New research shows that a few individual greater sage-grouse travel more widely travel than anyone suspected, which makes the overall population stronger.
Photo by John Carlson – Over 7,000 sage grouse feathers were collected to study how sage grouse disperse across the landscape.
Greater sage-grouse are thought to return to the same breeding ground, or “lek,” every spring. But some scientists wondered how populations avoid becoming isolated and inbred.
A new study from The Condor: Ornithological Applications used thousands of DNA samples collected at leks across four states to reveal that some sage grouse travel more widely than anyone suspected.
By dispersing across larger distances, a few individual sage grouse make the overall population stronger by tempering inbreeding and isolation. This genetics study opens an exciting new door into understanding the landscape dynamics of this bird.
Using genetic markers in DNA extracted from 7,629 feather and blood samples, Todd Cross, a Sage Grouse Initiative scientist in partnership with the U.S. Forest Service Rocky Mountain Research Station, worked with colleagues to identify more than 3,000 individual sage grouse that visited leks across the northeastern portion of the birds’ range over seven years.
The study used samples collected from 835 leks in Idaho, Montana, and North and South Dakota between 2007 and 2013. Seven birds made movements of over 30 miles, six of which occurred within a single breeding season.
“Our research demonstrates that greater sage-grouse are an even more mobile species than we had realized before, moving large distances of up to 120 miles in a single breeding season,” says Cross. “These findings highlight the importance of landscape-scale efforts that conserve movement corridors.”
While the results support the idea that most grouse are faithful to their chosen lek sites, some individuals clearly make long-distance movements, which could help prevent inbreeding within leks and expand the size of the genetic neighborhood.
“Even contemporary telemetry techniques woefully underestimate animal dispersal,” says Sage Grouse Initiative coordinator Thad Heater. “New molecular techniques employed here for the first time enable us to quantify the appropriately large scales at which to deliver conservation strategies.”
Stay tuned this spring for the Sage Grouse Initiative’s upcoming Science to Solutions article, which will feature: 1) a summary of Todd Cross’ long-term sage grouse genetics research, 2) what it tells us about the health of the species as a whole, and 3) how proactive, voluntary conservation on private land is making a difference to conserve the large landscapes these birds need to thrive.