Salt Marsh Ecology
http://en.wikipedia.org/wiki/File:Bride-Brook-Salt-Marsh-s.jpg
Salt Marshes: Where land and sea meet
• A salt marsh is a unique environment where
salt water meets the sea
What is a marsh?
• Salt marshes are special because they connect
the land to saltwater bays, oceans, and sounds
• These two environments are very different
from one another and create a very unique
habitat when they come together
Salt marshes: Where land and sea meet
Land
Who lives in a salt marsh?
• Salt marshes are important homes for many
species of birds, fish, shellfish, reptiles and
mammals
Who lives in a salt marsh?
• Salt marshes are especially important for
migrating birds, who find food and shelter in
the marsh
Who lives in a salt marsh?
• Salt marshes are also home to very special
plants which can survive in salt water
What do you think would happen if
you put this plant in saltwater?
The plant would dry out and wilt!
How do plants survive in the marsh?
• Land plants are not used to living in salt water
and will dry out and wilt if you add salt water
• Salt marsh plants have special adaptations for
surviving in salty water
Exposure
to salt
water
Land plant in fresh water
Land plant in salt water
So how do plants survive in the marsh?
• Some salt marsh plants
bleed out excess salt!
• Other salt marsh plants
live farther inland to
limit the amount of
salt water they are
exposed to
http://www.flickr.com/photos/9428166@N03/1332850266
Got Pickle?
• Salicornia, also known as pickleweed is edible
and is named for its salty, pickle-like taste.
• Where does this salt come from? Why the
ocean, of course!
Life in the marsh is harsh!
• Since living in salt water is difficult for most
plant species, only a few species of plants
actually survive in the salt marsh
Smooth cordgrass, Spartina alterniflora
Spartina alterniflora
• Long Island salt marshes are dominated by
smooth cord grass, Spartina alterniflora
• Spartina alterniflora lives directly on the
water, growing out of the muddy bottom
Spartina alterniflora
• Spartina alterniflora sheds excess salt and has
thick, web-like roots to help the plant dig-in
and take in necessary oxygen and nutrients
Why are marshes important?
• The dense roots of Spartina trap sediments
and other particles in the water, building more
marsh!
– Roots also filter out pollutants and excess
nutrients which can otherwise cause harmful algal
blooms
– Spartina also protects the areas behind the marsh
from erosion
Spartina who?
• Spartina alterniflora lives directly on the
water, protecting the plants behind it from the
harsh saltwater environment.
• Behind Spartina alterniflora grows salt marsh
hay or Spartina patens, which is less tolerant
of the salt water environment than S.
alterniflora
Spartina patens (salt marsh hay)
Salt Marsh Zonation
Salicornia (pickleweed)
Spartina patens
Spartina alterniflora
Spartina alterniflora (smooth cord
grass) is always found closer to
water than Spartina patens (salt
marsh hay); this is known as
zonation
Salt Marshes are tidal
• Our oceans, bays and sounds are affected by
the tides
• High tides push water onto land
• Low tides pull water away from land
• Salt marshes are exposed during low tide, and
submerged during high tide
As the earth spins, it moves
into and out of the bulge
created by the gravitation pull
of the moon
You can see the water line, where the
water usually comes up to at high tide!
Salt Marsh at LOW Tide
Exposed
muddy
bottom
Land
Ocean
• At high tide,
water fills the
marsh and
covers much
of the S.
alterniflora
• At low tide,
much of the
S. alterniflora
is exposed
Life in a tidal marsh
http://www.flickr.com/photos/19727876@N00/415368318/
• Submerged Spartina provides important
habitat for fish and shellfish at high tide
Life in a tidal marsh
Glass shrimp (top
left); Sea horse (top
right); Lacuna (bottom
left); Pipefish (bottom
right)
Life in a tidal marsh
• The submerged blades of grass provides
protection
• Protection is a good thing!
http://floridamarine.org/features/category_sub.asp?id=4978
Life in a tidal marsh
http://www.lisrc.uconn.edu/lis_uwtour/grass.asp
Resident and migratory species benefit
from the protection of seagrass beds
Butterfly fish
(left); Lizardfish
(right)
Life in a tidal marsh
• Fiddler crabs hide in their burrows during high
tide and emerge at low tide
Why are marshes important?
• Because of the protection they provide, salt
marshes are important nurseries for many
finfish and shellfish species
– Many of which migrate
out of the area as
adults, but return to
mate and reproduce
Why are marshes important?
• Salt marshes are
recognized as
important nursery
grounds for many
commercially and
recreationally
valuable fish and
shellfish species
http://www.flickr.com/photos/plecojan/455198822/
Why are marshes important?
• In addition to the protection they provide, salt
marsh plants produce incredible amounts of
oxygen
• Salt marshes are as productive as tropical rain
forests!
Why are marshes important?
• Salt marshes are home to the ribbed mussel,
which filters out very fine particles, including
harmful algae such as brown tide
Why are marshes important?
• The loss of salt
marshes is believed
to be a contributing
factor of the
occurrence of
brown tide in Long
Island estuaries
Threats to salt marshes
• Global warming can melt glaciers raising
local sea levels
– Rising sea levels can inundate salt marshes
• Many salt marshes are drained and altered
• ~60% of all salt
marshes in the U.S.
are developed
Threats to salt marshes
Boats can cause
extensive
damage to
submerged
vegetation
http://www.dep.state.fl.us/COASTAL/images/habitats/seagrasses/Aerial1.jpg
Threats to salt marshes
• Invasive species, such as the plant Phragmites,
can displace native plant species, such as
Spartina and change the type of animals that
are normally found there
– Phragmites came over from
Asia; an entire strand may be
just one individual plant!
How you can help
• Learn how salt
marshes are
important, and
tell others!
• Participate in
beach clean-ups