Short answers, pulled from the story.
A wetland is an area where the water table stands at or near the land surface for a long enough period each year to support aquatic plants. This definition identifies them as communities composed of hydric soil and hydrophytes that are flooded or saturated in water either permanently or seasonally.
Wetlands exist on every continent except Antarctica according to global distribution data. They can be found in freshwater, brackish, or saltwater environments ranging from the Arctic to tropical zones like the Gulf of Mexico.
Seventy-five percent of United States commercial fish and shellfish stocks depend solely on estuaries to survive. Amphibians such as frogs and salamanders need both terrestrial and aquatic habitats to reproduce while reptiles including alligators and crocodiles inhabit specific regional wetlands.
Sixty-five to seventy percent of the world's wetlands have been lost since 1900 due to human disturbance and degradation. Wetlands face more environmental degradation than any other ecosystem on Earth according to the Millennium Ecosystem Assessment from 2005.
Work under an international treaty seeking to identify and protect wetlands of international importance began in 1971. The Ramsar Convention aims to list these areas and promote their wise use through methods that include restricting access and public education.