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Williams and Dodd In 1968, the California Department of Fish and Game coordinated efforts of private or- ganizations, the Los Angeles Water Department (Los Angeles requires part of the water supply from the Owens Valley), and Federal agencies in the establishment of the Owens Valley Native Fish Sanctuary in Fish Slough. After renovation of portions of the wetland to a safe and stable condition, native fishes were reintroduced (Miller and Pfister, 1971). This type of cooperative action is essential if many endangered wetland-dependent species are to survive. Scarcity of water throughout the grid Southwest has focused attention on wetlands as sources of water to fulfill human needs, usually for irrigation or for livestock. Abuse of wetlands has created problems for resident herpetofauna. For instance, marshes are ditched and channelized, thus exposing tadpoles to predation. Cattle trample both toads and tadpoles. As a result, species such as the black toad, Bufo exsul, and Amargosa toad, B. boreas nelsoni, both restricted to very small marshlands in California and Nevada, re- spectively, face an uncertain future (Busack and Bury, 1975). EXAMPLE OF THE WHOOPING CRANE One of the best known endangered birds and perhaps the best example of an endan- gered species' dependence on a variety of wetland habitats is the whooping crane, Gros arnericana. The population at Aransas National Wildlife Refuge reached aloes 13 adults and 2 young - in 1941. Current estimate of remaining wild cranes in the Canadian flock is approximately 75 birds. Prior to human interference, the whooping crane population was estimated at 1,300 to 1,400 birds. Its endangered status and biology have been docu- mented by Allen (1952, 1957). The whooping crane's life cycle encompasses a distance of approximately 4,200 km between the Northwest Territories of Canada and the Aransas National Wildlife Refuge on the Texas coast. In April, whoopers leave the Aransas Refuge, migrating northward along the Central Flyway, arriving at their traditional. breed- ing grounds in Wood Buffalo National Park in the Northwest Territories by late April or early May. Cranes build their nests in wetland areas in water 0.3 to 0.6 m deep and re- main in the area during spring and summer months. The last known whooping crane nest in the United States was observed in 1889 (Miller, et al., 1974). In October, adult and young whooping cranes begin the migratory flight to the Texas Gulf coast passing through southern Canada, northeast Montana, North Dakota, South Dakota, Nebraska, Kansas, Oklahoma, and Texas. Along the path, riverine wetlands are essential for feeding and resting. Cranes feed on aquatic plants and animals in marshes and use wet meadow areas and islands along braided river channels as roosting areas. Along the migratory route, most of the crane's critical habitat areas, identified by the LJ.S. Fish and Wildlife Service, are wetlands located along stream bottoms and reservoirs (Sheppard, 1978a, 1978b). Whooping cranes spend the winter in tidal marshes along the Texas coast. Upon arrival, pairs and families of cranes establish feeding and roosting territories. Salt and fresh water marshes provide for the crane,~t„an abundance of food organisms -blue and fiddler crabs, clams, shrimp, and crayfish. Decline of the whooping crane population resulted from illegal shooting and destruction of wetlands. Wildlife laws enacted during the early 1900's virtually eliminated illegal shooting, but unfortunately did nothing to prevent continuing destruction of the cranes' wetland habitat. 572