorax nycticorax
Shoveler Spatulaclypeata
Mallard Anas platyrhynchos
Cinnamon teal Anas cyanoptera
Norther harrier Circus cvaneus
Burrowing owl Speotytocunicularia
Red-winged blackbird Agelaiusphoeniceus
Song sparrow Melospiza-melodia
White-crowned sparrow Zonotrichia leucohhrys
Savannah sparrow passerculussandwichensis"
Jack rabbit Lepus calit'ornicus
---EaGae
AN OVERVIEW OF SAN FRANCISCO BAYECOSYSTEMS
SALTMARSH PLANTAND AMMAL SPECIES(continued)
Vertebrates Gontinu ed)
Red-bellied harvest mouse Reithrodontomysraaiaentris
Salt marsh harvest mouse Reithrodontomysmegalotis
San Franciscogarter snake Thamnophiselegans
Gopher snake Pituophis catenifer
SALTPONDECOSYSTEM
If you were to take an airplane ride over the southern end of the bay, you
would notice a mosaic of different colored ponds. The different colors are due
to the many varieties of algae and aerobic bacteria that thrive in varying
concentrationsof brine (salty water). Generally, red water indicatesa very
high level of salinity; the less saline ponds are blue or green.
Naturally occurring salt-evaporationponds have been in existencefor
centuries.Local Native Americans used the salt residue to barter for goods. In
1854the first man-madeponds were built by ]ohn Johnsonin Hayward. In
1936Leslie Salt Co. becamethe owner of these man-made salt ponds. Salt
ponds comprise about sixty square miles of diked habitat. Although manmade, the salt pond habitat has become important to the survival of many
organisms.Many speciesof wintering birds are dependent on the salt ponds
for food. As the water evaporatesthe salinity increases;2 miilion tons of salt
are produced annually in a processthat takes 5 to 7 years to complete.Salt
grass can survive in the less salty ponds along with the insect, water boatman.
As the salinity increasesfewer speciesare found that can survive. Bacteria,a
specially adapted algae,brine shrimp and flies comprise the baseof the salt
pond's food pyramid. Black-neckedstilts and avocetshunt for brine shrimp,
while along the pond's edge snowy plovers snap up brine flies. Both avocet
and black-neckedstilt populations have increasedbecauseof the additional
food supplied by the ponds. The dried out ponds and the leveesalso provide
valuabie nesting sites.
SALT POND PLANT AIVDAlvIIv{r{LSPECIES
Plants
Algae Dunaliella salina
Salt grass Distichlis spicata
SALT POND PLANT AND AMMAL SPECIESkontinued)
Animals
Invertebrates
Bacteria fuarieties)
Brine shrimp Artemia salina
Brine fly Ephydra
Water boatman Arctocorixa interrupta
Salt marsh mosquito Aedessollicitans
Vertebrates
Black-neckedstilt Himantopus mexicanus
American avocet Recurairostraamericana
Bay Guide
page 11
AN OVERVIEW OF SAN FRANCISCO BAY ECOSYSTEMS
UPLAND ECOSYSTEM
The San FranciscoBay and the surrounding land are no longer in a "natural"
state. Human impact has forever altered the face of this environment. As a
result of humans draining marsh land and also becauseof natural drainage,
there is a large, surrounding, drier area around the bay called an upland
environment. Many of the plants growing here are not natives, such as
European grasses,eucalyptusand acacia.They have establisheda niche by
being vigorous and aggressive,and not having much competition for space.
The non-native red fox and ring-necked pheasant live alongside the native
jack rabbit, gopher snake, ground squirrel and northern harrier. The snowy
egret, great egret and the great blue heron build their nests on higher growing
plants such as shrubs or trees.All of thesespeciesare adapted to the open, flat,
dry and windy upland ecosystem.
UPLAND ECOSYSTEM PLANT AND ANIMAL SPECIES
PlanLs
Bunch grass
Wild oats Aaena fatua
Sticky monkey flower Mimulus guttatus
Mustard Brassicacampestris,B. nigra
Plantain Plantago hirtella
Curly dock Rumex crispus
Hemlock Conium maculatum
Fennel Foeniculum aulgare
Soap root Chlorogalum pomeridianum
Thistle Cirsium araense
Gum plant Grindelia humilis
Horehound Marrubium aulgare
Coyote bush Baccharispilularis
California laurel Umbellularia californica
Alder Alnus oregona
Animals
Invertebrates
Pyg*y blue butterfly Brephidiumoxilis
Tiger swallowtall Papilio rutulus
Cabbagebutterfly Pieris rapae
Mosquito Aedessquaiger
Crane fly Tipula triuittata
Vertebrates
Gopher snake Pituophis catenit'er
Western fence lizard (blue belly) Sceloporusoccidentalis
San Franciscogarter snake Thamnophiselegans
Pigeon (rock dove) Columbialiaia
White-crowned sparrow Zonotrichia leucophrys
Savannah sparrow Passerculussandwichensis
Barn swallow Hirundo rustica
House finch Carpodacusmexicanus
Brown towhee Pipilo fuscus
page72
Bay Cuide
AN OVERVIEW OF SAN FRANCISCO BAY ECOSYSTEMS
(continued)
UPLAND ECOSYSTEMPLANTAND ANIMAL SPECIES
Vertebrates
Loggerhead shrike Lamius ludoaiciannus
Anna's hummingbird Calypteanna
Northern harrier Circus cuaneus
Red-tailedhawk Buteojamaicensis
Burrowing owl Speotytocunicularia
Turkey vulture Cathartesaura
Black-tailed jackrabbit Lepus caliornicus
Striped skunk Mephitis mephitis
Ground squirrel Citellus beecheyi
California vole Microtus californicus
HUMAN INTERACTION WITH SAN FRANCISCO BAY
HLIMAN HISTORY
Native Americans inhabited the bay's shores for at least 3500 years. It is
estimated that as many as 75,000 people inhabited the area of San Francisco
Bay when the Spanish explorers first arrived. The abundance of food and the
year-round mild climate offered these people the opportunity for a relatively
rich and easy life. They left evidence of their existence in the remains of some
400 shell mounds scattered around the bay. However, their impact on the
environment was minimal.
In the last 150 years,alterations of the bay have not been so much from
geologic forces as from human intervention. The original delta's 350,000acres
of freshwater marsh were diked and planted with crops. Its waters have been
severely polluted and over 60voof the bay has been filted with garbageor
Ieveed off from tidal action. In 100years,the larger bay territory has decreased
from 720 to 480 square miles. In the process,many fishery resourceshave
been lost and valuablewildlife habitat and recreationspacehave been
destroyedor altered.'
Bay Cuide
page13
HUMAN INTERACTION WITH SAN FRANCISCO BAY
HUMAN HISTORY(continued)
In 1769,the Spanishexplorer Gaspar de Portola, 63 men and 200 horses,
camped on the north bank of San Francisquito Creek near the tree El Palo
Alto. He was searchingfor Monterey Bay, but instead found San Francisco
Bay. Five years later, in 1774,Captain Rivera and Father Palou planted a cross
on the creek bank near this spot, considering it a fine site for a mission.
San FrancisquitoCreek was navigable, so a landing was built about a half mile
upstream from the bay. Lumber, hides and taliow were transported along the
creek from the back country to be loaded aboard vesselsmoored at the
landing. Materials were transported up the bay to the growing city of Yerba
Buena which would soon become known as San Francisco.
In 1851the Stateof California passedthe first of a seriesof statutes
authorizing the salg of swamp and later tidelands. The object of the statute
was to "reclaim" bay land which was considered worthless in its natural state.
People took advantageof this law and began acquiring salt marshesand other
bay land, which were routinely filled for the development of farms.
The Gold Rush caused some of the earliest, major destruction of the
California environment. The technique of hydraulic mining blasted hillsides
with powerful jets of water. It is estimatedthat by "1884,
when this processwas
finally banned, over a billion cubic yards of sediment were washed
downstream and deposited in the northern portions of the bay. Eventually
sediments flowed southward causing massive population depletion of oyster
beds (Seefigure #3 below).
Key
Salt marsh before 1800's
Salt marsh today
Open water today
\/
-l /4 -
San Francisco Bay
ta?
Be d w o o d
Clly
-
t.,i.1
" " n 'o
\{
'r.\/
-
\
\ Pato atro
]
\
'
"")","')"*
\
figure #3
page74
-:--
Bay Cuide
HUMAN INTERACTION WITH SAN FRANCISCO BAY
EFFECT OF HTIMAN IMPACT
Ever since the first settlers hauled some dirt from the bottom of Telegraph
Hill to fill in Yerba Buena Cove for a waterfront port, humans have been
reshaping the bay's shore, extending it outward and changing it in various
ways. Much of the financial district of San Francisco and the Marina District
were once under water. Other cities soon followed San Francisco's example so
that the bay's original area was diminished by filling and diking. Of the
original 720 square miles of natural marshland, oniy about 75 square miles
are left (Seefigure #3, page14).SanFranciscoBay was consideredby many to
be largeenoughthat filling one small sectionwould not endangerit. San
Franciscoand Oakland airports, FosterCity, the BayshoreFreeway and
TreasureIsland are some examplesof developments built on filled lands to
satisfy the needs of a mushrooming population.
Major bayfill is often an accumulation of domestic garbage.There are more
than nine garbagedisposal sites around the South Bay. Walls or leveesare
built around some of the marshesand tidelands for disposal sites. The water
is then drained out so garbagetrucks can dump their loads. After about eight
feet of garbageis dumped at the site, two feet of dirt is put on top of the
garbage.l-and used in this manner is called a "sanitary landfill." The disposal
sites are not only unattractive but can be a source of poliution and representa
loss of wetiand or mud flat habitat. It is estimatedthat over 64Voof landfiil
sites are located on tide and marsh lands. Sometimesthe leveesare poorly
built and refuse spiils into the bay. Since each of us adds oaerfour poundsof
garbagedaily, methods must be found for disposing of our garbage.without
continuing to fill or poilute the bay.
Tlre San FranciscoBay is a giant receptaclefor the sewageof approximately 7.5
n-rillionpeople, for the pesticidewastes washed off of farm land, for the
residue from rain-washed roads and parking lots and for the dischargesof
industry. There are over 80 waste water outlets into the bay, discharging eight
hundred miilion gallons of waste water daily. Waste water still includes
many organic solids, as well as oil, grease,phosphates,mercury (in small
amounts) organic chlorine, heavy metals,selenium,PCB'sand microorganismswhich are dumped directly into the shallow waters of the bay. A
clirectrelationshipexistsbetweenthe amount of toxic material discharged
into the bay and the lack of organismsessentialto the natural food chain.
Tire bay is not only shrinking, it is also lowering. Each year the land mass
sinks a couple of inches. Becauseof human and industrial consumption, the
water table (underground water supply ) is being depleted much faster than it
can be replaced;recent drought has only exacerbatedthe problem. The result
is an increasein the intertidal mud flats and a change in the delicatebalance
betrveenthe various bay ecosystems.
Filling and adding wastewater to San FranciscoBay will continue to have
dramatic effectson the surrounding environment and the organismsthat are
on that environment.The following are just a few ways that the
c'lependent
degradationof the bay affectsthe quality of life for all.
Bay Guide
page15
HUMAN INTERACTION WITH SAN FRANCISCO BAY
EFFECTOF HUMAN IMPACTkontinued)
Destructionof Wildlife
Fish and wiidlife can exist only where the habitat meets their needs.When
salt marshesare destroyed,few speciesshow the ability to adapt to different
habitats.If wetlands bordering the bay are destroyed,a high percentageof
the birds migrating along the Pacific flyway may be jeopardized.California
has lost more of its wetlands than any other state. More than 67voof San
FranciscoBay's wetlands have vanished due to housing developments,
airport runways/ garbage dumps, industrial parks, and marinas.
Decline in Water Ouality and ChemistrJr
Not only must animals' homes be preserved, but they must be maintained
in an unpolluted condition. Bay filiing can result in chemical reactions
which releasepollutants into the water severely reducing the amount of
oxygen in the water, killing fish and other organisms. Storm sewers' general
runoff during normal weather conditions will be treated before discharge
into the bay. However, becauseof the increasedvolume of water during
storms, some untreated storm water will be discharged directly into the bay.
Toxins dumped down sewersduring dry weather may accumulateand be
washed out into the bay during heavy rainfall.
Another aspectof the change in the bay's chemistry is alteration in salinity
Ievels due to increaseddemands for fresh water from growing populations
and from agricuitural use which resulted in less fresh water for the bay.
Climatic Changes
If a major portion of the bay were filled, there would be changesin the
climate. The wind would be slower since wind velocity is higher over
water. Cooling summer breezeswould not blow as far south and east;
temperafures would rise and smog would be intensified.
RecreationLoss
By the year 2020,a projected 15 million people will be living around ihe bay.
Open spacefor hiking, boating, bird watching, and fishing will be in greater
demand. The bay should be available as a place for all to visit and enjoy.
Fortunately, an increasingamount of the bay's 276-mile shoreline is being
made available to the public for thesepurposes. It is important that we keep
these recreationareasin pristine condition.
Earthquake Hazard
Filled lands can look stable,but tend to sink as the soil particles shift and
settle when they are shakenby an earthquake.This processis called
IiquefactionBecausefilled areasare less stable, more damage can occur ro
structuresbuilt on landfills.
HTIMAN INTERACTION
WITH SAN FRANCISCO
BAY
STRIVING TO SAVE T}IE BAY
The 1960's initiated a period of environmental concern, typified by the
establishment of the Bay Conservation and Development Commission
(BCDC) by the Stateof California n'1967. Alarmed at the shrinking of the bay
due to filling, the BCDC was interested in the preservation of the shoreline
for public accessand marsh areas for wildlife. A small group of citizens
recognized the value of South San FranciscoBay, and in 1968formed the
South San FranciscoBay Planning, Conservation and National Wildlife
Refuge Committee. As a result of the efforts of this and other grassroots
organizations,Congressset aside money to buy 23,000acresfor San Francisco
Bay National Wildlife Refuge in 1972.Another 1972 event, the amendment
of the Federal Water Pollution Control Act, allowed $18 billion in grants for
the construction and expansion of thousands of waste treatment plants.
The tri-city (Palo AJto, Mountain View, Los Altos) Regional Water Quality
Control Plant (RWQCP)began operation in October, 1972.The RWQCP has
now increasedto include East Palo Alto, Los Altos Hills and Stanford
University. This facility provides tertiary water treatment of sewage,designed
to remove 9AVoto 97Voof the biochemical oxygen demand (the amount of
dissolved oxygen required by bacteriato decomposeorganic matter), thereby
increasing the amount of dissolved oxygen available to other organisms once
the effluent is dischargedinto the bay. In 799'1,additional coagulating and
filtering were added to produce approximately 1.5 million gallons of
reclaimed water daily. Dischargeof metals has been reduced by 60% of the
1980levels. According to tests of untreated water for hazardous wastes,the
RWQCP continues to find an alarming percentageof heavy metals and other
toxins. Their advice is to save all household hazardous wastes for special
hazardous waste collectiondays.
Tighter government regulations now provide at least some control over
where and how wetlands are developed. Developers are now required to
preserve an equal amount of nafural area for any area that is developed. Two
examples of the results of these regulations are Mountain View's Shoreline
Park and Palo Alto's Bayfront Park. But the fight to save the bay is far from
over, consider President Bush's desire to re-define wetlandwhich would
exclude many areasfrom protection, and many wetlands just outside the San
FranciscoBay National Wildlife Refuge boundaries are currently slated for
development. Although many proposed developments seem small, the bay
must be consideredas a single body of water, a complex ecosystem,in which
seemingly minor fills or waste dischargeshave far-reaching and often
devastatingeffects.
Bay Guide
page17
HOW TO DO AN INTRODUCTION AND CLOSING
PRESENTATION
AN EV CLASSROOM
The initial impressionyou make at the beginningof a presentationsetsthe tone
for your entire visit. Be sure you know your audience,keep your openinq
interesting,informative and brief. The children's curiosity-shotrldbe piqiled
enough:o th9{ are eagerto find out more. The examplesgivenhereire^to be used
as a guide. It's bestto put your messagein your ownworrds this will make it
yours, natural and more enjoyablefor you to do and, therefore,more interesting
for your listeners.
BEFORE YOU GETTO THE CIASSROOM HERE ARE SOME SUGGESTIONS
o Use the Chief'sCheckList to guide you through the necessarysteps.
. Call the teacherto give necessarypre-visit information and confirm dates,
times and room number.
o Know your topic
o Settime limits for introduction,learningstationsand
closing
' Outtine your objectives(desiredoutcomes)and communicatethis to your
team.
o Call your EV assistantsand confirm that they know what your objectivesare,
what they are doing, where they're going , when they are to be there and who is
picking up and droppong off the learning stations.
VISIT- INTRODUCTION
THECLASSROOM
)F
Introduce yourself, EV assistantsand the Environmental Volunteer
organization.
*
Explain the words enuirlnmentand aolunteer.
GradesK - 2
{.
Use Salty, salt marsh harvest mouse puppet, as a way for Salty to tell a
story about where he lives,how he survivesand about his neighbors.
Grades 3 - 6
*
Ask the children what they picture when you say SanFrancisco
Bay
(Using the aerialmap of the bay) (Older childrenshouldknow that our bay is
really an estunry,a mix offresh and salt water.)
*
Show the map of the San FranciscoBay, surrounding water ways and ocean
)t
Ask them to imagine they are big birds that can fly high and seethe
whole state of Califomia.
,T
Ask one child to show the PacificOceanon the map, where their school
or houseis located,the SierraNevada,the SanJoaquinand
Sacramentorivers, and the San FranciscoBay.
*
*
*
Ask the children if they know where the bay's water comesfrom.
Acknowledgeand encourageorderllr responses.
*
Offer additional information as neededabout fresh and salt water sources
Explain the term estuary(write it on tfu board.)
)F
Ask how oceanwater is different from bay or river water.
HOW TO DO A CLASSROOMINTRODUCTION AND CLOSING
INTRODUCTIO N kontinued):
*
Discuss the differences between salt and fresh water.
{.
Ask sfudents if they would drink clean ocean or bay water.
*Ask them if they can guess how plants and animals adapt to living in or
near salt water.
*
Use the ryap_todiscussthe inJluenceof the ocean'swater on the bay and
discussthe Golden Gate ( discussthe influenceof tides with older
children,gr
_ a d e4s-6 . )
:{.
Using the map, discussthe influx of freshwater into the bay.
{.Ask them where freshwater initially comesfrom that goesinto the bay.
*
Ask what kinds of plants and animals are found living in or near the bay.
*Lead
into learning station activities;be sure the classhas been divided
into small groups.
*Ark
th. teacherto be the time keeperfor the leaming stations.
LEARNINGSTATIONS
{.
GradesK - 2, use kits that allow for:
Comparing and describingFeathers(MP - 09),Bay birds (Bl - 11),Fish Study (Bl - 06)
SensoryexplorationFeelyboxes(Bl - 05),Mud (Bl - 07),Camou{lage(MP - 01).
,T
Grades3 - 6, use kits that call for:
Reasoning(why is this like this)Fish Study (Bl - 05),Bay Birds (Bl - 11),Feathers(MP - 09),
Bay Banner (Bl - 02)
Speculation(if this were to happen what would the result be?)Fbod Web (Bl - 03), Beaksand Food (Bl - 01), Wetland In A Pan (Bl - 12),
Winging It (MP - 04), LoathsomeLiter (M - 07).
CONCLUSION
,F
-After leaming station activitiesare finished,allow time to ask children to
tell one thing they leamed about the bay (you probably won't have time to
ask every ctrilA f6r a response.)Or, ask a specificquestionabout eachof
the stationspresented.Example:"\AIholives in the mud?"
*lf
th"r. will be a field trip, take time to give instructionsabout clothing,
and appropriate field trip etiquette.
*Mention somethingspecificfor them to Iook for on the field trip.
(See lenrning station matrix)
fl
/
r'--*-:-
\ t --\
F**
,-#'b
lilritul
GLOSSARY
Adaptation:
'
u11adjustment to environmentalconditions; a modification of an organismor its parts that
helps that plant or animal survive.
Algae:
tiny, non-seed-bearingaquaticplants with chlorophyll often maskedby a brown or red pigment.
Benthos:
animalsthat are in a bottom-dwelling community under a body of water.
Bog:
wet, spongy gtound, with soil composedmainly of decayedvegetablematter.
Biodegradable:
--- ---o
the
,.upableof being broken down to simple compounds,especiallyinto harmlessproducts,by
actionof microorganisms.
Brackish:
somewhat salty water, but'less salty than sea water'
Carnivore:
an organism (plant or animal) that eats meat'
Consumer:
plant matter'
an organism that consumesmeat by preying on animals or consulnes
Ctustacean:
and breathethrough
a classof arthropods that usually live in water, have hard exoskeletons,
gills e.g',crabs,shrimp, and bamacles
Decomposer:
an organism (such as bacteria.o.tfulgt) that retumt,.o*qo-1:tsof
&.i"!UV
organic matter to ecological
f""dittg on and breaking d6wn dead plants and animals.
DeDendence:
- -E
the state of requiring something else for individual survival'
Detritus:
decayingbits of plant and/or animal remains(resemblesgooeymud sometimes)'
Diurnal:
active or occurring in the daytime'
Ecology:
""the study of the interrelationship of organismsand their environments'
Endangered:
threatenedwith extinction'
EStuary:
r
,r
!:l ^l
raarl rrl rr
-r, -.-l ^^-^
^^l r water is regularlv
a partially enclosedbody of water with inlets and outletswhere tidal salt -r,a$n+.i o
mixed with freshwater'
Extinct:
an animal or plant speciesthat no longer exists'
GLOSSARY
Food chain:
a sequenceof Livingorganismsinan ecologicalcommunity in which membersof one level feedon
thosein the level below them and in fum are eatenby thosein the level abovethem,
Food web:
the totality of interactingfood chainsin an ecologicalcommunity.
Habitat:
the place where a plant or animal nafurally or normally lives, often characterizedby a dominant
plant form or physical characteristic(the stream or forest habitat).
Halophyte:
a plant that is specially adapted to survive in salty soil (saltbush, pickleweed).
Herbivore:
an organism that eatsliving plants or their parts.
Interdependency:
mutual dependenceof a variety of speciesof organisms.
Invertebrate:
an animal without a backboneor spinal column.
Larva (plural larvae):
an immature stagethat most insectsand somewater animals pass through after hatching from
an egg and beforebecominga pupa.
Migration:
the act of moving (usually seasonally)from one locality to anotherfor feeding or breeding
Purposes.
Mud flat:
the salty soil area of land betweenthe lowest low and the highest low tide that is flooded with
seawater daily and upon which very few plants grow.
Nocturnal:
active or occurring at night.
Nutrients:
the raw materialsnecessaryfor continuing life processes.
Omnivore:
an organism that eatsboth plant and animal material.
Organism:
a living thi.g.
Plankton:
aquatic plants (phytoplankton) and animals (zooplankton)that drift with the currents.
Photosynthesis:
p.o.esr of plants using light energy combinedwith carbondioxide and water to produce
oxygenand simple sugars.
GLOSSARY
Pollution:
contaminationof the environment,especiallywith human-madewastes.
Predator:
an animal (rarely a plant) that capturesand eatsanimals for food.
Prey:
an animal or plant hunted bv another for food.
Producer:
an organism(suchas a greenplant) which usessolarenergyto convert inorganicsubstancesinto
food (i.e.,it doesnot have to eat)through the processof photosynthesis.
Pup a :
an insectin the non-feedingstage(usuallyimmobile) betweenthe larval and adult stage.
Refuge:
a place that provides food, shelter,and protectionfor the organismsthat live or migrate there.
Salinity:
the concentrationof salt in the water.
Salt marsh:
salt water wetland betweenterrestrialand marine ecosystems;salt marshesmav also be
seasonalor tidal wetlands.
Salt pond:
a human-made,diked off, flat area full of salt water which evaporatesto produce salt.
Slough:
a swamp, marsh or pond which is part of an inlet under tidal in-fluence.
Tide:
the altemate rising and falling of the water in oceans,Bulfs, bays, and estuaries,occurring twice
a day in Califomia, causedby the gravitational attraction of the sun and moon on the earth,
occurring unequally at different placeson the earth.
Upland:
ground elevatedabovethe lowlands,marshlands,or rivers.
Wetlands:
areasthat, at least periodically, have waterlogged soils, support plants adapted to wet soil,
and are coveredor occasionallysubmergedby water. Bogs,freshwaterand saltwatermarshes,
and freshwater and saltwater swamps are examplesof wetlands.
page 22
Bay Guide
SUGGESTEDREADING
Bakker, Elna.An IslnndCalledCalifornia.lg7l,IJnlersity of Califomia Press,Berkeley.
Northem California Community College
ATraael Course.1981,
BayOdyssey,
Capman,J. SanFrancisco
Leaming Consortium.
Comell, J. SharingNaturernith Children.7979,Ananda Publications,Nevada City, Califomia'
of Nature.Tggl,DawnPublications,NevadaCity,Califomia
Comell, J.SharingtheJoy
3rd edition, San FranciscoBay Wildlife Society,
Conradson,Diane R. ExploringOur Baylnnds.1996
California.
National Wildlife
"EndangeredSpecies:Wild & Rare,"1987,Rangu Rick'sNatureScope.
D.
C.
Federation,Washington,
National Wildlife Federation.
"Wading into Wetlands," 1986, RangerRick'sNatureScope.
D.C.
Washington,
Jacobson,Yvorne. PassingFormsand Enduring Values.1984,TiogaPress,Menlo Park, Califomia.
Pr oject Wil d. 1,985,Westem Regional Environmental Education Council.
San FranciscoBay National Wildlife Refuge,SaltMarshMnnual,an educatlr'sguide.1990,U.S. Fish &
Wildlife Service.
WetlandsCurrianlum. 1990,SantaClara Audubon Society.
SqnFranciscoBay Seasonal
Smith, A. ,ed. Child Ecology,Grade3. TheBayandMarsh.1974,Chlld Ecology Ptess, Los Altos,
California.
Storer,John.Webof Life 1956,National AmericanLibrary, New York, N.Y'
BAYRESOURCES
SAN FRANCISCO
Bair Island
Eastof BayshoreFreeway(101),next to Redwood Shores- bkd watching and hiking.
Under the protection of P.O.S.Tas of January 1997, this largest expanseof restorable
wetland needspublic support and funds to completethe purchase'
Bayfront Park
Bayfront Expressway,Menlo Park - bird watching, hiking.
Burlingame Shorebird Sanctuary
BayshoreHighway, Burlingame -bird watching.
Candlestick Point
Gilman Ave., San Francisco (415) 822-9266 -brdwatching,
fishing, hiking, picnicking.
Coyote Creek Lagoon
Fremont Blvd., South of Cushing Parkway, Fremont - bfud watching, fishing, hiking,
picnicking, nafute center, boatlanding, restrooms'
SAN FRANCISCO BAY RESOURCES
Coyote Point Park
Coyote Point Drive, Burlingame (650)573-2592- bird watching, fishing, hiking,
picnicking, nature center,boatlanding, restrooms.
Don Edwards San FranciscoBay National Wildlife Refuge Environment Education Center
Grand Blvd., Alviso (408) 262-5513- bird watching, hiki.g picnicking, nature center,
restrooms.
Environmental Volunteers
3921East BayshoreRd., Palo Alto, CA 94303(650) 424-8035- natural science
educationalprograms and field trips for children gradesK - 8.
Golden Gate National RecreationArea
Fort Baker, Marina, Fort Mason, Aquatic Park, San Francisco - bird watching, fishing,
hiking, picnicking area,resfrooms.
Marine ScienceInstitute
1200ChesapeakeDr., Redwood City, CA 94063-7142(650)364-2760- bay discovery
education programs for children.
Mountain View Shoreline Park
Stierlin Road, Mountain View (650)903-6392- bird watching, hiking, picnicking.
Oyster Point Park
Oyster Point Blvd., South San Francisco- bird watching, fishing, hiking, picnicking, boat
landing, restrooms.
Palo Alto Baylands Park
Embarcadero Road, Palo Alto (650) 329-2505- bird watching, fishing, hiking,
picnicking,nafule center,boatlanding,restrooms.
Palo Alto Junior Museum
1451Middlefield Rd., Palo Alto, CA 94301(650)329-2111-natural scienceeducation
servicesfor Palo Alto area.
Peninsula Conservation Center
3921.East Bayshore Rd., Palo Alto, CA 94303(650) 494-9301- environmental library.
Port of Redwood City
ChesapeakeDrive, Redwood City - bird watching, hiking.
San FranciscoBay National Wildlife Refuge Visitor Center
Marshlands Road, Fremont (510)792-4275 - bn d watching, fishing, hiking, picnicking,
nature center,boatlanding, restrooms.
page24
Bay Guide
SAN FRANCISCOBAY RESOURCES
San Mateo County Shoreline Trail
San Mateo, FosterCity - bird watching, fishing, hiking, picnicking'
Sierra Point
Sierra Point, Brisbane-bfud watching, fishing, hiking, picnicking.
Sunnyvale Baylands Park
Sunnyvale - bird watching, hiking, picnicking, boatlanding, restrooms.
Youth ScienceInstitute
16260Alum Rock Ave., San Jose,CA 95127(408)258-4322- scienceeducation
programs for children of all ages.
BIBLIOGRAPHY
1. An Introductionto theEcologyof SanFranciscoEstwry.1990, SaveSan FranciscoBay
Association,Oakland, California
2. palo Alto BaylandsHandbook.7975znd edition, The Leagueof Women Voters of Palo Alto,
Palo Alto, California
SanFranciscoBny.7984,
on theenuironmtntand resources.of
3. Tfu ChangingBay:reaiewm.aterials
Califomia
Francisco,
San
Bay
Chapter,
Francisco
OceanicSod"ty"- San
5. BaylandsSiteGuide.1989,EnvironmentalVolunteers,Ltc., Palo Alto, Califomia
guide.1990San FranciscoBay National WildliJe Refuge,U.S.
6. SaltMarsh Manual,an educator's
Alviso,
Califomia
Fish and Wildlife Service,
3rd ed., San FranciscoBay Wildlife Society
T. Conradson,Diane. ExploringOur Baylands.7995
8. Hunt, Murray. Salt marsh map, figure#3,199I, EnvironmentalVolunteers,Palo Alto, Califomia.