West Nile Virus Antibody Surveillance in Three Sierra Nevada Raptors of Conservation Concern

• Published in: The Condor
• Main Authors: Joshua M. Hull, John J. Keane, Lisa Tell, Holly B. Ernest
• Format: Text
• Language: English
• Published: American Ornithological Society 2010
• Subjects: Accipiter gentilis; Strix nebulosa
• Online Access: https://doi.org/10.1525/cond.2010.090110

West Nile virus (WNV) infection has caused high levels of mortality in North American hawks and owls. To investigate the extent of infection among raptors of conservation concern in the Sierra Nevada, we tested 62 Northern Goshawks (Accipiter gentilis), 209 Spotted Owls (Strix occidentalis), and 22 Great Gray Owls (Strix nebulosa) for WNV antibodies during the summers of 2004 to 2007 and compared our results with avian WNV mortalities detected by the California Department of Public Health. We detected no antibodies to WNV among the individuals tested. During the same period WNV RNA was detected in dead birds from 26 species in the Sierra Nevada region. These results suggest that the populations we studied were not exposed, that the level of WNV infection was so low as to be undetectable by our sampling scheme, or that the mortality rate from WNV was high enough to leave no surviving individuals; there is no independent evidence of the last alternative.