USGS Report Finds Steep Sage-Grouse Declines, Despite Small Increase in Wyoming

From the Summer 2021 issue of Living Bird magazine. Subscribe now.

A grim federal report estimates an 81% decline in the Greater Sage-Grouse population over the last 53 years. The 260-page U.S. Geological Survey report published in March estimates a 3% annual decline over the past half-century.

“At 3% per year it takes 33 years to knock them out,” said Brian Rutledge, director of the National Audubon Society’s Sagebrush Ecosystem Initiative. [Note: this estimate is a slight overstatement. Because of the nature of exponential declines, the cumulative decline after 33 years, at 3% per year, would be about 63%.]

The analysis painted a bleak scenario for sage-grouse across 11 western states, but it found a bright spot in western Wyoming, where the report’s 11 authors found “slight growth” dating back to 1996.

Western Wyoming holds “the most contiguous habitat available range-wide,” said Peter Coates, the report’s lead author and a research wildlife biologist at the Western Ecological Research Center in Dixon, California.

The report, an amalgamation of data processed through scientific statistical models, proposes a standard method for counting and estimating sage-grouse population trends across the West. It also proposes an early warning system for areas where birds are in trouble.

The framework should help scientists determine what’s driving population declines, and what efforts might be working to stem a tide of losses.

The goal is to help “reverse these long-term declines these models have brought out,” Coates said.

This story was adapted from a longer version published April 8, 2021, by WyoFile, an independent nonprofit news organization focused on Wyoming people, places, and policy. Read the full story.