Migration Dynamics of the Whooping Crane

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The critical habitat specified above includes approximately 160 square miles (103,000 acres) of land in the centrars and a 54 mile stretch of the 'Big Bend" reach the Platte River in what is commonly referred to a (Figure 1 -1) . The Service's decision tool akecthis reduct on was basthatupon "a more thorough assessment of av ailable b 9 „ 1978 20938). provided by the Nebraska G� anandaParksoCommission, 43in F commenting on the Specifically, the Nebraska G original proposal, suggested that only the Pl atte River channel, I immediately adjacent wetlands, and rainwater determined as critical habitat. wetlands plus their ass containing [Type III wetlands are inland shallow fresh marshes usually to 6 inches or waterlogged soil during the IVwetgandssareoinland deepdfreshpmarshes covered more of water; whereas Type re of water during the growing season (FWS 1971, with 6 inches to 3 feet or mo P 21)]. In its comments, the Nebraska Game and Parks Commission ichkraWnwatedr that sufficient data areal °�nents of theowhoopi ngncranecduri ng migrati on. The basins would meet the decreased its final ruling on the dimensions of Service agreed and accordingly Nebraska's critical habitat zone. 4) clarified, ied, it was possible for the Service As Johnson and Temple (1980, p• and wintering grounds with to del i neate critical ti cal habitat on both the nesting some precision sin whooping ng cranes used these areas every year and study data were readily available. Determinati one °tocinsufficient tainformation etolmakei on route, in contrast, was problematic d desi gnati ons. Johnson and Temple noatldincluded the recommendati recommendations foromegrateon had recognized this deficiency and h studies as part of thei r draft Whooping ofrane Recover 1 Man i ns197 ong that is, the Team had identified several are migration route where many sightings ghti n atte Rivermzoneo nrNebraskar (Johnson 1981, these areas [one of which was the p. 33)] were designated as critical development in before their sof thhecance,to the concern that they might be 1 ost to P As result, the expressed d purpose of studies cr ane s co ul d be determ i ne d". was collect h, ri conducted by Johnson and Temple (1980) und decisions critical biological data necessary to make ecologically habi tat within the whooping migati on corridor. 1.3 SCOPE OF REPORT Johnson and Temple's (1980) studnhsotheragroups d ,� have °substantially igincreased whooping cranes by the Service a the base of informati on on migratory habi tat urati be W hoo iong Cranel prof ectas P flock since 1978. Through the Service s Coo per have been regul arl y i ni ti ated i n 1975, conf i rmed si ghti ngs al ong the flyway tabulated and reported following each birds, the Canadian rWildlife TServi�itate monitoring and tracking of individual year chicks on the nesting grounds in began color-banding all young - 1977; by late 1984, a total of 60 birds rched to the col orl bandsnon• some ofe summer of 1981, radio - transmitters w e atta ear a family group was tracked by aerial the chicks, and in the fall of that y 1 -4