Wetlands, which include freshwater, brackish, and saltwater marshes, fall into this category, as do rivers, ponds, lakes, open ocean, and beaches. Freshwater wetlands alone have shrunk from more than 200 million acres in 1780 to less than 100 million acres today, primarily because of conversion to agriculture and development. Among the threats to inland and coastal habitats are the draining and diversion of water, loss of water quality, invasive plant species, human disturbance at beaches, and urban encroachment. Seabirds are imperiled by entanglement in driftnets or longlines, over fishing of their food supply, and ocean pollution.
Figure 1. Of the 268 water and wetland bird species, 212 are green species, 31 are yellow WatchList, and 25 are red WatchList.
Figure 2. According to the Breeding Bird Survey (BBS) data from 1966 to 2003, 39 out of 106 water and wetland species are declining, and there is no trend information for 162 species. (The BBS is a roadside survey. Many waterbirds nest far from roads, thus are missed by the BBS.)
Even as other duck species are rebounding, this elegant dabbler has declined by 63 percent, to 7.5 million individuals.
Though its rate of decline is unknown, this bird of western rocky coasts is sensitive to disturbance, and now numbers fewer than 9,000.
There are just over 300 of these rare cranes left in the wild—an improvement over the 15 to 16 individuals alive in 1941.
Additional Yellow WatchList species in water or wetland habitats:
American Black Duck
Additional Red WatchList species in water or wetland habitats:
Nelson's Sharp-tailed Sparrow
Saltmarsh Sharp-tailed Sparrow