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Did You Know...?

NAS - Nonindigenous Aquatic Species
Mollusks (Phylum Mollusca) are found in marine, brackish, and fresh waters. They include a diverse group of animals such as clams, mussels, oysters, scallops, abalone, conchs, shipworms, snails, nudibranchs, chitons, squids, and octopuses. The most notable nonindigenous mussel introduction is the zebra mussel (Dreissena polymorpha), a native of eastern Europe.

Ecosystems

Many places on Earth harbor life, but the conditions that shape these environments—weather, climate, and even the organisms themselves—are widely varying, resulting in the amazingly diverse landscape of the Nation that includes caves, forests, coastlines, and deserts. The Status and Trends of Biological Resources Program studies the diverse terrestrial and aquatic ecosystems of the Nation to better understand where, how, and why the Nation's habitats change overtime.