Wetlands are actually unsung heroes. They nurture young fish, provide refuge to birds, bats, bugs, and sometimes to big mammals like panthers and bears. Mangroves, for instance, are trees and shrubs that inhabit coastal swamps, and they form peat that is home to clams, snails, crabs, and shrimp, and filter pollution out of the water. Their “interlaced roots protect tiny fish from ravenous jaws of larger fish, and even manatees and dolphins take refuge there.