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I I I I I I I I I I I I I I I I I ry}~g~8 SECTION THREE Whooping Crane 3.1 HISTORY The whooping crane (Grus americana) is the rarest of the world's 15 species of cranes (Meine and Archibald 1996). It was listed as a federally endangered species on March II, 1967, and critical habitat was designated on May 15, 1978. The principal historic breeding range of the whooping crane extended from central Illinois northwestward through northern Iowa, western Minnesota, northeastern North Dakota, southern Manitoba and Saskatchewan, and the general vicinity of Edrnonton, Alberta, to the present nesting area of Wood Buffalo National Park (Wood Buffalo), Northwest Territories in Canada (fWS 1994). Winter distribution was primarily along the Gulf of Mexico from Louisiana to northeastern Mexico. There were several migration routes, including a lesser migration route that crossed the Appalachian Mountains to wintering areas along the Atlantic Coast. Some whooping cranes were believed to have migrated to interior Mexico, following the migration route of sandhill cranes. A non-migratory population occurred in southwestern Louisiana. Allen (1952) estimated that the whooping crane population in "...1860, or possibly 1870, totaled between 1,300 to 1,400 individuals." Banks (1978) used two independent techniques to derive population estimates of 500 to 700 whooping cranes present in 1870. Habitat loss throughout most of its former breeding range in central North America contributed to population declines. One non-migratory population of whooping cranes in southwest Louisiana was decimated by a hurricane in 1940 and later became extinct. By 1941, the migratory population reached a low of 16 individuals with 6-8 breeding birds. Legal protection was obtained, and habitat acquisitions and intensive management instituted for important wintering, breeding, and migrational habitats. Numbers of the wild population increased from less than 30 in the 19405 to 187 in the winter of 1997-1998 (Table 3-1). The only remaining, naturaIlyreproducing, and self-sustaining population occupies single nesting and breeding areas, which are linked by a relatively narrow migrational corridor (Figure 3-1). This population nests in Wood Buffalo and winters on and near the Aransas National Wildlife Refuge (Aransas) along the Texas coast (Aransas-Wood Buffalo population). It migrates through Nebraska twice each year. A 20-year-long interagency experiment to establish a whooping crane population wilhin tile intermountain region of the Rocky Mountains has been abandoned. This involved transplanting eggs from whooping crane nests to be hatched and cross-fostered by sandhill cranes. Lack of whooping crane reproduction and high mortality rates led to discontinuance of the experiment. A second experimental effort to establish a nonmigratory wild breeding population was initiated at Kissimntinee Prairie in Florida in 1993 and consisted of 52 birds in 1996. 3.2 REASONS FOR DECLINE The whooping crane became endangered as a result ofhurnan activities that adversely altered or destroyed whooping crane habitat and shooting. The primary factors involved were loss of nesting habitat in the northern Great Plains of the United States and prairie provinces of Canada due to expanding human settlement agricultural development; loss of wintering habitat due to agricultural expansion; and increased hazards of migration as a result of human development /IllS IITriD6 ~ ctrIIe (eIIIRI Senfces BaFOIl97Z"""'n._ ll/2I1999(~.52 AM)/\JRSGWCFS12 3-1