Western Burrowing Owl Research
The Western Burrowing Owl used to be found living and nesting at many locations throughout the Bay Area. The charismatic bird is the only owl species that is active during the day and has always been a favorite among birders. Unfortunately, in recent years the species has been listed by the State of California as a Species of Special Concern. In California these owls are primarily threatened by habitat loss due to urban development, eradication of ground squirrels (which provide the burrows the owls use to nest), and intensive agricultural practices.
In 2015, we started partnering with others to monitor two of the last Burrowing Owl populations in the Bay Area. One project is at the Warm Springs Unit of the Don Edwards San Francisco Bay National Wildlife Refuge in Fremont. The other is at the San Jose-Santa Clara Regional Wastewater Facility near Alviso. Our biologists, partners, and citizen scientists conduct breeding and winter surveys to estimate population size and assess nest success; use nest cameras to capture predator behavior; and revitalize owl and prey habitat.