Rich land habitats saturated by surface or ground water, often abundant in plant and animal life. Marshes or swamps, shallow lakes, coasts, estuaries and flood plains are examples of wetland habitats. These ecosystems are crucial for millions of migratory birds, fish, amphibians, insects, plants and trees. In every country and climatic zone, from the polar regions to the tropics, wetlands provide the basis for human survival and development. Despite their value to the earth’s environmental health, wetlands are the most highly threatened ecosystems on the planet.