Protecting the Western Burrowing Owl in California

The charismatic, tiny burrowing owl was once found in nearly every arid open landscape throughout South America to the United States-Canadian border. They are named for their unusual nesting habits in underground burrows rather than up in trees.  

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Richard Reading

Populations of these diminutive raptors, however, are under increasing pressure from habitat destruction and land use change with no legal framework to meaningfully protect them. Because of the significant declines of burrowing owls in California, Defenders of Wildlife and other conservation groups have twice petitioned to protect western burrowing owls under the California Endangered Species Act.  

The first attempt in 2003 was unsuccessful largely based on the assumption that individuals from stable populations could augment declining populations elsewhere in the state, which has unfortunately not been the case. In March 2024, Defenders and our partners submitted an updated petition focused on protecting five of the most imperiled populations of the owl in the Golden State.  

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Dan Fillipi

The western burrowing owl plays a valuable role in both urban and wild environments by reducing the spread of disease in cities and agriculture fields.  

Cutest Cave Dwellers  

The burrowing owl is one of the smallest owl species. Adults are about 7 to 10 inches tall, standing on bare, stilt-like legs. They have bright yellow eyes, a distinctive facial ruff and coloring that helps them blend into the fields in which they live.  

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Randy Traynor

Burrowing owls usually take over the burrows excavated by badgers or other burrowing animals. Some, like populations in Florida, may dig their own owl home as the soil is soft enough. In California, though, the western burrowing owl usually lives in former ground squirrel nests.  

These owls typically live in colonies, which may be due to availability of burrows and food, or an adaptation to mutual defense. During nesting season, adult males will find burrows near the mother birds, creating a border to defend against predators or other burrowing owls.     

Loss of open space in California due to urban expansion as well as conversion of grasslands to agricultural lands has led to significant habitat loss for the western burrowing owl, forcing them to try to make homes in pipes, culverts and ditches.  

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Pixabay

Competitive Habitat in California  

There is suitable habitat for these owls – i.e. flat, treeless areas – throughout much of California. Sadly, however, a very small percentage of the state’s original prairielands remain.  

The highest population abundances of these owls in California occur in wide, interior valley bottoms and flat coastal lowlands, much of the same areas under the most severe pressure from urban development.  

Because no federal or state law currently requires land developers to protect western burrowing owl habitat, this vulnerable species continues to decline. This is why Defenders is fighting for the state to list the western burrowing owl under California’s ESA and will continue to advocate for protections for this species throughout its range.