Sandhill Cranes Migration
During the spring stopover period, the sand hill crane population occupies about 400 square miles in the Platte and North Platte River Valleys. Except for about 3,000 cranes that occupy a 7-square-mile site near Llewellyn, virtually all of the birds use staging areas 1-3. About 69 miles of channel are utilized as roosting habitat.
Approximately three-quarters of the crane population stages along segments of the 71-miles reach between Overton and Grand Island; the remainder occur west of North Platte. The span of channel that sand hill cranes now occupy is markedly reduced from former periods. The cranes have abandoned the 60.5-mile reach between the Tri-County Canal intake and its discharge site near Overton. Much of this reach was probably lost in the decade immediately following dewatering of much of the channel in 1941. However, several thousand cranes did remain as far west as Cozad in 1954. By 1979, the 23 miles of c h d between Cozad and the canal discharge site near Overton had also been lost. Between the Tri-County Canal discharge site and Kearney, a distance of 32 miles, an estimated 35,000 cranes still use the River. However, the advanced development of woody vegetation at many sites along this reach has resulted in a disjunct crane distribution. Eastward from Kearney , the channel remains relatively wide, averaging 200 yards and cranes roost throughout most of the reach to Grand Island. Recent surveys using aerial photographic techniques indicate that about 300,000 cranes use this area.
The midcontinent population of sand hill cranes during their annual stopover period in the Platte River Valley rely principally on three habitat types, a relatively broad channel for roosting, and cropland and meadows for feeding. The rapid rate of loss of riparian habitats used by cranes has promoted the need for development and implementation of a habitat preservation and management plan to stabilize conditions and thereby...
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