Salt marshes are incredible, ever-changing places filled with an amazing diversity of life. Also called coastal and tidal marshes, they are low, coastal grasslands where the continual ebb and flow of the tides create change on a daily basis. High tides fill tidal creeks with salt water and bring fish such as flounder and mullet with them. Low tides expose mud flats and creek banks, attracting birds to feast on the burrowing creatures that make the mud their home.
Salt kills most types of plants so those that live in a salt marsh need to be different. Eelgrass, pickleweed, cordgrass, saltworts, and rushes all are tolerant of salt water and thrive under conditions that would kill other plants.
These plants also have different levels of salt tolerance. Those that are more salt tolerant, live in the lower sections of a salt marsh, where tides can flood them twice a day. The less salt tolerant plants live in the high salt marsh, where salt water will reach them only during really high tides.
The diversity of animal life in a salt marsh is amazing. Tiny shrimp, worms, crustaceans, and crabs live in the mud. Eels and fish swim in the tidal canals and their babies take refuge in the tangles of roots and plants.
The rare American crocodile and the American alligator often make their home in salt marshes. Two other reptiles, the salt marsh snake and the diamondback terrapin, can only be found in salt marshes.
River otters, raccoons, muskrats, bobcats, foxes, coyotes are among the mammals known to visit. The marsh rabbit and the endangered salt marsh harvest mouse are specially adapted to salt marsh life. The gentle manatee also makes its home in the deeper tidal canals of the salt marsh.
Birds bring the greatest variety to salt marshes. Though only a few species live year round, hundreds of species visit salt marshes each year to rest, eat, and nest. Ducks dive for fish and dabble for vegetation in the tidal creeks. Herons, bitterns, and egrets prowl the banks for fish, crabs, and other small critters. Rails, sandpipers, and stilts probe the mud for crustaceans and worms, while spoonbills and avocets sweep the water in search of small aquatic animals. Sparrows, wrens, and warblers pluck seeds and insects from the grasses and other plants. Osprey and even Bald Eagles swoop down to catch fish with their strong and sharp talons.
As noted above, salt marshes provide important habitat for a multitude of species, from tiny crustaceans, to birds, and to large mammals and reptiles. Importantly, they also protect coastlines from natural disasters such as super-storms, hurricanes, and tsunamis. Looking forward, salt marshes may also play a helpful role in slowing climate change, as they can effectively absorb the greenhouse gases that may cause the global temperature to rise.
Sadly, many of America’s salt marshes have already been lost to development. Those that remain face threats from pollution and more development, though many states now have laws protecting these marshes.
Salt marshes are found along the Gulf, Atlantic and Pacific coasts in sheltered areas protected from pounding surf.
Best Time to Visit
During the spring when migration is in full swing and in the summer.