Photos taken by Conservancy staff on Conservancy mitigation land, 2023.
The Burrowing owl (Athene cunicularia) is one of the HCPs’ “Covered Species.” And, we on the Conservancy staff freely admit, it’s a favorite. The reason is simple: these birds are so gregarious and fun to watch, they are irresistible.
Some 20 years or so ago, the Conservancy, working in cooperation with the Natomas Central Mutual Water Company and a rice farming tenant, constructed what we believed then to be ideal nesting areas for the owl. We were going on the best available information at the time, and guided by several experts, mostly a subject matter expert at the California Raptor Center, a UC Davis, School of Veterinary Medicine affiliate. (You can see that there was a lot of collaboration on this one!)
After construction, the embankment we constructed and added Burrowing owl features to was quickly occupied. After some years of occupancy, however, the nest sites were vacated. We assumed that the birds simply couldn’t find enough prey, given that the site we chose was surrounded by rice paddies. We believed there was abundant prey in rice fields, but, we assumed, since the fields were flooded for roughly four months each summer, foraging opportunities were far from localized, and the owls’ foraging range was made too great. So, they moved on, for reasons we could only guess. (When rice paddies are de-watered, we typically see populations of large insects and small rodents re-emerge in the fields and thus become available for the Burrowing owls.)
The rice field location for the Conservancy’s Burrowing owl nesting site experiment was chosen partly because of a series of bad outcomes on dry land and upland areas. We’d experienced coyote predation on the Burrowing owls in such locations, with plenty of evidence and documentation. (We also experienced predation from neighborhood dogs, which was astonishing to us.) Although coyotes do visit rice fields in the growing season, we don’t see them there very often. Maybe this is why the owls have come back: less threat by one of their biggest predators.
Happily, the Conservancy’s experiment has paid off, although some patience was in order. In these photos, you can see photo-documentation of one of our friends at the experiment site in the Conservancy’s Central Basin Reserve Area. We couldn’t be more thrilled to have one of the HCPs’ most interesting creatures back on Conservancy property and appearing as robust and healthy as ever.
