Cava et al. • DIET OF URBAN BREEDING COOPER'S HAWKS 
781 
prey for many nesting populations of urban 
Cooper's Hawks. House Sparrows and starlings 
are common prey of Cooper’s Hawks breeding in 
Milwaukee. Wisconsin (W. E. Stout and RNR. 
unpubl. data), and Grand Forks. North Dakota (T. 
G. Driscoll, unpubl. data). House Sparrows are 
also common prey of breeding Cooper's Hawks in 
Albuquerque. New Mexico (European Starlings 
are mostly absent from Albuquerque; B. A. 
Millsap and R. K. Murphy, unpubl. data). 
Apparent widespread use of House Sparrows 
and European Starlings in association with 
generally higher densities of birds in cities could 
in part be responsible for urban Cooper’s Hawks 
(including the Victoria Cooper’s Hawk popula¬ 
tion) attaining some of the highest nesting 
densities and reproductive success known for this 
raptor tRosenfield et al. 1996; Marzluff cl al. 
1998: Rosenfield et al. 2007a: ACS, unpubl. data). 
There is evidence that some cities serve as 
population sources for Cooper's Hawks and prey 
availability has been suggested as having a key 
role in this demographic progress (Mannan ct al. 
2008, Stout and Rosenfield 2010). 
ACKNOWLEDGMENTS 
We thank Phil Barker. Suzanne Benuchcsne. Eileen and 
Tesa Campbell. Jason Clark, Bryan Gates. David Gaunt. 
Laura Gret/.i tiger, Robert Hagel, David Hill. Neil Horne, 
Ignocz. Kadar, Manami Kaktl. Paul I.eBlanc. Brian Low, 
William Muekic, Lance Regan, Marie O'Sliadghnessy, 
Mari Smuby-Stone. Boh Chappell. Bret Ferguson. Darren 
and Gini MeKellar, Brad, Laura, and Irene Stewart. Audrey 
Wellburn. George Whitman, and others for project 
assistance. Michael MeNall provided access to the 
vertebrate reference collection at the Royal British 
Columbia Museum. Funding and logistical support was 
provided by the British Columbia Ministry of Environment. 
Habitat Conservation Trust Fund. Public Conservation 
Assistance Fund. Saanich Parks Department, British 
Columbia Hydro. James L. Baillie Memorial Fund. Shaw 
Cablesystcms, Pacific Forestry Centre, and Victoria Natural 
History Society. Financial support for RNR's participation 
came primarily from the Personnel Development Commit¬ 
tee. Letters and Science Foundation, and the Department ol 
Biology at the University of Wisconsin-Stcveas Point. 
Financial support for JAC came from the Honors Internship 
Program at the University of Wisconsin-Stevens Point We 
thank C. E. Braun. R. W. Mannan, and an anonymous 
reviewer for suggestions that improved this manuscript. 
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