- Sage Grouse Initiative (SGI) Program
- Hen Nesting Can Recur
- Telemetry Device is Harmless to Chicks
- Time of Day is Critical for Tagging Success
By Brianna Randall, Sage Grouse Initiative
Saving sage grouse saves more than 350 other species, including plants, insects and a host of wildlife. The Sage Grouse Initiative (SGI) is a partnership of ranchers, agencies, universities, non-profit groups, and businesses that embrace a common vision: wildlife conservation through sustainable ranching. One key in the success of the program starts with successful chicks and understanding where they are and how they are doing.
So how do you know when a hen has hatched her brood?
We go out on the ground every other day during the April-May-June nesting season using handheld three-element Yagi antennas to listen for each hen’s VHF radio transmitter in order to get a her location — a process called telemetry. Once a hen’s location doesn’t change for two consecutive checks, we go in to confirm whether or not she is actually on a nest. If she is on a nest, we mark a point at least 100m away, which becomes the remote monitoring site for that nest.
Each nest is assigned an estimated hatch date which is 27 days from the first day we found the nest. Every two days after that first marking, we check to see if the hen is still on the nest by listening with telemetry equipment and evaluating if the compass bearing of the hen from the monitoring point has changed. This bearing won’t change more than a few degrees if the hen stays on the nest.
If the hen is absent from the nest around the estimated hatch date, we go in to see if one or more eggs hatched successfully. Hatched eggs will have an even break around the middle with a detached membrane inside and are usually still in the nest bowl. Often, one end of the shell will end up stacked inside the other end.
What if a nest fails?
Nest predation is common, especially since sage grouse are ground nesters. The nest bowl is simply a shallow depression usually underneath a sage bush — easy access for hungry foxes, coyotes, snakes or ravens. If a hen is not on her nest, we go in to determine why she isn’t there. If the nest was found by a predator we often find evidence of predation: eggshells strewn about or eggs with holes in them.
If a nest fails, that hen goes back into our “tracking and monitoring” phase. It’s common for hens to make a second nest if her first nest fails, and occasionally even a third nest if the first two nests fail. We also continue to track the barren hens throughout the season to monitor their use of the surrounding sagebrush in relation to the different grazing treatments being used.
When do you tag the new chicks?
We try to tag chicks two days after they hatch. But it always depends on the weather. Chicks can’t thermos-regulate for the first 7-10 days of their life, which is why they often roost under their mom, particularly at night. We do everything possible to keep the chicks plenty warm during the capture process. Though it’s usually late May or June when they hatch, it can still get cold here in Montana, especially since we do the tagging at night. We always tag as close to sunset as possible, and only if it’s over 50 degrees F and there’s no rain, wet soil, or wind. Sometimes, that means we don’t get to tag the chicks until they’re close to a week old.
The Sage Grouse Initiative (SGI) is a partnership of ranchers, agencies, universities, non-profit groups, and businesses that embrace a common vision: wildlife conservation through sustainable ranching.
Launched by the USDA Natural Resources Conservation Service (NRCS) in 2010, SGI applies the power of the Farm Bill to fund and certify voluntary conservation projects in sage grouse strongholds across 11 western states. To date, the 1,129 ranches enrolled have conserved 4.4 million acres.
Next week, Part 3 of the series.
For more information on the Sage Grouse Initiative program or to become involved directly with the SGI program, visit: http://www.sagegrouseinitiative.com.