Birds at the Rawhide Energy Station - The 2006 Ryder Report

Since 1986 (21 years) Dr. Ronald A. Ryder, Professor Emeritus of Wildlife Biology, Colorado State University, has conducted an ongoing study of bird populations, mainly on Hamilton Reservoir. He has been documenting, by species and population numbers, birds using the Energy Station property, attempting to ascertain migration peaks, routes to places of breeding and wintering for the more abundant species (mainly waterbirds).

From 1986 to 2003 birds were captured and banded. Recoveries are still being reported for ducks and geese. Winter counts, especially in December, regularly were highest for individual birds, but fall and spring counts were noted for the greatest number of species. Midsummer was lowest for both species and individuals. Again Canada Geese and Mallard were the most abundant in late December on the annual Christmas Bird Count. Two “new” species were noted: the Eurasian Collared Dove (since 2002) and the Cackling Goose (see annual summary tables). The Collared Dove is a recent invader from the eastern states, an escapee from the Bahamas. The Cackling Goose was formerly considered a subspecies of the Canada Goose, but since 2004 has been recognized by the American Ornithologists’ Union as a full species.

Main “summer birds were again American White Pelican (157 on 22 June) and Double-crested Cormorant (88 on 18 August). Both are fish-eaters and probably from nesting colonies in eastern Colorado and southeastern Wyoming.

2000 Ryder Report
2001 Ryder Report
2002 Ryder Report
2003 Ryder Report
2004 Ryder Report
2005 Ryder Report
2007 Ryder Report

Statistics HTML pages:

Birds 1986-2011 (pdf) 8.5X14 (legal-sized)