Federal officials are planning to hire hunters with shotguns to exterminate tens of thousands of cat-sized barred owls in California and the Pacific Northwest as the birds "invade" from the east.

The U.S. Fish and Wildlife Service says barred owls represent an invasive threat to their cousins, Northern spotted owls, which are protected by the Endangered Species Act. Without action, officials said, the approximately 7,000 spotted owls left could become essentially extinct in the near future.

"We have been asked whether it is ethical to kill one species for the benefit of another," officials said in announcing their plan. "While we understand the concerns, the service has an obligation under ESA to recover listed species by addressing the threats to that species."

Why are officials planning to kill barred owls?

Federal wildlife officials say the barred owls, which are bigger, hungrier and better breeders, are moving into new territory and out-competing spotted owls.

The barred owls never used to live in the Pacific Northwest and California, but have moved west as European settlers cut down forests and disturbed East Coast ecosystems, officials said.

While barred owls can live in most places, spotted owls prefer old-growth and mature forests, which are also prized by loggers. Barred owls started being seen in the Pacific Northwest in the 1970s, federal officials said.

Officials said northern spotted owl populations in the northern half of the species’ range ‒ where barred owls have moved in most aggressively ‒ have dropped by more than 75% in 20 years.

Officials didn't put a price tag on their effort but said killing the estimated 60,000-100,000 barred owls across a portion of the West twice the size of Vermont would permit the spotted owl population to rise to about 8,400. Officials said their plans wouldn't threaten barred owls' overall existence because they are so widely distributed nationally.

What does the plan call for?

To create space for spotted owls to continue breeding, authorities would aim to kill about 20,000 barred owls in the first year, and then continue killing them for the next 30 years. Extermination would take place on federal and tribal lands, and private land with owners' permission.

Officials examined multiple alternatives, from relocating the barred owls to housing them in zoos or even dosing them with birth control. They also considered whether it would be better to trap and then euthanize the owls, but decided that hiring hunters was the most humane solution.

This isn't the first time officials have targeted the barred owls: starting in 2013, authorities killed them off in small test areas and found the spotted owl population of those areas stopped shrinking as a result.

How would it work?

Hunters armed with shotguns would deploy into the areas and play barred owl sounds. Because barred owls are territorial, they would investigate and be shot at close range. Officials said they would take precautions to avoid killing any spotted owls, but would also try to kill hybrid barred-spotted owls, which are just as aggressive as pure barred owls.

In more populated areas, officials might try to trap or net the owls instead.

Does anyone oppose this plan?

The environmental group Friends of Animals has been trying to block barred owl exterminations for years, arguing that while humans might have caused the conflict in the first place, it's not our role to fix it.

"While human-induced changes in animals habitats is certainly a bad thing, once they happen animals need to be able to sort it out—even if that means some species become threatened or endangered—without human interference," Michael Harris, the director of Friends of Animals’ Wildlife Law Program, said in a September statement. "We may have wrongly set the situation in motion, but we are only interfering further by trying to make it better for our 'preferred' species."

Haven't I heard of spotted owls before?

Spotted owls have long been part of an ongoing fight between Republicans and Democrats over the appropriate role of government, the Endangered Species Act and the economic consequences of protecting wildlife.

First protected by the ESA in 1990, the owls were then used in a series of lawsuits by environmental groups to shut down logging across large portions of the Pacific Northwest. Those logging battles continue to this day, with Republican presidents typically trying to expand logging at the expense of the owls, and Democrats trying to protect the owls, causing widespread economic harm to logging communities.

There's even a reference to them in the 2013 Leonardo DiCaprio movie "Wolf of Wall Street."

Environmental groups have accused logging companies of trying to protect barred owls because their presence keeps out spotted owls, allowing logging in areas that might otherwise be off-limits. Fish and Wildlife officials said they didn't expect the plan to kill barred owls to significantly change the amount of forest open for logging.

President Joe Biden recently unveiled a plan to protect large portions of forests favored by spotted owls.