Yesterday we closed the book on 2011 behavioral observations; this was the last day that Erin, Dan, and Mary hauled cameras and tripods to their lek overlooks to film males and map their locations. We’ve collected what I think is a really exciting data set on our three focal leks this year, and it will be interesting to look at the data and see who the winners and losers are, and what makes them different.
With no more new data coming in, the crew are busy checking the data files against their field sheets to make sure we didn’t have any data entry errors. They have thousands of lines of data to go over- when they read it aloud they sound like auctioneers.
The free mornings also mean we can use the next few days to try to capture some more grouse. We spent the weekend installing and testing the drop net down at Monument Lek, and we finally had a chance to use it this morning. We awoke well before 4 to an unexpected half-inch of snow- fortunately not enough to delay our plans. We had the net set a little after 4:30, which ended up being pretty good timing as the birds started flying in by 4:45, when the sky was just starting to get light. The males and females did not seem too scared of the net. We waited until it was light enough to start identifying the males. Unfortunately the females started leaving the net area then, and dragged some of the males with them. We were finally left with three birds under the net, when a nervous one (“Picard”) decided to flush. Worried that we would lose all the birds if they all decided to fly way, we pulled the net. It dropped perfectly! We ended up with two juvenile males that we may be able to ID from video and buttprint data.


We are probably going to try again tomorrow on Monument in order to try to catch some adult males, then move the net to Chugwater before and try their before the crew leaves.

This happens every year out here. It seems like only a short time ago that we were unpacking all our gear and showing the crew the leks for the first time, yet here it is the last week in April and we are less than a week from bidding our assistants farewell. We only have a few days left to make the most of our season- after that, we will have to make the most of the data we did collect, and plan for next year.


The past week has been pivotal in terms of what the 2011 will give us. Some things worked, and some didn’t. One project that didn’t work, unfortunately, was the fembot. She worked very well in 2007, well enough in 2008, but this year most males were pretty aversive to her. While we did get some courtships, they will probably not be enough to make any generalizations about how male courtship behavior relates to other behaviors. Very disappointing, since this tool proved so useful in the past. We are thankful that we will have new, more realistic robots by next season. Possibly the most frustrating aspect of this is that we don’t know what has changed. Has the fembot aged in some way that makes her look dramatically different to the grouse, or do they behave that much differently in boom years compared to at lower population densities or after particularly harsh winters?

The playback experiments in which we broadcast alarm calls have in general been going much better. We have now completed at least one trial at each lek of each of three calls: Killdeer, Pronghorn, and Raven. Obviously final interpretation will have to wait until we quantify differences in behavior, but it looks like males respond little if at all to the Pronghorn, and most to the Raven. We probably won’t have time here to analyze all of the videos here, but the crew have been hard at work identifying all the males on the video so we can speed up the data collection once we get back.


Our experiment at Monument looked a little different yesterday- we had a couple inches of snow from a storm the night before. It was all gone very quickly though.

We also took a relatively calm afternoon to finish building our drop net. If all goes well we will have the last few days to set this up on each of the leks and try to catch some birds! We may not be able to match the measurements of birds we catch with the sounds and behaviors of this year (since this years’ ID’s are based on buttprints, and we may not be around long enough to see the males displaying again), but it will hopefully help us next year by giving us a few more banded birds to start with.

We’ve been collecting “background data” all season- measuring mating success, and getting sound recordings of displays and video tapes of natural courtship interactions and bouts of aggression. Every year we hope to pair these data with targeted experiments that will let us measure specific reactions of the males. We wait to do these until after the peak in breeding so as not to interfere with reproduction in this sensitive species, and because males may have their attention divided if lots of receptive females are nearby.

One of our goals is to measure environmental responsiveness of males- how quickly they notice important things in their environment, how dramatically they respond, and how soon they return to their normal behavior. After having trouble getting appropriate responses to objects, our last, best hope this year of measuring responsiveness was to play back the sounds of animals. We started with the alarm call of Killdeer- Gail got some killdeer recordings from the Borrer Lab at Ohio State University and edited them into a single playback file. We used the outdoor rock speakers from Jessica, placing three at each lek, and running the cable to the recording blind.

Fortunately these experiments appeared to work pretty well, although we will need to sift through the video tapes to quantitatively measure male reactions to the sounds. The males reacted, but not too much (i.e. they didn’t flush off the lek), and at least from the trials at Preacher it seemed like males were pretty consistent across trials. We are moving ahead with playbacks of two other local species: Raven and Pronghorn.

In the photo above, Gail is measuring the sound level of our playback so we can report how loud our playback was.



We are also prepping for the fembot experiments. We want to measure how males approach the robotic female, and how they adjust their courtship effort. This will give us a measure of social responsiveness. The questions are: is social responsiveness correlated with environmental responsiveness, and when we look at the relationship with mating success, do the males who mate the most share some level of responsiveness.

Setting up for the fembot experiment is quite a process. Once we’ve settled on the path she will take, we have to connect lengths of train tracks, then level them with bits of dirt or last year’s cowpies, polish off the tarnish to ensure good connection between the base of the fembot and the tracks, and pile up dirt along the sides to disguise the edges.







Once the tracks are set up we test the movement of the fembot to make sure she has a smooth ride!





Unfortunately our first couple of tests at Preacher have not gone terribly well. Hopefully we will have more success at Chugwater and Monument- these leks are much bigger, and therefore more critical in terms of measuring enough males for statistical analysis of the data.

It’s been more than a week since I posted the last update- this is due to 1) 12+ hour days with not much time for creative reflection, and 2) some inadvertent system updating caused us blow much of our monthly allotment of internet bandwidth. To quickly catch-up:
One of our goals this year is to measure how males vary in their environmental responsiveness, and how this relates to their social responsiveness and ultimately to their success on the lek. We’d planned to do a suite of 3 experiments testing different facets of responsiveness- sensitivity to acoustic cues, to food, and visually to novel objects. We tested the food and novel object protocols at a different lek (North Sand Gulch), and both failed spectacularly. For example, we set out an array of strawberries, tomatoes, and apples on the lek before dawn in hopes we could detect differences in how long it took males to approach the food, and how much they ate. Turns out the males (and females too) completely ignored the food. So plans change, as they often do in field biology, and we’re now hoping to do a more complex set of sound playbacks. We should start these soon, so I’ll have updates on those before too long.
I’ve managed another round of sound recording on all the leks except Preacher, where I will be tomorrow morning.
We are finally past the peak in breeding. The peak was fairly prolonged this year. Most years we have about a week and a half of intense activity, but it lasted 3 weeks or so on Chugwater and Monument. Now, for these two leks it was like a switch was flipped, and we’ve gone from long mornings with many females to empty leks by 8AM. As long as the birds don’t leave too early, this is actually good for our experiments, since the lack of female visitation means we won’t have to compete for the males attention as much.
Yesterday on Chugwater we had encounters with two different raptor species. First, at a little past 7, almost all the birds were scared off by a rough-legged hawk. Rough-leggeds are not much bigger (if at all) than a sage-grouse, and really have little chance to take down a male. This hawk made an attempt at the last guy on the lek, and swerved away at the last minute, I guess thinking better of it. The sage-grouse was not impressed.



We also had a small dark raptor zip through at sage-brush level. My first instinct was that it was a small falcon called a Merlin, but Dan noticed from the photos that it was actually a small forest accipiter called a Sharp-shinned hawk. We are miles from the nearest tree, so this was a big surprise for us!



Many busy days ahead with acoustic playbacks, and starting to set out the train tracks for our robot experiments.

Definitely worth staying up late for this. Normally we are heading pretty directly towards our bunks when the clock strikes 9PM, but yesterday we got back into our cold-weather gear and piled into the truck to head down to Monument Lek. As we approached we stopped every so often, intently scanned the sage with our spotlights, looking for males roosting near the lek. After passing through the lek proper, we headed up the two-track that emerges from the north edge of the lek. Around a bend, Erin spotted a bird maybe 75 feet from the road, in some short sage. Gail drove towards the bird, and I grabbed a long-handled net and walked beside the truck. When we got pretty close, I darted towards the bird and covered him with the net. Success!

We extracted the male from the nylon mesh of the net, and dropped him in a pillowcase while we got all the processing tools out. This guy, now #326, was weighed, and measured on his tarsus (leg), wing, culmen (bill), and tail. We also plucked one feather and got a small blood sample.



We also put on leg bands- we’re trying 3 spiral bands here on the right leg, but may go with two. (see above).

Since this guy was almost right on the lek, we decided not to put a radio on him- we already know where he was roosting, and one of our main goals with the radiotelemetry is to identify roost sites so we can be more efficient in locating new birds to catch at night.

Great start to the banding season- we’ve had many nights when we’ve spent hours and not seen a bird, so to have one on the first night feels like a good omen. The crew really enjoyed finally getting to see a bird in hand. There is nothing like getting to touch the bristly sound-producing feathers and the soft pliable skin over the vocal sacs. What cool, bizarre birds!