Innovative screens help save tiny western owls

Northern Saw-whet Owl at Bartel Grasslands, Cook County, Illinois, by mike.

Northern Saw-whet Owls and Western Screech-Owls are tiny birds. Each weighs between three and seven ounces, or about the same as a small cell phone or a deck of cards.

See photos of Northern Saw-whet Owl.

See photos of Eastern and Western Screech-Owls.

They prefer to nest and roost in dark, narrow spaces, including man-made cavities. On some public lands, the habitat preference has caused the owls to become trapped in ventilation pipes on vault toilets. Many have died.

Public agencies use vault toilets to manage sanitary waste on their lands. The structures rely on the sun to heat the vent stack on the roof. The warmth causes air in the pipe to rise, pulling unpleasant-smelling air out of the building. The owls enter at the top of the vent, fall down the pipe, and land in the waste-holding reservoir. Because the pipe is vertical and narrow, and made of plastic or metal, the birds are unable even to climb out.

The Caribou-Targhee National Forest occupies about three million acres in Idaho and Wyoming and a bit of Utah. Engineers there designed a screen that would prevent birds from entering but would not affect the functioning of the vent stack. Thanks to Teton Raptor Center staff, community organizations, and participating land agencies within the Greater Yellowstone Ecosystem, more than 500 screens will have been put in place by the end of 2014. Grants funded the purchase of the screens.

Because the program could save thousands of birds, it was recently recognized with an award from Wings Across the Americas, a U.S. Forest Service program aimed at conserving populations and habitats of birds, bats, butterflies, and dragonflies. The screen project received the Habitat Management and Partnership Award.

PVC pipes used in Nevada and other western states to mark millions of mining claims managed by the Bureau of Land Management pose a similar threat to birds. To help reduce it, ABC has pulled and discarded thousands of markers, developed outreach materials to educate mining claimants, and taken other steps. See “Eye on Conservation” in our June 2012 issue.

A version of this article appeared in the August 2014 issue of BirdWatching magazine. Subscribe.

Read an article by Julie Craves about Northern Saw-whet Owl.

This story was provided by American Bird Conservancy, a 501(c)(3), not-for-profit organization whose mission is to conserve native birds and their habitats throughout the Americas.