My Favorite Marsh
Teachers’ Pre-Visit Packet
The staff at Crissy Field Center is pleased that your class will be participating in My
Favorite Marsh, an urban environmental education program. This packet contains
logistical information about your program as well as resources for you and your
students. Among these resources are activities that you may find useful in preparing
your class for their visit and follow-up activities for use after the program. Please feel
free to use only the activities you feel are most appropriate and convenient for your
class and curriculum schedule.
Thank you again for participating in our education programs, and we look forward to
seeing you and working with your class!
What is a Marsh?
A marsh is one type of wetland. Wetlands are areas of land that are covered by fresh or
saltwater all or part of the year. Marshes, swamps, bogs, and fens are all different types
of wetlands.
Marshes are areas of soft, wet, low-lying land, characterized by grassy vegetation and
often forming a transition zone between water and land. The word “marsh” has different
meanings for different people. If you live near the ocean, this term might bring to mind
images of salt marshes or brackish tidal marshes. Perhaps freshwater systems come to
mind with cattails filling in old oxbow lakes. If you are from Minnesota or the Dakotas,
you may think of prairie potholes. The Crissy Field marsh is a tidal saltwater marsh.
Despite their diversity, all marshes have two things in common:
 All marshes contain vegetation that is not woody.
 Marshes tend to develop in zones progressing from terrestrial habitat to open water.
From “Wetland Glossary” http://vathena.arc.nasa.gov/curric/land/wetland/gloss.html
Table of Contents
What to Expect .......................................................................................... 4
A summary of the logistics and expectations for the day.
Schedule for the Day ................................................................................ 5
Approximate times for your program activities.
Resources for Teachers .......................................................................... 7
Background information ....................................................................... 9
General information about wetland ecology and facts about wetlands
in the Bay Area.
Vocabulary ........................................................................................ 10
Vocabulary words printed in bold will be used during your program.
Activity 1: Setting the Stage ................................................................ 11
Some questions to help your students start thinking more deeply
about marshes and wetlands.
Activity 2: What’s in a Word? .............................................................. 12
A mnemonic device to give your students a framework for the things
they’ll see when they visit the Crissy Field marsh.
Activity 3: Web of Life......................................................................... 13
A hands-on activity about food webs and ecosystems which can be
used before or after your visit to Crissy Field.
Activity 4: Migration Fun ..................................................................... 15
An active game that stresses the importance of marshes as resting
places for migrating birds.
Activity 5: Create a Critter ................................................................... 16
An art activity that might be used after students have experienced the
marsh environment and know about some of the animals that live at
the Crissy Field marsh.
Resources for Students ......................................................................... 17
Wetland Facts .................................................................................... 19
A fun fact sheet about wetlands with a focus on the Bay Area.
Bay Area Marsh Plants and Animals..................................................... 20
An illustrated guide to some of the common plants and animals that
can be found in Bay Area wetlands.
Marsh Word Search ............................................................................ 25
A word search (and answer key) using vocabulary related to My
Favorite Marsh.
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What To Expect…
This program includes indoor and outdoor components. First, your students will discover
the importance of wetlands while working with marsh models. Then they will go outside
with digital cameras for a game of “Marsh Bingo” around the Crissy Field marsh. After a
short lunch break, they will investigate marsh mud under microscopes and create a
marsh animal mask and collage. Please ask students to dress appropriately for walking
outdoors and getting messy and to be prepared for all kinds of weather.
 Arrival
Staff from the Crissy Field Center will greet you at the entrance. We will
happily provide nametags for your students, but you can save time by giving
them nametags before you arrive. Your students will have the chance to use
the restrooms and put away their lunches and backpacks before the program
begins.
 Lunch
Please have your students bring a bag lunch. There will be a scheduled lunch
break during which your class will eat outside in the garden in back of the
Center. If it is raining or cold, we will provide an indoor space for your lunch.
 Chaperones
The active assistance of adult chaperones can help to make your program
even more successful. We will ask chaperones to spread themselves out
among the students to help answer questions, distribute supplies, and
manage safety (particularly when crossing the street).
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Program Schedule – all times are approximate
Total Program Time: 3 hours
Arrive and settle in: 5 minutes
Students will have the chance to take a bathroom break and will receive nametags
for the day. We will provide a place to store lunches, backpacks, jackets, and other
items.
Welcome and introduction: 15 minutes
Students are introduced to the park and to the definition of wetlands.
The importance of marshes: 25 minutes
Working in small groups, students perform experiments with marsh models.
Marsh bingo: 60 minutes
In the same small groups, students use digital cameras while they explore the Crissy
Field marsh.
Lunch: 25 minutes
Students should bring a bag lunch. Unless it is raining, your class will eat outside.
Mud investigation: 25 minutes
Students use microscopes to examine and identify critters that live in marsh mud.
Mask making: 20 minutes
Students make a double-sided mask to take home; one side is a drawing of their
favorite marsh animal and the other side is a collage of their photos of the Crissy
Field marsh area.
Closing: 5 minutes
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Resources
For Teachers
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Background Information about Marshes and Wetlands
Wetlands are areas of land that are wet all or most of the time. They often form a transition zone
between dry land and open water. This “blending” of habitats, combined with the presence of
moving water and nutrient-rich mud or silt, helps make wetlands some of the most productive
ecosystems on earth.
Wetlands provide a variety of benefits. Many wetland plants are able to absorb and filter
pollution from the air and water. Their spongy soils can hold vast amounts of water which is then
gradually released into underground aquifers; this helps reduce flooding and maintain
groundwater supplies. Wetlands also provide a safe place for birds and other animals to live, take
refuge, and raise young.
Tidal Salt Marsh Ecosystems
Tidal salt marshes usually form in the zone between the highest tide and the mean tide levels.
These marshes are subject to flooding by the high tides that occur twice each day. They are noted
for the abundant plant life which grows in their salty, waterlogged soil. Most plants cannot grow
in salty soils because the salt will literally suck fresh water out of the plants. However, some
plants have adapted to a salt life; these plants are called halophytes, meaning salt-loving. They
either excrete the salt through special cells or are able to keep salt out of their root systems. In
the marsh, these plants are also adapted to being submerged by tidal waters part of the time.
Salt marsh plants grow in distinct zones. Each zone is dominated by a particular plant species.
The distribution of each species is determined primarily by the amount of time it can be
submerged. The amount of salt in the soil and the water also determines plant distribution.
Eighty-five percent of the salt marshes around the San Francisco Bay have been destroyed; salt
ponds, housing developments, roads, landfills, airports, and other structures have been built on
top of them, resulting in loss of habitat for salt marsh plants and animals.
Adapted from Salt Marsh Manual, Amy Hutzel, Fran McTamaney and Sandy Spakoff, U.S. Dept. of the Interior Fish
and Wildlife Service, Don Edwards San Francisco Bay National Wildlife Refuge, Fremont, 1996.
Tidal Marshes…
 Provide breeding grounds, resting areas, and habitat for a variety of wildlife and plants.
 Help filter out pollution and other impurities in the air and water.
 Prevent and reduce flooding by absorbing water.
 Provide vital food for small invertebrates, which are then eaten by larger invertebrates, which
provide food for birds and fish, which humans may eat.
 Are used by a wide variety of bird species at some time in their lives.
 Are home to at least 50% of California’s threatened or endangered animal species.
 Are used for hunting, fishing, bird watching, and other recreational and educational purposes.
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Vocabulary
decay:
to rot, decompose, or break down
ecosystem:
all the living organisms that are interdependent on one another,
plus their environment
habitat:
the place where a plant, animal, or person lives and finds what it
needs to survive
interdependence: needing or relying on one another for survival
marsh:
a type of wetland; marshes are one of the most productive
ecosystems on earth and are home to a wealth of plants and
animals
pesticide:
a chemical used to kill insects
pollution:
something that makes the environment dirty or unsafe
shellfish:
crabs, clams, mussels, crayfish and other water animals that have
shells
tide:
the rise and fall of water along the coast
wetland:
an area of land that is wet all or most of the time, found between
dry land and open water, usually with its own kinds of plants and
animals; marshes, swamps, and bogs are examples of wetlands
adaptation:
physical or behavioral changes or features that help an animal to
survive in its particular habitat
consumers:
organisms that eat producers or other consumers
decomposers:
organisms that eat and break down dead things or waste products
food web:
the way in which all living things are connected by what they eat,
and what eats them
migration:
travel over long distance
producers:
organisms that make their own food or energy (such as plants)
survive:
to continue living
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Activity #1: Setting the Stage
You may wish to discuss the following questions with your students:
 What do you know about tidal marshes?
 Is there water in a tidal marsh?
 Where does the water come from? Is it salty or fresh?
 Are there plants in a marsh? Around a marsh?
 What kinds of plants grow in a tidal marsh?
 What kinds of animals live in and around a tidal marsh?
 Do people live there? Do people visit there?
 What do people do when they visit?
Encourage your students to generate 2-3 additional questions of their own. If you like, you can
bring them with you on your program and ask us!
Adapted from Marsh Mania! National Aquarium in Baltimore: www.aqua.org/education/teachers/marsh.html
Alternatives for Setting the Stage
Try these activities with more advanced students, students that are visual learners, or to engage
your class in more creative discussions about marshes.
 Divide students into small groups. Provide each group with a large piece of paper or
space on the board and ask them to write down anything they know about marshes (or
words/phrases that come to mind when they think about marshes). Then have each group
circle the 5-6 things they think are most important. Have each group put on a skit in
which they act out these 5-6 things.
 Divide students into small groups and provide each group with a large piece of paper and
craft supplies such as cotton balls, aluminum foil, string, etc. On the paper, have the
students draw or create their vision of a marsh. Ask the groups to share their creations
with the class. Predict which elements they might actually see at Crissy Field. Revisit the
posters after your program and have students add or remove things from their posters to
make them reflect what they actually saw at the Crissy Field marsh.
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Activity #2: What’s in a word?
This simple mnemonic device will help give your students a framework to think about the kinds
of things they may see when they visit the Crissy Field marsh. You may want to remind your
students that, although the Crissy Field marsh contains saltwater, other marshes contain only
fresh water.
Mud
Animals
Reeds
Salt and Sand
Homes
Once your students have some information about marshes -- possibly after their program -- have
them come up with mnemonics of their own. They may also wish to make drawings to go with
their mnemonics.
Adapted from a lesson by Michele Sullivan, Cabrillo School, Pacifica, California.
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Activity #3: Web of Life
Materials:



Ball of yarn or string
Scissors
Masking tape or cards with the elements of the Crissy Field marsh and dune system (from the
following page) written on them. If using cards attach yarn or string to them so the students
can wear them around their necks. You will need enough tape/cards so that each student can
have a different element.
Procedure:
1. Give each student a piece of tape or a card with one of the elements written on it.
2. Have the students form a circle.
3. Hand one student the ball of yarn. The student will hold onto one end of the yarn while
tossing the ball to another student who has an element on which his/her element is dependent.
As the student tosses the yarn, s/he should articulate the dependency. For example, “I am the
Great Blue Heron and I depend on the Pacific Sardine for food.”
4. When the ball has been tossed to all the students, each student should be holding onto a piece
of the yarn. The result will be a web of life created with the yarn and the students.
5. Ask the students what would happen if one of the elements became extinct or could no longer
survive in the area. With the scissors, cut the yarn leading to and from the student with the
extinct element. Are other elements affected? What would happen if something else were no
longer present in the ecosystem? Again cut the yarn leading to and from the student with that
element card. Continue until it is clear that the web of life will not function properly unless
all the elements are present and healthy.
Discussion:
In an ecosystem, such as a marsh, all the elements are interdependent. The animals cannot
survive without the plants; the plants cannot survive without the sun and water. Together, all the
elements make a web of life. If any of the elements are damaged or disappear, the entire
ecosystem is affected.
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Elements of the Crissy Field Marsh and Dune System
Birds (Consumers)
Crustaceans (Consumers)
Great Blue Heron
Long-billed Curlew
Willet
Great White Egret
Snowy Egret
Cormorant
Seagull
Brown Pelican
Black Phoebe
Killdeer
Kingfisher
Purple Shore Crab
Mud Crab
Dungeness Crab
Fiddler Crab
Striped Shore Crab
Fish (Consumers)
Mud Critters (Decomposers)
Pacific Sardine
Shiner Surf Perch
Three-Spined Stickleback
Bay Pipefish
Top Smelt
Copepod
California Horn Snail
Flat Worm
Amphipod
Mammals (Consumers)
Bacteria
Phytoplankton
Zooplankton
Mud Critters (Consumers)
Gem Clam
Bent-nose clam
Skeleton Shrimp
Microscopic Life
Red Fox
Raccoon
Gopher
Field Mouse
Human
Coyote
Marsh Plants (Producers)
Pickleweed
Salt Grass
Eelgrass
Abiotic (non-living) Elements
Dune Plants (Producers)
Water
Oxygen
Sun
Wind
Mud
Sand Dunes
Purple Bush Lupine
Sticky Monkey Flower
California Poppy
Coyote Brush
Beach Strawberry
Live Forever
Note: Illustrations of many of these elements are included on pages 20-24 of this
packet.
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Activity #4: Migration Fun
Materials:


16-24 handkerchiefs or scarves (two handkerchiefs or scarves for every three students)
Large open space
Background:
Many birds migrate very long distances each year. Just like humans, birds need “rest stops”
when they travel. They need places where they can find healthy food, water, and safe spots to
sleep. Marshes are the “rest stops” for shorebirds as they migrate. When humans fill in marshes
and other wetlands to build homes and businesses, shorebirds have an increasingly difficult time
with their annual migrations.
Procedure:
1. Take your students out to the playground or another area where there is a large open space.
2. Discuss with your students why birds migrate each year. Explain that birds need marshes and
other wetlands to help them with their migrations.
3. Place half the scarves on the ground at one end of the open space and the other half at the
other end. The scarves should be several feet apart.
4. Tell the students that they will be migrating birds. The scarves represent marshes where they
can rest. In order to rest at a marsh a student needs to have at least one foot on a scarf. Each
“marsh” can accommodate no more than 3 students at a time.
5. All the students should begin at one end of the field “resting” at one of the “marshes.”
6. When you say “migrate” all the students should make their way to the other end of the field
and find a “marsh.”
7. Before announcing the next “migration,” tell the students that a new neighborhood has been
built. All the houses have been built on top of landfill that replaced some of the marsh areas.
Remove two of the scarves from the end of the field opposite from the students. Have the
students migrate. Any student who does not find a marsh to rest in must go to the sideline.
8. Continue to have the students migrate from side to side, announcing various events that
decrease or increase the marsh areas. Some events that decrease marsh habitat include: an oil
spill; pollution entering a marsh from a nearby city; people using the surrounding area for
recreation and impacting it to the point that birds no longer feel safe; over-fishing in the area.
Marsh habitat may increase when people restore the natural ecosystem of an area.
Adapted from a Headlands Institute Enrichment Seminar activity.
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Activity #5: Create a Critter
You may wish to use this activity after your visit to Crissy Field. Students can use the knowledge
they have gained about the marsh environment to help them build a well-adapted marsh critter.
Materials:



Hard fruits and vegetables to serve as critter parts: for example, potatoes, apples, pears,
carrots, eggplant, celery (you can cut various shapes out of some of the vegetables).
Items to make fur and other features: for example, small flowers, pipe cleaners, and cotton
balls.
Toothpicks to help attach body parts to one another.
Background:
All animals must be well-adapted to their environments. Animals that live in forests often are
good climbers so they can take advantage of the food and shelter in trees. Animals that live in
deserts must have special adaptations to deal with the sun and the dry conditions. Marsh animals
must have special adaptations to survive in the marsh environment.
Procedure:
1. Have students think about what the marsh was like when they visited. What was the weather
like? What food sources were available? What predators were present? What kinds of legs
did the birds have? How does that help them survive in the marsh?
2. Have each student use the materials available to design an animal that would be able to
survive in or near the marsh.
3. After the students have completed their critters, they can make presentations describing their
animals and the animals’ adaptations.
Alternative:
Do this as a drawing activity, rather than creating three-dimensional creatures.
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Resources
For Students
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Wetland Facts
Did you know…?
 The San Francisco Bay Area has the largest network of marshes on the west
coast of North America!
 Over the past 200 years, 90% of the Bay Area’s wetlands have been
destroyed.
 Most birds (almost 75% of all bird species) use wetlands for food, shelter, or
both at some time in their lives.
 95% of all the fish and shellfish we eat in the U.S. depend on wetlands.
 Wetland plants can help clean up water and air pollution by absorbing and
filtering it out.
 Wetlands absorb a lot of water, helping to prevent floods and replenish
groundwater supplies.
 Large parts of San Francisco, Washington D.C. and Boston have been built
on wetlands.
 One of the biggest threats to the San Francisco Bay today is runoff from
cities. Rain and other water that flows through our cities collects pollution -such as paint, grease, fertilizers and pesticides -- which then wash into the
bay.
YOU Can Help!
 Use household and body products (like soap, cleaners, and fertilizer) that are
safe for the environment.
 Keep hazards like paint, soap, oil, and lawn products out of the street, where
they could get into streams, rivers, or wetlands through the storm drains.
 Use your voice – share what you know about wetlands, and speak up about
what’s important to YOU!
Adapted from Aquatic Outreach Institute materials.
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Bay Area Marsh Plants and Animals
AMPHIPOD
(Beach Hopper)
Amphipoda



Has two groups of legs: five pairs
for walking and three pairs for
swimming
Looks flattened from side to side
and can jump a great distance to
escape predators
Found under boards, rocks, debris
and mud at the edge of salt marshes
STRIPED SHORE CRAB
Pachygrapsus crassipes



COMMON GARTER SNAKE
Thamnophis sirtalis



Lives in or around water; forages
on land or in quiet pools
Light-colored longitudinal stripes
Feeds on small fish, amphibians,
and water insects
Found along rocky shore areas in
damp cracks and crevices under
rocks
Named for the green lines on its
back. Very colorful with red and
purple on its legs.
Scavenger that eats decaying plant
and animal matter
VIRGINIA OPPOSSUM
Didelphis virgineaus



16
Scaveger introduced by settlers
from southern United States
Only mammal with prehensile tail
and opposable thumbs
Hides in trees or crevices during the
day
RACOON
Procyon lotor




Leaves hand-like footprints in the
mud and sand along creeks and the
edges of marshes
Nocturnal (active at night)
Finds homes in hollows of trees
Eats berries, acorns, crayfish,
clams, insects, etc.
SALT MARSH HARVEST MOUSE
Reithrodontomys raviventris



PICKLEWEED
Salicornia subterminalis
SALT GRASS
Distichlis spicata




Main food source for the
endangered salt marsh harvest
mouse
Pumps salt crystals up to the tips of
the stems; stores the crystals until
the stem tips drop off
Grows in the middle zone of salt
and brackish water marshes
Endangered species due to loss of
habitat
Found only in saltwater wetlands of
San Francisco Bay and its
tributaries
Feeds on plants found in salt
marshes, mainly pickleweed



17
Found in middle and upper zones of
salt marshes throughout coastal
California
Low growing with stiff, green
leaves
Excretes salt crystals through
special glands in its leaves
Leaves and seeds provide food and
nesting materials for marsh birds
BROWN PELICAN
Pelecanus occidentalis
WILLET
Catoptrophorus semipalmatus



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Have a wing span of up to 6½ feet;
they dive from as high as 30 feet
above the water to catch fish
Social birds that fly in groups and
nest in colonies
Removed from Endangered and
Threatened Species lists as their
populations have increased


KILLDEER
Charadrius vociferous
MALLARD DUCK
Anas platyrhinchos





Most widespread shorebird in
California
Two black stripes on breast
Will feign injury near its nest to
distract intruders
Repeats its name, “kill-deer”
Uses long beak to probe in the mud
for crabs, aquatic insects, marine
worms, mollusks, and small fish
Appears very plain and mudcolored on the ground, but has
distinctive black and white wing
pattern in flight
Some migrate north in the summer
and others remain in the Bay Area
year round



18
California’s most abundant duck;
found in wetlands, estuaries, ponds,
and pastures
Males have metallic green head;
females are speckled brown
Feeds with its head in the water and
its tail in the air
Feeds mainly on grains, seeds and
leaves of aquatic plants but will
also eat some aquatic insects,
tadpoles and small fish
BELTED KINGFISHER
Ceryle alcyon



Common to abundant winter
resident in riparian areas and bodies
of water
Eats mostly fish, also crayfish and
insects in slow moving, shallow
water
Hunts by diving into the water from
a perch or from hovering; noisy,
water-loving bird
GREAT BLUE HERON
Ardea herdias



SNOWY EGRET
Egretta thula
AMERICAN COOT
Fulica Americana





Roosts and nests in large trees
Spends the day in open fields and
marshes
Uses bright yellow feet to scare up
prey (fish, frogs, aquatic insects)
Stabs prey with its slender black
bill
Large expert fisher of creeks and
marshes
Uses bill to capture fish, frogs, and
aquatic insects
Stalks shrews, mice, gophers and
lizards on land



Lives in fresh and saltwater
marshes, wet grasslands, lakes and
fields
Dark gray, duck-like bird
Has long, lobed toes to help swim
and walk over lily pads
Eats a variety of foods including
leaves, seeds, algae, fish, tadpoles,
snails, worms, and aquatic insects
Illustrations courtesy of the Watershed Project and Don Edwards San Francisco Bay National Wildlife Refuge, from
the Watershed Project’s curriculum guide “Kids in Marshes,” 1998.
19
BEACH STRAWBERRY


COYOTE BRUSH
This plant is related to the strawberry
we buy in stores; it makes a similar red,
edible fruit.
The flowers are small and white, and
the dark green leaves grow in sets of 3s.
The plant grows low to the ground.



CHAMISSO LUPINE
(or Silver Bush Lupine)




This shrub has silvery green, palmate
leaves.
Purple-blue flowers grow in spikes.
Lupine is in the same family as peas
and beans but its fruit is poisonous!

YARROW


This is a medium-sized shrub with
small, thick leaves.
Tiny white flowers make clusters of
fuzzy seeds.
This plant is drought-tolerant and fire
resistant.
SEASIDE DAISY
Flowers look like pink or pale purple
daisies with yellow centers.
Rounded green leaves grow mostly at
the base of the plant.
COAST BUCKWHEAT
Yarrow has tiny flowers that grow in
clusters at the top of the plant. The
flowers can be yellow or white.
The leaves are feathery and fern-like.


Grayish-green leaves grow mostly at
the base of the plant.
The clusters of small flowers look like
little white or pink puff-balls on
branching stems.
Illustrations by Katie Clower, Golden Gate National Parks Conservancy.
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