Themes > Science > Earth Sciences > Oceanography > Habitats > Estuaries > Salt Marshes

Salt marshes
form in shallow, quiet water, where the water is salty and still enough for the suspended particles to settle to the bottom. These marshes are some of the most productive lands in the world and produce so many organic nutrients that their influence can be seen far out into the coastal ocean waters. Marshes are based on one plant, the Saltmarsh Cordgrass, which helps stabilize the environment so that many other plants and animals to move in. Other plants including Cordgrass, Saltmeadow Grass, Blackgrass, Bullrush and Sea Lavender add color and variety to the marsh and grow in zones according to their tolerance (or ability to handle the saltiness) of the tidal water. Among the grasses, mats of algae grow in the upper layer of soil. Crabs, snails, insects and muskrats (partially aquatic rodent) are common inhabitants. Snakes and turtles abound, and fiddler crabs pop out of their burrows to find dinner after the tide goes out.

Birds such as the Northern Harrier (marsh hawk) and the marsh hen are also common to salt marshes. Tall, leggy herons and the white snowy egrets wait patiently along the tidal creeks for small fish to swim by. The majestic bald eagle has become much more common in recent years and can often be seen perched at the marsh's edge, or dining on a fish. Marshes are also important stopping-places for migrating birds as well. Every autumn and spring, thousands of ducks and geese find temporary refuge during their travels.

Mangroves
take over from salt marshes in the lower latitudes, filling many of the same functions, although they aren't as productive. The dense and spreading roots of the mangrove trees provide sanctuary for fish, reptiles and insects. Thick foliage gives birds plenty of places to nest or perch while searching the waters below for food. Mangroves also help protect the shorelines from erosion. Beds of Eelgrass are a very important part of the estuarine ecosystem.


Information provided by: http://www.onr.navy.mil