Entry 4 for today (if you're counting).

Regarding today's activities. We checked five strutting grounds this morning. Two west of the Continental Divide, two to the east, and one right smack dab on the Divide. Bird numbers on the leks on the west side were down a little, I think. This country had a really tough winter, and it may have affected grouse survival.

Know it was rough on the antelope. Found the carcass of a buck near the first lek. Actually it was just the skull, spine and hide. Everything else has been recycled. He was mature, at least four years old. His stage of horn growth suggests he died in February, maybe early March (the prong hadn't started growing yet). Found part of another winter kill along the road in. Couldn't identify sex, but the sealed epiphysis told me it was an adult. Broke one leg bone open. Marrow had dried up, but you could tell it had been red with little fat content left. Starvation.

Normally sage grouse don't have problems with winter. It's their fat season, when all they do is hunker down next to a clump of sagebrush and eat it all day long. Or all week long. In the spring you can tell which plants they favored by the little piles of curled grouse turds around the best plants. Appears as though they may not move for days at a time, or else they always come back to the same side of the same bush to roost. But little kills sage grouse during the winter except the occassionally lucky eagle.

A well-renowned sage grouse researcher has stated that "a sage grouse doesn't die until something comes along to kill it and eat it". An over-simplification, but basically the adults never have to worry about cold or food, as long as we keep sagebrush around for them to eat and hide in.

But bird numbers are down just west of the Divide here, and I wonder if the long period of deep snow cover may have made them easier for the eagles to find.

Here the west side of the Divide itself is a steep slope with large rock outcrops and terribly soft, erosive soil. The road has washed out lots of times, and there are several places you have to go cross country in brush higher than the hood of the truck to get up. And this time of the year the rising sun is directly in front of you. Had to get out and look once because I couldn't see and I thought the road was gone. It was.

Should have looked at least one other time. Got up OK, but on the way back down I couldn't believe the ditch I had straddled without knowing it.

Both leks east of the Divide were empty. One has been empty for years, and use on the other site has been tapering down (that's an inside joke... name of the lek is Taper lek). Found the feather remains of a predated male grouse on the lek, from early in the strutting season. Droppings also suggest birds were there early in the season, but then gave it up.

I think the reason they left that lek is the strutting ground that straddles the Continental Divide just over a mile away. It's a relatively new lek, and its numbers have been increasing. It's my suspicion that birds are shifting away from the eastern sites to use this one. Don't know why. Better acoustics and exposure? (That matters... can't attract hens if they can't hear or see you.) Perhaps it is harder for eagles to sneak up on. Either way, it is the new, hot singles place for grouse to court.

Had a bunch of sage thrashers singing this morning, first ones this spring. One of the best ways to locate a strutting ground is to just listen for the birds strutting (heard one lek from 4 miles off), but once the thrashers start singing, you can just about forget it. Melodious little suckers, but loud. And they seem never to shut up.

Corky's white truck looks real pretty against the green hills.