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Full-Text Articles in Population Biology
Spring Population Estimates Of Rocky Mountain Greater Sandhill Cranes In Colorado, Douglas S. Benning, Roderick C. Drewien, Douglas H. Johnson, Wendy M. Brown, Erwin L. Boeker
Spring Population Estimates Of Rocky Mountain Greater Sandhill Cranes In Colorado, Douglas S. Benning, Roderick C. Drewien, Douglas H. Johnson, Wendy M. Brown, Erwin L. Boeker
Proceedings of the North American Crane Workshop
We developed an aerial survey to estimate the Rocky Mountain Population (RMP) of greater sandhill cranes (Grus canadensis tabidn) (greaters) annually during March 1984-95 in the San Luis Valley, Colorado (SLV). We flew aerial transects covering a 21,220-ha contiguous area. Aerial photographs of crane flocks were taken to correct for estimation errors. We employed ground surveys to correct for presence of lesser sandhill cranes (G. c. canadensis) (lessers), which mixed with RMP cranes. To adjust for RMP cranes not in the survey area, we made ground counts in traditional use areas outside the SLY. During 1984-95, 5 …
Harts Basin, Colorado: A Spring Migration Stopover Area For Rocky Mountain Sandhill Cranes And Whooping Cranes, Melvin K. Peterson, Roderick C. Drewien
Harts Basin, Colorado: A Spring Migration Stopover Area For Rocky Mountain Sandhill Cranes And Whooping Cranes, Melvin K. Peterson, Roderick C. Drewien
Proceedings of the North American Crane Workshop
Greater sandhill cranes (Grus canadensis tabida) from the Rocky Mountain Population (RMP) and whooping cranes (G. americana) reared by RMP foster parents were monitored during 1980-95 at a traditional spring migration stopover at Harts Basin in western Colorado. Counts during March and April 1986-93 showed that a mean of 10,656 RMP sandhill cranes stopped annually for 1 or more nights en route from their spring staging area in the San Luis Valley, Colorado, to summer grounds. More than 96% stopped between 11 March and 10 April. Count data indicated that > 50 % of the RMP stopped …