In addition to field surveillance and pathogen testing of mosquitoes, we participate in the California Department of Public Health’s (CDPH) West Nile virus dead bird program. Encephalitis viruses are maintained in wild birds since Culex mosquitoes are the primary vector of these pathogens and prefer to feed on birds. Therefore, any abnormal increases in the mortality of birds, such as crows, ravens, jays, sparrows, and finches, can be an indication of the prevalence of encephalitis viruses in the region. Reporting and testing dead birds is an important part of disease surveillance. 

Please report any dead bird(s) you encounter to the WNV Dead Bird hotline (877-968-2473). Based on your reports, the Department of Public Health may test the bird for the presence of viruses and notify us to increase our surveillance of mosquitoes for those viruses. Again, if you find a dead bird, please report it to the CDPH by calling (877-968-2473) or by reporting the location online at: www.westnile.ca.gov.