Why is the marsh important for birds?

A marsh is important for any type of animal. It provides a rapid food chain and homes for many birds and other animals to live. Imagine a world where all marshes disappear, insects lose their home and die, the fish can't eat insects so they die, bears or other animals can't eat fish so they die... eventualy we'll die, and so will any other living thing on earth... all because the marshes were gone.