Burrowing Owl Protection
Burrowing Owl populations have drastically declined in many parts of their North American range over the last 30 years. Once common in grasslands, this species is listed as federally endangered in Canada since 1995, threatened in Mexico since 1994, and has special status as endangered, threatened, or a species of special concern in 11 states in the United States. In California, the Burrowing Owl was listed as a Species of Special Concern in 1978.
The conversion of grasslands to urban areas or agriculture, associated ground-disturbing activities (e. g., disking, trenching, and bulldozing), and the eradication of burrowing mammals are among the factors contributing to the population decline. Habitat conversion reduces natural burrow availability, foraging area, and prey abundance. As a consequence, owls are displaced from previously occupied areas, and their breeding opportunities may be reduced.
The San Francisco Bay Area, historically one of four primary Burrowing Owl nesting areas in California, has suffered steep population declines during the last 30 years. For many years, our Environmental Advocate (Shani Kleinhaus), Burrowing Owl Project Managers and Lead Biologists (Phil Higgins and Sandra Menzel), along with many volunteers and supporters, have been diligently advocating for the preservation, restoration, and enhancement of the Burrowing Owl and its habitat in the Santa Clara Valley and beyond.
© Tom Grey
2018 Burrowing Owl Update
In 2016, SCVAS in partnership with San Francisco Bay Bird Observatory (SFBBO) were awarded a 5-year contract with the Santa Clara Valley Habitat Agency (SCVHA) to manage the bufferlands of the Santa Clara/San Jose Wastewater Facility in Alviso. The work includes maintaining and enhancing the habitat for Burrowing Owls, and conducting monthly surveys to monitor the population. Each breeding season, our biologists count the number of breeding pairs and each pair’s offspring.
SCVAS staff and volunteers have managed this land for the City of San Jose for the last 6 years and we look forward to continuing our work. We enjoy the collaboration with and support of our dedicated SCVAS members, volunteers, and the team at SFBBO. The nesting Burrowing Owl population at this 200-acre site is now the largest sub-population in Santa Clara County.
In 2017, our Burrowing Owl biologists counted 17 pairs with a minimum of 29 young. Although reproductive success was lower compared to past years (this may be a result of extensive flooding on site for 5 months during the start of the breeding season), the overall breeding success at this site is encouraging compared to other locations in the region.
Although this is wonderful news, we have to continue our conservation efforts throughout the Santa Clara Valley as development pressures and habitat loss continue to increase, and the Burrowing Owl population decreases throughout its range.