WSP00190 - Laserfiche WebLink

Home Browse Search

. . ,I I I I I I I I I '1 SECnONTHREE Whooping Crane less than 500 feet as well (FWS 1981). Areas which are unsuitable for sandhill cranes also are unsuitable for whooping cranes. Many river reaches with greater vegetative encroachment are no longer suitable for either sandhill crane or whooping crane habitat. Small segments of river that retain wide channels, and segments that have been mechanically cleared and maintained free of vegetation by the National Audubon Society and Platte River Whooping Crane Habitat Maintenance Trust, are the primary suitable whooping crane habitat remaining on the Platte River. 3.4.4 Relation of the Platte River to the Rainwater Basin According to the Kingsley Dam Biological Opinion (FWS 1997), decreased use by whooping cranes of the Platte River in recent times and associated use of the Rainwater Basin area in south- central Nebraska is of serious concern. With over 90 percent of the Rainwater Basin wetland habitat destroyed, waterfowl and crane populations are concentrated into the relatively small habitat base that remains, increasing the potential for disease outbreaks. Major avian disease outbreaks have occurred in recent years in south-centtal Nebraska. Whooping cranes have been reported in several Rainwater Basin wetlands where large waterfowl die-offs from avian cholera have been recorded. As discussed in Section 3.2, avian cholera has been confirmed in wild whooping cranes. Three times, all in the spring, in the last 19 years (spring 1975, 1979, and 1984), a total of 15 whooping cranes had to be hazed away from wetlands where avian cholera outbreaks were occurring. On one of these occasions, seven whooping cranes settled on the Platte River. The FWS (1981) concluded that the disease problem will persist in the Rainwater Basin area, underscoring the need to provide adequate habitat along the Platte River that minim;7p.~ whooping crane exposure to avian cholera Disease transmission may be prevented if Platte River flow is sufficient to ensure a high rate of flushing and dilution and a low density of birds per acre of water. Concurrent with the threat to whooping crane habitat on the Plane River, the disease situation is being exacerbated by continuing losses of wetlands in the Rainwater Basin area 3.5 RECOVERY GOALS The long-term objective of the Whooping Crane Recovery Plan (FWS 1994) is to downlist the status of the species from endangered to threatened by increasing the wild population to 90 nesting pairs in tluee separate populations by the year 2020. The minimum requirements for downlisting are maintenance of the Aransas- Wood Buffalo population (A WP) above the current 40 nesting pairs, and establishment of at least two additional, separate, and self-sust~in;ng populations, each consisting of25 nesting pairs. The growth of the A WP will be expapded to 1,000 individuals. These goals should be attained for 10 consecutive years before downIisting. In order to attain reintroduction goals, there should be about 40 captive breeding pairs by the year 2000. In order to meet these goals, the plan prescribes specific actions under four categories. 3-10 _._ 6I2Il.....'52....)<JRSG'M:FS12 _1JteiDtIr WlMo-d t:IJrIe FefIenII Sef..