Salt marshes also produce abundant nutrients through decomposition, provide food and cover for marine and terrestrial animals, and serve as a natural water purification system. Mudflats, which may look barren on first glance, abound with animal life just below the surface. Huge concentrations of worms, clams, molluscs, crustaceans and migrating shorebirds depend on healthy mudflats to survive. Sandy beaches, rocky intertidal and nearshore subtidal zones, and islands also play an important role in sustaining the natural environment. Intertidal and nearshore subtidal habitats support marine algae which provide home for a broad array of organisms, including scallops, flounder, urchins, lobster and waterfowl.
Islands provide critical habitat for seals, nesting seabirds and unique plant communities.
Many who live on the shores of the Gulf of Maine appreciate its biological wealth and have nourished themselves from its bounty. However, habitat loss, wetland and associated upland loss, overharvesting, oil spills, pollution and other cumulative effects of development threaten the integrity of the Gulf ecosystem. Nationwide, the Service manages over 500 National Wildlife Refuges, an outstanding network of lands dedicated to protecting wildlife. The Service also operates National Fish Hatcheries, raising and stocking about 200 million native fish annually. Through its Ecological Services program, the Service also safeguards endangered species, resolves fish and wildlife issues related to hydropower projects, curbs toxic contamination and restores and protects valuable fish and wildlife habitat on public and private lands through partnerships.