What are burrowing owls?

While they can dig their own burrows, they're often found in the burrows of ground squirrels, especially in California. While they'll still prep their own burrows to live in, they leave it up to the ground squirrels to clean them out after they move on.

To excavate burrows, owls face into the burrow and scratch backwards with their feet. Owls also walk through the burrow tunnel with out-stretched wings, dislodging dirt from the walls. In California and New Mexico, it's been reported that the owls will even use their bills to excavate.

After excavation, owls bring lining materials to their burrow's entrance. This material consists of dry horse, cow, and dog poop. 💩 Once an adequate pile of material is accumulated, the owls shred the material and carry it into the burrows. They line the nest chamber floor as well as the tunnel and entrance. The lining provides insulation and serves to camouflage the owls' scent, and its meal's, from predators. The poop can also serve to lure their prey, like beetles, into their burrow for a meal delivered.

Each pair uses multiple burrows, called their primary and satellite burrows.

When coupling up in the Spring, males will provide food for and perform a "bobbing" and "coo-cooing" to woo their mate. Females decide when their mate's wooing is adequate enough to copulate through "rasping."

Males tend to be slightly larger with lighter feathers, bleached by the sun, because, during the summer, it's his role to guard the burrow entrance while the female incubates their eggs inside.

However, once the demand for food from their chicks grows, both will hunt for food to bring home.

In the photo on the right, the male is on the left and female is on the right.

Burrowing owls spend most of their day hanging out by their burrow's entrance or on nearby short perches or mounds. The activities they can be found doing include:

• Sunbathing (top right photo)

• Stretching (bottom right photo)

• Eating

• Preening

• Preening each other

• Molting

• Roosting

• Dust-bathing

• Running

• Rousing

• Coo-cooing

• Feeding their chicks

• Teaching their chicks

• Wrestling

• Keeping watch for, hiding from, and defending against predators

• Bowling prairie dogs

• Domineering

• Hunting

• Visualizing

• Playing with toys

The video below covers what it's like for a brood of owls to grow up over the summer. 😍

#1 Threat: Urbanization of grasslands and agricultural lands

Urban sites are subject to disturbance, habitat loss, and poor habitat conditions. Less habitat means fewer places for the owls to live and less to eat where they can live.

Urbanization involves:

• • Development

  • Auto strikes

  • Exterminating rodents

  • Secondary poisoning

  • More mesopredators (badgers, foxes, skunks, etc.) & corvids (crows)

  • Weed abatement & Tall grass

  • Recreationists, Dogs & Cats

  • Surface and Soil disturbance

Relocation

Relocation has proved to have a very low success rate for the owls, so it should only be done when absolutely necessary. Multiple studies have been conducted by conservationists over the years, and all results aren't ideal. For more details of the success rate of their projects, see slide 83 of this deck.

Government Regulation

There are multiple federal and state rules such as the federal Migratory Bird Treaty Act and the state California Fish and Wildlife Code (Section 3503.5) that prohibit the taking, possession, or destruction of any burrowing owl, bird or body parts, young or adults, nests, eggs, or products. There are also state regulations requiring developers to survey land (see photo on right) for burrowing owls before development. For a full list of all the federal and state regulations that help protect and assist the burrowing owl, see slide 67 of this deck.

Habitat Enhancement

Conservationists can increase owl populations by enhancing the habitat of existing burrowing owl nesting sites or by attracting the owls to new ones. The owls can do well in developed, urban, and agricultural areas if nests are protected from disturbance and there is enough foraging habitat.

Principles for successful habitat enhancement:

1. Develop a long-term plan that sets aside adequate areas for burrowing owl protection and management; exclude disturbance activities.

2. Enhance sites for nesting with artificial burrows. (See photo on right)

3. Enhance the site for ground squirrels by bringing in mounds of dirt (don't use good soil!) and encourage healthy ground squirrel populations.

4. Keep grass short (<6 inches) around nesting burrows and remove trees.

5. Enhance foraging opportunities by creating a structurally heterogeneous prey habitat; no pesticides or poisons. This is what we're doing by planting California Native plants at Burrowing Owl Billows in Shoreline Park❗️

See slide 72 of this deck for more about habitat enhancement.