Scientists and wildlife preservationists have spent the past five years attempting to save the northern spotted owl in the US, no matter the cost – which has so far included killing thousands of other birds, according to an article published in Science.
The spotted owl’s population has been declining due to the arrival of barred owls in the western US, which has pushed them out of their habitats and further towards extinction.
The barred owl and the spotted owl share many similarities and are closely enough related to mate and produce fertile offspring. But when barred owls arrive in spotted owls’ territory, the result is not always a union.
Barred owls have an aggressive streak not present in the spotted owl, and will drive spotted owls away from their nesting sites, according to Eric Forsman, a US Forest Service wildlife biologist.
“You get this population of old birds with no young coming on,” he said.
Killing barred owls may be only option
While killing so many birds feels antithetical to many of these conservationists’ ideals, shooting the barred owls appears to be the only option to save the spotted owls, according to Science.
It is also one that’s working.
In 2009, wildlife biologist Lowell Diller and the timber company Green Diamond Resource began a five-year experiment shooting barred owls on land in Northern California. At the conclusion, Diller found that spotted owl numbers stabilized in areas where the barred owls had been killed.
Larger experiments have since mirrored the results.
Across Washington, Oregon, and California, 2,485 barred owls were killed in tests ending in 2019. Again, spotted owl numbers stabilized in areas where barred owls were shot, but dropped by 12% per year in untouched areas, according to Science.
The study was enough to convince the US Fish and Wildlife Service (FWS) to take a more drastic step, releasing a plan to use specially trained teams of owl shooters to create spotted owl refuges across the three states in 2024.
While the plan is voluntary for landowners and public land managers and the shooting has been limited, at maximum scale, the plan would cover over 50,000 square miles and kill 450,000 owls over 30 years, Science wrote, continuing indefinitely.
Owl saved from extinction before
This is not the first time federal action has been taken to save the spotted owl. In past decades, widespread logging was pushing the species towards extinction, Science wrote.
However, in 1990 it was listed as threatened under the US Endangered Species Act, and courts halted most logging in the old forests that form the owl’s habitat on federal land.
In 1994, the Northwest Forest Plan put large areas of the owl’s habitat off-limits to logging.
The threat then shifted to the influx of barred owls.
While it is unclear exactly what led to their expansion across the US, the FWS stated that it is believed to have begun around the turn of the 20th century.
One leading theory is that as European settlers planted trees on farms and suppressed Indigenous fire-setting practices and traditions, a bridge of trees was created across the prairie.
Others believe that global warming made forests in new areas more hospitable to the owls.
Source:
www.jpost.com
