Landers: Turkeys can’t take full blame for grouse decline

Grouse hunters peg the blame on non-native wild turkeys.

While turkeys have boomed in recent decades, native forest grouse have declined. That’s proof enough for some hunters.

Casual observations offer some credibility to the indictment, but biologists tend to think it’s overblown and detracting attention from the larger problems.

The same discussion endures in eastern states, where wild turkey populations exploded over 30 years while a concurrent and equally spectacular decline occurred in ruffed grouse numbers.

A Spokane hunter recently queried The Ruffed Grouse Society about the turkey vs. grouse controversy.

Gary Zimmer, the society’s coordinating biologist, responded with thoughts backed by researchers’ articles. Among his key points:

• A species that’s expanding its range can hurt an established species, but this rarely happens with species, such as turkeys and grouse, which historically have coexisted.

• Research using radio telemetry or cameras documented that grouse nests suffer predation, but rarely if ever by turkeys. (However, a turkey was photographed picking up egg shells from an already predated quail nest. Calcium in egg shells is a nutritional attraction to a variety of wildlife species.)

Scientists in the eastern half of the U.S. conclude that turkeys and forest grouse have largely different habitat preferences and don’t compete for food or space.

“But this is a persistent topic of conversation among biologists as well as hunters,” said Mike Schroeder, Washington Fish and Wildlife Department wildlife biologist who specializes in grouse.

Schroeder generally agrees with the eastern research, although being a scientist, he wonders if it totally applies to the Northwest.

Unlike eastern states, Washington has seven grouse species:

• Sage and sharp-tailed grouse live in the shrub-steppe lands of north-central Washington.

• Ruffed grouse favor foothills creek bottoms that extend into deciduous and conifer forests.

• Spruce grouse, also known as Franklin’s grouse, are common in North Idaho forests, but confined mostly to the Okanogan region forests in Washington.

• Blue grouse prefer forests, where they migrate to high ridges in the fall. Blues are called “sooty grouse” on the Pacific side of the Cascades and “dusky” in the interior.

• White-tailed ptarmigan prefer the high rock and heather slopes of the North Cascades.

“We have booming turkey populations in areas with a wide variety of habitats affecting most of these species,” Schroeder said.

But he stops short of concluding that turkeys are crowding out grouse.

“Competition can be indirect,” he said. For example, turkeys could be luring more crows and ravens and other predators might influence the grouse population. 

Nonnative species might live with parasites fatal to other species.

Lacking funds for large-scale studies, there’s a lot Schroeder cannot conclude, but he’s confident in listing key pressures affecting Washington’s forest grouse:

  • Landscape level changes. For example, forest fires that exploded since the mid-’90s after decades of fire suppression.

• Development and rural homebuilding, especially on low-elevation breeding areas for dusky grouse.

• Changes in forests as logging is followed by reforestation and maturing stands.

• Pine beetle damage to forests in the Kettle Range and other areas.

• Impacts on aspen stands, which are important to ruffed grouse. These include fire – or lack of fire – as well as development and grazing – both by livestock and elk. (The impact elk had on aspen led to allowing big-game hunting in Turnbull National Wildlife Refuge.)

“The bottom line is that we know some, but we don’t know for sure about the competition between turkeys and grouse,” Schroeder said.

That’s not likely to change as long as sportsmen care more about turkeys, pheasants and other species than they do about grouse.

“I wish I could do something to increase the positive profile of grouse,” he said, noting that even within his agency there’s little incentive to pay more attention to native forest grouse.

“The grouse in this region are a world-class resource,” Shroeder said.

Indeed, people spend thousands of dollars traveling to Scotland to bask in the traditions of hunting grouse.

Here, most grouse are harvested by road hunters.

“The danger is that we just go along not knowing much about the grouse species,” Schroeder said.

“If it’s true the species are headed toward trouble, by the time we figure that out, the only affordable option is to just close down the hunting season.”

Contact Rich Landers at (509) 459-5508 or richl@spokesman.com.