Artificial burrows are used throughout the Burrowing Owl’s range — in British Columbia, Saskatchewan, Washington, Oregon, Idaho, Arizona, Colorado, California, Texas, Florida, Aruba, Brazil, and soon Venezuela. “The strategic use of artificial burrows is to try to mitigate for the loss of fossorial mammals, to ‘move’ owls away from unsafe development/construction areas, to support owls during reintroduction/translocation projects, and to strengthen owl numbers where very small populations are vulnerable to extirpation,” Johnson explains.
A recent paper in the Journal of Raptor Research reported that Burrowing Owls that used artificial burrows at study sites in northern California had “significantly higher” rates of nesting success than birds at natural burrows.
“At one site, nesting success at artificial burrows was 83% compared to 76% at natural burrows; at the other site, nesting success at artificial burrows was 96% compared to 75% at natural burrows,” reports author Sandra Menzel, a wildlife biologist for a California-based consulting company. To keep the burrows useful for the long-term, they need to be maintained regularly, including the tunnel and nest chamber, she found.
Menzel also notes that after owls are raised in artificial burrows, they tend to move around in subsequent years. “Of 120 Burrowing Owls raised in maintained artificial burrows and resighted during subsequent breeding seasons, 70% occupied artificial burrows and 30% natural burrows,” she writes. “Only 3% of these owls occupied their natal burrow during the first nesting season post-fledging. Of those owls that were resighted during two or more nesting seasons, almost half (48%) occupied different artificial burrows from one year to the next; therefore, the number of artificial burrows at a management site should be sufficient to provide opportunities for Burrowing Owls to move between nest burrows from year to year.”
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I can attest from personal experience that the burrows are no easy task to install. Johnson has installed hundreds. The burrows consist of a nesting chamber made from half of a 55-gallon plastic barrel, a 10-foot corrugated plastic pipe acting as the tunnel, and a set of pails that sit atop the nesting chamber. When the top pail is lifted, researchers can readily check on nests.
Great care was taken to make the entrances of the artificial burrows noticeable from the air, as a natural badger or tortoise burrow would be. To an owl flying above, it basically looks like welcome mats everywhere on the landscape. Through years of trial and error and by further understanding the bird’s preference and needs, Johnson has created a vast “city” of Burrowing Owls on the Depot.
Something to celebrate
It was the midafternoon when I set out with other volunteers on Johnson’s project to check on burrows and see how eggs and chicks were doing. We were looking to answer basic questions: Are they still there, are they still alive, are they banded, and are there signs that the parents have abandoned a nest? One of the first nests that we checked still had eggs. Based on the time of year, this was not a good sign, and sure enough the clutch was abandoned. With a cold egg in hand, I was able to appreciate its light white color. It was almost spherical in shape and tiny — just smaller than a ping-pong ball.
During my time at the site, I saw firsthand that Johnson and his crew’s efforts were working. Where there were once just a few birds, now there were many, and most of them were having offspring.
On one banding occasion, a 23-day-old chick lay belly up in the palm of my hand during its examination. With wings tucked, feet up, and a downy coat that felt like air itself, the little bird was something out of a bird bander’s dream. It was as calm as calm could be. Not only was I holding the oddest-looking stuffed animal I had ever seen, but it was also staring back at me with a similarly confused look.
The Burrowing Owl is an incredible subterranean bird, and fortunately, many people and organizations work to help the species. Witnessing this grumpy, fluffy sphere of a bird was a reward in and of itself, but watching its numbers increase in given areas is truly something to celebrate. As we finished banding for the day, I stood in the middle of a vast expanse of grass and sky in northern Oregon and was happy for the progress the birds have made at the Depot. The work that was put toward their survival and the fruit of that effort being made manifest defines the term fulfillment.
Working for owls
In addition to his work with Burrowing Owls in Oregon, David Johnson heads the Global Owl Project, an 18-year-old consortium of 450 researchers, managers, geneticists, museum curators, graduate students, and passionate volunteers in 65 countries who work on the science and conservation of owls. “We work on all living owls of the world, as well as all extinct and fossil owls,” he explains.
The project has seven main tasks: 1) survey and monitoring techniques for the owls of the world, 2) acquiring DNA samples, 3) getting high-quality recordings of owl vocalizations, 4) acquiring morphological descriptions and a research library of all scientific literature on owls, 5) developing refined distribution maps for conservation planning, 6) assessment of owls in myth and culture, and 7) dissemination of all project materials, reports, and publications.
Johnson became interested in owls when he was a boy camping in the woods in southern Minnesota in 1967 and an Eastern Screech-Owl perched on top of his tent. He was lying inside and could see the bird’s silhouette as it called out into the night for nearly 20 minutes. “I thought to myself, that little owl could have landed anywhere else, but it decided to land on my tent in the middle of that forest,” Johnson says. “Ever since then, I like to say that I didn’t chose to work with owls, but instead they chose me.”
How to help
Global Owl Project
Worldwide effort to advance foundational aspects of science and conservation for the world’s owls.
Burrowing Owl Preservation Society
Dedicated to helping owls through education, research, and protection and enhancement of grassland habitat.
Burrowing Owl Conservation Society of British Columbia
Working to restore Burrowing Owls to the grasslands of British Columbia.
Burrowing Owl Conservation Network
Advocates for the protection and restoration of the Western Burrowing Owl.
Cape Coral Friends of Wildlife
Citizens who want to help the area’s famous Burrowing Owls.
Audubon Society of the Western Everglades
Coordinates Owl Watch, a community science program monitoring Burrowing Owls on Marco Island, Florida.