Habitat (natural environment) loss is the number one threat to the survival of many animal species (organisms that share a unique set of characteristics), and water is part of any habitat. Coastal marshes and wetlands in the United States and elsewhere are shrinking every year. Wetlands are areas of land where water covers the surface for at least part of the year and controls the development of soil; marshes are wetlands dominated by grass-like plants. Wetlands in particular support a great variety of bird, fish, and other animal life, and can be used by migrating (periodic traveling) birds as a stop-off point on their long journeys. Without the wetlands, the number of species that can live on the land declines. Habitat loss is primarily caused by human activities, such as logging, development, fishing, and recreation.

Edward Wilson (1929–), a renowned entomologist...