Pelicans and Other Colonial Nesting Birds
Because American White Pelicans ( Pelecanus erythrorhynchos) and other colonial waterbirds concentrate their nesting activities at a few sites, these species are highly vulnerable to diseases, predation, weather events, collisions with nearby structures, and other disturbances. At the turn of the twentieth century, colonial waterbirds played an important role in the conservation of birds in the United States. This early conservation movement inspired the creation of refuges and conservation laws to protect nesting colonies in the northern Great Plains and throughout the nation. For example, President Theodore Roosevelt issued an executive order in 1908 designating Chase Lake and surrounding habitats in south-central North Dakota as a National Wildlife Refuge, primarily to protect a persecuted nesting colony of American White Pelicans. This nesting colony would eventually grow to support one of the largest American White Pelican colonies in North America, in addition to thousands of nesting cormorants, gulls, herons, egrets, ibises, and terns. Many states in the U.S. have identified information on colonial waterbird distribution and populations as a conservation priority. In part, this concern reflects declining populations for some species or, conversely, reflects increasing populations that escalate conflicts at landfills, aquaculture facilities, cropland, recreation sites, and urban areas. Sustained productivity from waterbird colonies in the northern Great Plains is important to the health of these species. Currently, researchers at Northern Prairie Wildlife Research Center, in cooperation with the U.S. Fish and Wildlife Service, are identifying factors (e.g., climate, disease) that potentially limit reproductive success and recruitment of pelicans at Chase Lake and elsewhere in the northern Great Plains, and are developing improved methods to estimate nest numbers and monitor productivity of pelicans and other nesting waterbirds.