2015 Field Recap Part 2: Research

As I mentioned in the last post, things seem to be looking up for the sage-grouse. So what about our research?

Lots of sage-grouse watching again this year

A burrowing owl looks in on the sage-grouse lek

We stuck with the same two focal leks that we used last year, Chugwater and Cottontail. Basic monitoring went well, especially with the increasing number of banded birds making it a little easier to get ID’s on the lek, especially in windy weather. We came back with a great set of video and audio data. What is particularly nice is that we can now look at lekking behavior in an increasing population. We now have a lot of recordings from “bad” years in which the population was declining, so seeing how hard males work and what females do in a “good” year, a year with lots of young males on the lek and possibly better overwinter survival, could make a nice contrast when we start to examine the long-term trends in display and mate choice.

The first of our main goals was to continue with our robot experiments. This year, our goal was to try the “outside option” experiment again. We first tried this in 2013, but our additional robots “Salt” and “Pepa” were not constructed until fairly late in the season that year. We started a few trials, but the males were already winding down their display effort and were not responsive enough to warrant trying a new series. Turn to 2015, and we now have our robots ready! Credit to Anna Perry, who devised the first protocol, Ryane, who took the reins this year as experiment planner and main robot director, and of course Gail who put the robots together and has been working with robot birds for a long time.

So what was the experiment? Briefly, there’s a principal from the economic literature that while negotiations and haggling often occur in one-on-one situations, the broader market includes lots of different options and competitors for both buyers and sellers, and the presence of these “outside options” can make a big difference in the decisions that are made in the market. In particular, if a seller is engaging with one buyer who is not terribly eager to buy, the seller might benefit from switching to a new buyer, but only if the new buyer seems more profitable or eager than the original trading partner.

We wanted to test this with the sage-grouse, using two fembots as potential “buyers”, and treating the male sage-grouse as sellers. We were able to get trials on each lek where the outside option was either “interested” or “disinterested”. We also ran control trials throughout the season with only a single robot- these will help us correct for seasonal changes in how hard the males work (they seem to get tired towards the end of the season).

A successful night

Our second main goal was to gather a lot of movement and foraging data, so we can uncover the feedbacks between on-lek display behavior and off-lek foraging behavior of the males. This was moderately successful. The first step was catching males and putting on encounternet transmitters. These are small solar-powered devices that can log both where the male is and also capture data about how it is moving it’s body. We managed to get around 20 tags deployed, although we were hoping for more. The tall grass, while great for the birds in providing cover from predators, may have made it more difficult to see the eyeshine at night during our spotlighting forays. Additionally, the age ratio of the growing population meant there were more young males to be caught, and not all of those males set up territories on the lek.

Downloading encounternet data

All in all, we collected tracking data from 7 males, which when combined with the 4 males from last year, should give us a good picture of where males go off the lek and how they spend their time. For these 7 males, we used the positional GPS data to go out and find their foraging and roosting spots, and measure aspects of the habitat at these locations to learn more about how male sage-grouse use the landscape. We also took small clippings of the sagebrush to see how selective they might be in what they are eating.

One new pilot project this year, we collected some poop from the leks to check for the presence of a certain type of gut parasite called coccidia. If sage-grouse have a lot of it, it could be an important factor in explaining differences in behavior. There’s also the possibility that the toxins in the sage are strong enough to limit this type of parasite. Dr. Rich Buchholz at the University of Mississippi has agreed to look through our samples and give us an idea of what we are working with.

Many thanks to our crew this year Amber, John, Miles, McKinzie, and Kelly for their help this year! Also thanks for the help from the Boise State crew, in particular Chelsea and Marcella who stayed at Chicken Camp for several weeks helping catch birds and organize the vegetation sampling. Also thanks to Sue Oberlie (BLM) and Stan Harter (WyoG&F) for local institutional support and a number of people who stepped in once to help capture sage-grouse. We couldn’t have done it without you all!

The 2015 Crew

In the next post I’ll talk about outreach and other odds and ends of the season.

2015 Field Recap Part 1

I’m not going to lie– as much as I enjoy Wyoming, it was really nice to roll down from the Sierras and be greeted by the golden hills of drought-stricken California. It was a good but exhausting season with very little opportunity for diversion or reflection. Now that I’m getting settled back in my office, I finally have a chance to summarize what the last 2+ months of Chicken Camp have yielded.

LOTS OF GROUSE, LOTS OF RAIN!

Counting Chickens

The dry conditions in the West had not done the sage-grouse any favors, and over the past seven plus years we had watched the leks in the Hudson area shrink each season. Last year was a mixed bag, with some leks up in numbers and some leks down (and one lek, Preacher Lek, completely empty of birds on all of our counts). In 2015, were we finally turning the corner? Was the population cycle finally finding it’s upstroke?

 

It was with trepidation that we watched the trends in lek attendance this year. Thankfully, the numbers tell a much rosier tale this time around. All of our medium and large-sized leks showed strong increases. Cottontail Lek, once the monster lek in the area, last year was below 50 males, and this year was close to 80.  Similarly, Chugwater peaked over 30 males, while last year it hovered in the low 20’s. Monument, our original focal lek and site of our first array recordings and robot experiments in the “golden days” of 2006-2008, was up to the mid 20’s, although most of the birds were still out in the sage rather than readily observable in the main clearing. The two smallest leks last year, Coal Mine Draw and Ballinger Draw, were even or down a little, and Preacher remained empty. If I had to take a message from this, I’d guess all leks are not equally efficient at recruiting new males, and that small leks have a harder time recovering their numbers.

The upper display area at Cottontail, with the Wind River Range in the background

Regardless, our focal leks were filling up again, in large part with younger males in their first season of display. In our years of monitoring both Cottontail and Chugwater, we had come to anticipate where the cluster of top males typically hangs out. We were a bit surprised when our early-season numbers on these leks continued to grow, and males started showing up in unexpected places.  This was particularly true at Cottontail, where our main clearing filled out with males for another 100 or more meters. Most of the mating action was still in where we thought it was going to be, although the females would often wander far off camera before coming back and doing their business.

Male sage-grouse hanging out well outside the gridded area at Cottontail.

And the future? Obviously a lot can happen between now and next spring, but we are cautiously optimistic that we will see another bump up in numbers next year. There was more standing grass this year than we’d ever seen, and that should be good for hiding the females’ nests This spring we got a lot of moisture- checking a weather website we’ve gotten almost 7 inches of precip this spring, almost twice the 4 inches that’s average for the region. Through most of April the storms came through at even and well-spaced intervals, keeping things green. We did get some intense rain just before leaving, but the hope is that a green landscape will result in good quality plant forage and lots of insects that provide protein for the growing chicks. Healthy chicks should have a better chance of surviving the winter and showing up on the leks the next year.  And perhaps all the grass this year will also mean good nest cover next breeding season as well.

Rain means green!

The moisture meant it was a pretty good wildflower year as well!

Not as nice for wrapping up the field work though.

End of season mud

But for this year, more males meant more data!  I’ll have an update on our research activities in the next post. More birds* is definitely, erm… good for the birds too, especially on the eve of their potential listing under the Endangered Species Act.

*Anecdotally numbers seem up throughout the region too!

The Sagebrush Sea

We are back from our field season in Wyoming! I’ll recap our season soon, but first wanted to post an announcement for a great PBS Nature program airing this week. The Cornell Laboratory of Ornithology produced a beautiful film about the sagebrush ecosystem called The Sagebrush Sea. Much of it was filmed in west-central Wyoming near our field site (although I’m not sure any shots from the Hudson area made it in the final cut). One of the producers is Marc Danztker, a collaborator who got his PhD with long-time sage-grouse biologist and eminent behavioral ecologist Dr. Jack Bradbury. It was Marc who first set up a microphone array on a sage-grouse lek– he did so in order to measure the odd acoustic directionality of some parts of the sage-grouse display.

The crew of "The Sagebrush Sea" visit chicken camp (2014)

The program got a write-up on the Nature Conservancy’s blog Cool Green Science, written by none other than Lander biologist Holly Copeland. Holly has become a great friend to Chicken Camp. She and her husband both came out to help trap sage-grouse, and they’ve hosted our entire crew for a bbq for the past few years. Holly also does important work on land-use issues related to the sage-grouse and is currently on Wyoming’s Sage Grouse Implementation Team tasked with revising sage-grouse protections using the best science available to help keep the birds’ populations as strong as possible and off of the endangered species list.

 

Banded birds return! 2015 Field Season

In spite of the painful adjustment to getting up hours before sunrise, the past few days have been a fun introduction to the world of the lek. At this point in the season, one of our highest priorities is to get photographs of the males’ tails during display- we use these to help identify each male based on the spot pattern (we call them “buttprints”). We recognize these patterns from our distant overlook hills with a good spotting scope*, and it is possible to get pictures of these with a point and shoot camera or cell phone using the scope. However, we typically take the photos from much closer. It is easiest to do this from the edge of the lek, which means relatively close encounters with the birds. Even our technician who has worked with sage-grouse before hasn’t gotten to see the lek behavior up close, so watching the struts and fights, hearing the grunts, pops whistles, and swishes, is a real treat.

Male helpfully displaying his bands from atop an anthill

Sage-grouse, like most birds, molt their feathers at least once per year. What this means for us is that the buttprint patters we use are only valid for one season, and the next year when the male shows up on the lek, he will have an entirely new pattern. Fortunately, our increased attention to catching and banding the males means we are starting to be able to follow males across years as well. For example, we caught one male “Steve”** in his first year on Chugwater, watched him establish his territory and return for several years, all apparently without mating with a female. This year we’ve had a good number of returnees already from last year’s captures, including males on both Chugwater and Cottontail that yielded a lot of behavioral data last year.

Encounternet male leaving lek

Encounternet male leaving lek- note the antenna extending from his lower back.

While we have had good success finding banded males, our resighting of birds with radiotags seemed less encouraging at first. Several encounternet birds returned but did not seem to have tags, and we were worried that our Teflon harnesses might be prone to falling off sometime during the off season. Eventually we got close up photos during the process of taking pictures for buttprints, and started seeing the antennas sticking out. The good news is the harnesses are still on, and that the males survived and are behaving completely normally. If there’s a cause for concern, it is that after molt, the feathers on the back are going to impair the solar charging of the tag. New tags we put out this spring will work fine this spring, but maybe not as well for subsequent years on the bird unless we can capture the bird again and tuck some feathers under the harness.

Along with identifying the birds, we are moving forward with data collection. If buttprints are Step 1, then getting the grid of survey stakes is Step 2. As the weather warmed and the snow melted, it was easier to get to Chugwater Lek, so that was our first target. The key is not only to get the uniform 10m spacing of stakes, but also to make sure the stakes are arranged in a way that makes hill observation and data collection from the video as easy as possible. Once we get the first square as square as possible, then it is easy to build out from that by sighting along the rows of stakes, checking 10m spacings as we go. Chugwater always seems to be really muddy when we lay out the stakes. The road to Cottontail was pretty bad, and we didn’t make it down until yesterday. Cottontail Lek is much bigger, and we ended up with probably ~100 stakes in the grid there!

Cottontail, now with grid!

Finally, the crew is starting to get used to the spatial mapping of the birds. We all went up to the Chugwater overlook once the grid was up to practice. Our “base” data collection is therefore in place- pretty happy to have that done relatively early in the season. Next up will be setting up the microphone arrays, capturing some birds and getting the position and movement data from encounternet, and hopefully some early-season robot experiments to form the basis for understanding seasonal changes in effort.

Chugwater hill blind at dawn, waiting for the stakes and birds to become visible.

Chugwater Lek view from the overlook hill

* We have had very good luck with Alpen brand scopes. Very nice quality for the price.

** In the field, we name birds based on their tail feather patterns, or other silly names. This seems to make learning the birds much easier on the field technicians. When our undergraduates collect behavior data back in the lab, we only refer to them by their number, so there’s no chance of biasing our data collection based on the name the male was given. Also, we have not seen Steve yet this year.

First Days: 2015 Field Season

Welcome to Wyoming! Mwuahahaha

In spite of some snow and one of the coldest periods we can remember, things are getting going! Our crew, or at least most of them are here, and we’ve now been out to see the grouse two days in a row.

It took a couple of days, but four of our five technicians are here now. Arrival day coincided with the most recent winter storm, so one tech didn’t make it until a day later than the others (no big deal in the name of safety). The 5th technician? Well, that is another story. We’ve had people withdraw from the project before, sometimes for personal reasons, sometimes to pursue other career opportunities. It’s always a bummer when someone breaks their commitment to join us in Lander, but at least they’ve usually given us some advanced notice so we can find a replacement. Until now… Tech # 5, who was himself a replacement for someone else who withdrew back in January, let us know just a few days before the start of the season that he wasn’t going to make it!

When Gail and I stopped seeing red, we posted a quick request for a replacement on social media. We got a great response- strong applications from all over the country, and their references were similarly quick to get back to us or willing to spend a few minutes over the phone to discuss the candidates. Miraculously, three days after we sent out the request, we made an offer to our top candidate and that offer was accepted! We will be at full strength next week. I feel like modern-technology is a double-edged sword for us with regard to hiring and retaining our crew- it seems a lot easier now than it did even 6 years ago for people to continue to prospect for new jobs, but at the same time when we need to fill a vacancy ASAP, it sure is nice to be able to spread the word so quickly without having to formally post an advertisement and deal with the dozens of responses like we do in the fall. A big thank you again to all those who helped us get the word out.

First sage-grouse of the season! Right where they are supposed to be on Chugwater Lek.

Back to Chicken Camp. The crew’s first morning here was well down the minus side of the Fahrenheit scale. Chances of sage-grouse doing much interesting was pretty low, and chance of misery on our part was pretty high, so we delayed our first visit to the leks until yesterday. We drove out towards Chugwater and were rewarded with 6 males visible. We parked along the road and checked them out in the scopes for a while, then headed past the lek and visited a neat badlands area. The crenulated landscape was particularly beautiful with the few inches of snow.  All in all a nice morning.

Today we got into some proper grousing. Ryane and Amber set up a blind on Chugwater Lek while I took the rest of the crew up to our overlook hill. It was quite a bit warmer than yesterday, and really one of the most stunning combinations sunrise and moon-set that one could ever see. (Regular readers will remember that I get really excited over the full moon here). We saw 10 male grouse on or near the lek. They all hunkered at some point, implicating a nearby predator of some kind, but it wasn’t until about 6:30 that a Golden Eagle flew high over the lek and scared the birds away. We waited to see if the birds would return, and for the moon to finish setting, but were out of there pretty early by sage-grouse standards. An entirely beautiful and pleasant morning!

We’ve even managed to have a crew birthday already! I think the blue frosting was even bluer in person.