Studies Indicate Ravens Preying on Endangered Sage Grouse Eggs

When you think of a raven, you might think of Edgar Allen Poe’s famous poem.

"The Raven" depicts a mysterious raven's midnight visit to a mourning narrator. (1858).

John Tenniel / via Wikimedia

\”The Raven\” depicts a mysterious raven\’s midnight visit to a mourning narrator. (1858).

But those “ominous birds of yore” are following energy development around the West, and several new studies show ravens are feasting on the eggs of another iconic bird –  the sage grouse – further threatening a species on the brink of extinction.

Now, the U.S. Fish and Wildlife Service wants to control the ravens – lethally.

One of the best places to go raven watching is, strangely enough, a  landfill, explained wildlife ecologist Dr. Charles Preston. Why? Scientists call it a disturbed landscape, a dump in the middle of wild sagebrush habitat.

“Ravens are one of the few species that we know will communicate with one another about a distant activity,” Preston said.

That kind of communication is called displacement. Ravens can gather and pass  information, then the following day they show up by the dozens at a fresh roadkill carcass. He says it is this intelligence that makes ravens formidable predators to sage grouse.

“It’s a challenge because they are so smart,” Preston said.

Jonathan Dinkins, a University of Wyoming researcher, is working on a  four-year study of ravens and their effects on sage grouse nests.  “There are raven hot spots,” he said.

Other studies in Nevada and Idaho agree: Raven populations aren’t out of control everywhere, just in areas where humans have disturbed sagebrush habitat. In other words, ravens and oilfields often are a one-two punch for sage grouse. Dinkins’ study and others all seem to show that more ravens mean fewer sage grouse are hatching.

Western sage grouse

Western Governors' Association.

Western sage grouse

Dinkins said you can’t necessarily assume raven hot spots are just around energy sites. But the kind of sprawl and traffic and roadkill that come as part of  oilfield development does mean more ravens.

In the past, because ravens are protected as migratory birds, they could only be killed to protect livestock or human health. But in coming months, U.S. Fish and Wildlife will be able to use poison control on ravens to benefit  sage grouse.

Ideally, that will only happen in those areas where raven hot spots overlap with the best sage grouse habitat, Dinkins said.

Tom Christiansen, Wyoming’s  sage grouse coordinator, said sage grouse nests are more successful where ravens have already been killed.

But, he said, killing ravens would only be a temporary fix because ravens are territorial. An empty roost is like an empty hotel room at Cheyenne Frontier Days – it fills up instantly.

And that’s why ecologist Charles Preston says a campaign to kill ravens could be an uphill battle. The best way to control ravens, he said, is to bring sagebrush country back into balance: Cluster energy structures in limited areas, close down dumps in sage grouse habitat, and help raven predators thrive.

Natural raven predators include golden eagles, weasels, coyotes and owls.

“That’s the natural biological control,” said Preston.

He said ravens aren’t Poe’s evil bird – they’re just opportunists. To control them, he says we need healthier sage lands. Otherwise, the greater sage grouse could be … nevermore.

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