Specific Comments on Platte River Draft EIS

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Migration Dynamics of the Whooping C?rane, With Emphasis on use of the Platte River in Nebraska I Excerpts from EXECUTIVE SUMMARY Flock Size (Section 2.3): Analysis of confirmed an average of approximately 3.2 birds per sightin threesomes have been observed most frequently. ghtings recorded throughout the flyway indicates Whooping cranes migrating singly, in pairs, or in Confirmed sightings in Nebraska from 1940-1 sighting in spring (3.2) and fall (3.1). Overall, rr of the sightings involved 5 birds ar less. reflect a, similar average number of birds per observations were of 2 or 3 birds, and 92 percent Stopover Duration (Section 2.6): Most migrati n stopovers during both fall and spring are of the overnight type where the birds arrive one day an leave the next. They represent brief flight breaks (of about 12 to 16 hours) to rest and feed. Of the 98 stopovers recorded during radio-tracking surveys, 76.5 percent were of this type. In contrast, only 15.3 percent of the stopovers migrations, these longer stopovers occurred most Saskatchewan and northeastern Alberta. ; for 5 days or longer. During both seasonal uently in the relatively remote lakes region of Habitat Use along the Migration Route (Secti n 2.7): Whooping cranes are omnivorous feeders and seen to easily adjust to whatever suitable pl nt and animal foods they encounter at migration stopover locations. Along the Platte River, as well as elsewhere along the flyway, grain fields appear to be used prominently as feeding sites indicatin the species' successful adaptation to cultivated crops (e.g. barley, wheat, corn, milo, and sorg um) which are readily available throughout the migration corridor. Feeding in wetlands typically onsists of foraging in the vicinity of roosts. Migrant whooping cranes are flexible in their sele tion of stopover sites along the flyway and utilize a wide variety of natural and man - developed or odified habitats within the prairie - plains region of the central United States and south central anada. Major prerequisites of suitable stopover locations appear to be the presence of shallow water (standing or flowing) for roosting. Good horizontal and overhead visibility, close proximi y to feeding sites, and reasonable isolation from human developments and/or disturbances. Monitoring of radio-tagged whooping cranes h documentation of each stopover site used by ir during a complete migration. The pattern emergin natural and manmade, are generally selected as roi farm ponds and stockponds of 5 acres or less, and of open water (approximately 105 X 105 feet of : whooping cranes will readily stop at wetlands con site offers the necessary visibility, security, and ac( s, for the first time, permitted the systematic iividual birds (and their traveling companions) ; from available data is that small wetlands, both st sites; e.g., small boreal lakes, "pothole" ponds, flooded grain fields containing as little as 1/4 acre irface area). These findings indicate that migrant aining only a limited amount of open water if the ess to food that the birds require.