Salt Marsh Ecology

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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

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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

Spartina alternifloraSpartina patens

Salicornia (pickleweed)

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

Salt Marsh at LOW Tide

You can see the water line, where the water usually comes up to at high tide!

Exposed muddy bottom

Direction of water flow at low tide

Direction of water flow at high tide

OceanLand

• 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

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• 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!

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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?

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• Salt marshes are recognized as important nursery grounds for many commercially and recreationally valuable fish and shellfish species

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

http://www.dep.state.fl.us/COASTAL/images/habitats/seagrasses/Aerial1.jpg

Boats can cause extensive

damage to submerged vegetation

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