o 



CO I. Riverside Reservoir. Acreage: 3800. O 



Location: Weld County; Masters and Dearfield quadrangles; 30 miles E of -rj 



Greeley; reached via U.S. 34. > 



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Description: Riverside Reservoir is a large, man-made impoundment sur- ^ 



rounded largely by rolling, native grazing land. The reservoir and adjacent areas 

 provide habitat for a large variety of bird life. Breeding waterfowl include the 

 Mallard, Blue-winged Teal, Pintail, Gadwall, and probably other species. Several 

 thousand ducks of these species molted on the reservoir prior to about 1965. 

 Summer boating activities are thought to have contributed to the recent decline 

 in molting ducks here. Canada Geese have been introduced in the area and are 

 expected to nest in the next year or two. Waterfowl and shorebirds are espe- 

 cially numerous during fall and spring migration. Riverside Reservoir has a 

 unique population of White Pelicans nesting on the small islands associated with 

 this impoundment. At least five other species of birds nest on these same islands 

 (California Gull, Double-crested Cormorant, Snowy Egret, Forsters Tern, and 

 Red-winged Blackbird). 



References: Ryder, R. A., and J. R. Grieb. 1963. White pelicans breeding in 

 Colorado. Wilson Bull. 75(0:92; Hopper, R. M. 1968. Wetlands of Colorado; 

 Ryder, R. A. 1964. California gull nesting in Colorado. Condor 66(5):440-441 . 



Encroachments: Increased use of the reservoir by boating and water-skiing 

 enthusiasts in the future presents a threat to nesting and molting birds that now 

 utilize the area. Molting waterfowl have already been greatly reduced in 

 number, probably as a result of increased water sports activity. High water levels 

 inherent with irrigation reservoirs at certain times of the year sometimes cause 

 flooding of nests. 



Ownership: Riverside Reservoir and Land Co., 217 E. Kiowa Ave., Fort Mor- 

 gan, Colo. 80701. 



Data source: Richard M. Hopper, Game Research Center, P.O. Box 567, Fort 

 Collins, Colo. 80521. 



Other knowledgeable persons: Dr. Ronald A. Ryder, Department of Fishery and 

 Wildlife Biology, Colorado State University, Fort Collins, Colo. 80521; Dr. B. O. 

 Thomas, Department of Zoology, Colorado State College, Greeley, Colo. 



80631. 



