Across the vast open lands of the western United States, miners often use uncapped plastic pipes to designate the locations and boundaries of their mining claims. But these millions of open polyvinyl chloride pipes are deadly for small birds: Attracted to the openings as potential nesting cavities, the birds get stuck within the pipes' smooth, narrow walls.

Now, American Bird Conservancy and more than 100 organizations — including the Cornell Lab of Ornithology, Earthworks, and Tucson Audubon Society — are urging two federal agencies to accelerate their efforts to address this longstanding threat to birds.

In a joint letter last month to the Department of the Interior's Bureau of Land Management and the Department of Agriculture's Forest Service, the groups pressed the agencies to meet their responsibilities under the Endangered Species Act and the Migratory Bird Treaty Act.

Mountain Bluebirds are among many species that become trapped inside uncapped pipes used to mark mining claims. Photo: Mountain Bluebird, Tome Reichner/Shutterstock.

Among the groups' recommendations are the development of national policies to remove or modify existing pipes, and federal regulations that would require non-hazardous markers on all future mining claims. The groups also urge the two agencies to stop the use of open pipes for fence posts, gates, and outhouses.

Cavity Nesters Are Frequent Victims

Mine claim markers threaten birds across a huge swath of public lands from Oregon to New Mexico. According to BLM estimates, in 2014 there were 3.5 million mining claims on lands the agency manages in 11 contiguous western states and Alaska. Nevada had the most (1.1 million claims), followed by Utah (412,000); Wyoming (314,000, including small numbers from Nebraska); California, (311,000); and Colorado (285,000).

One examination of 854 pipes in Nevada revealed 879 dead birds, along with 113 reptiles and 20 mammals. The Nevada Department of Wildlife has recovered 43 species of birds from the markers. Some pipe-pulling efforts have revealed as many as 30 dead birds in a single pipe.

Most of the trapped birds are cavity nesters: The Ash-throated Flycatcher and the Mountain Bluebird are the most frequent victims, but also at risk are woodpeckers, sparrows, shrikes, kestrels, and owls.

Ash-throated Flycatchers are another species at risk of becoming trapped in the pipes. Photo: Greg Homel

A single pipe can be disastrous. In 2011, BLM specialists in Oregon documented alarming rates of bird fatalities at claims in the eastern part of the state, near Burns. In a written report, one specialist stated that the toll to birds “could be enormous…a single uncapped, vertical PVC cylinder can potentially entrap and kill dozens of native birds from multiple species.”

Reducing Threats from Pipes

Federal agencies have already taken some steps to mitigate the threat. BLM created a flyer — endorsed by American Bird Conservancy and the National Mining Association — that will be mailed to mine claim holders, alerting them to the problem and urging them to replace or remediate hazardous markers. Meanwhile, Forest Service staff are covering open vent pipes on outhouses that were trapping birds.

You can take action and encourage federal officials to implement additional protections for birds by contacting the Bureau of Land Management and the Forest Service.