What’s on the menu?

Monument Draw, between our camp and one of our leks. Sagebrush is definitely the dominant plant out here!

Our focus in our Sage-Grouse research has been fairly limited to the lek– this is still keeping us busy even after many years of study! However, it’s always nice to get a more comprehensive view of the ecology of whatever organism you are studying, and towards that end, we have initiated a collaboration with Dr. Jennifer Forbey from Boise State University. For the Sage-Grouse, their life revolves around the sage plants (genus Artemesia) that form most of their diet, especially in the fall and winter. Jen spent a few days with us a the end of March to see our site, tell us about her research on the interaction between sage and the animals that depend on it, and plan out the first steps in our research together.

What at first seems like a uniform world of “sage” out here turns out to be a variable landscape of food quality for the grouse. First of all there are different species of Artemesia. In our site we have at least two, the basin big sage and Wyoming big sage. These are usually pretty distinguishable, although sometimes smaller Basin plants can look like larger Wyoming plants. The leaves are usually pretty different though, as Jen demonstrated. Jen gave us a handy rule of thumb for this: you can remember the Wyoming sage is like a Wyoming native giving the middle finger to the Californians! We got a laugh out of that.

Sage-Grouse usually cut all but the base of the leaf.

Jen showed us how to distinguish foraging by different herbivores in the area. The grouse tend to pick just the leaves, so if you have a sharp eye you can find the remaining leaf base. Old foraging will show a brown scar in the middle of the leaf, but if you happen to find a place where they have been foraging during the past day or two it will be bright green. Rabbits, on the other hand, tend to cut the entire stem off in a neat angled cut. They harvest the leafy parts before the sage can mount an defense (see below).

Neat diagonal cut = rabbit

Sage stems harvested by rabbits.

The sage are full of all sorts of secondary chemicals such as phenols and terpenes, making them pretty unpalatable to most animals. Jen had us taste a leaf and those little things pack a punch, leaving a persistent bitter taste in our mouths.

The Sage-Grouse obviously have a way around this since they eat almost nothing but sage for months out of the year. One adaptation is a specialized gut with two large caeca (blind pouches coming off the intestine). These are places where bacteria can work their magic and help detoxify and digest the sage. On the lek you’ll often find a dark, gooey tar-like caecal casts left by the grouse, which look very different from their normal (goose-like) poop. I can’t believe I don’t have a photo at hand to show this!

It gets more interesting when you look at variation among plants of a species. While the Sage-Grouse can eat the sage, Jen’s work has shown they prefer to feed off of plants that have less of these secondary chemical compounds. Eating bad quality sage with too high a concentration of these means the grouse have to work harder at digesting for fewer nutrient rewards.

The sage plants themselves are not passive players in this. When something starts to damage the leaves of a sage plant, it will begin to produce more of these defensive chemicals. Even more impressive- as the volatile compounds reach the air, they can spread to nearby plants, causing neighboring bushes to ramp up their production of chemicals as well. What this means is that the longer Sage-Grouse spend foraging in a given patch of sage, the lower quality the food becomes.

Male sage-grouse leaves the lek

Male sage-grouse flying.

This chemical response by the sage may solve a mystery stemming from a 1980’s study of sage-grouse behavior from the Mono Basin in California. Sandy Vehrencamp and colleagues followed radio-tagged males and found that the “good” males (with high energy reserves) were actually traveling farther from the lek, while the males with poor reserves foraged close to the lek. It could be that the plants near the lek tend to build up more of these secondary compounds, so males that can travel farther may actually encounter better areas in which to feed. We hope to follow up on this possibility as we learn more about the way that off-lek foraging behavior interacts with on-lek courtship and performance.

Kiwi Commentary

It looks like the commentary that I wrote with Lauryn Benedict write is now online (it may require journal access- feel free to email me if you aren’t able to get it through your university’s network and would like a copy). Lauryn and I share a lot of the same pedigree: we were undergrads at Cornell, then jointly advised by Walt Koenig and Eileen Lacey at UC Berkeley for our PhDs . We even did our field research in the same place- the Hastings Natural History Reservation in Carmel Valley. Lauryn studied another one of those common but not terribly well known birds, the California Towhee.

It’s fun to get to write something up with a friend and colleague like this. Our manuscript puts some context around a paper on vocal behavior and duetting in a species of kiwi.

 

January 2013 presentations

Early January was pleasantly busy. It started with the SICB (Society for Integrative and Comparative Biology) meeting held in San Francisco. This was my first SICB, and I was really impressed. It was one of those meetings where you really learned a lot, whether it was cutting edge techniques or fascinating studies on all sorts of organisms (or, most likely, both at once). I’ve usually been to meetings that either focused on birds, or else more narrowly on the sorts of animals (fish, insects, birds, mammals) that are typically featured at animal behavior meetings. SICB really does have everything from fossils to enzyme activity in symbiotic bacteria to bird phylogeography. It’s also very student friendly- as much or moreso than Animal Behavior Society. I’ll heap on one more point of praise- the poster sessions were fairly well run, with plenty of space to get around. This is something almost every meeting does wrong by packing too many posters into to small a space.

 

I presented the more-or-less final version of the laterality study, and people seemed pretty interested in it.

 

Talking about grouse

I left SICB early to head down to Monterey where I was scheduled to speak to the Monterey Peninsula Audubon Society. This was a fun opportunity; one of my first public lectures as a graduate student was to this same group more than 10 years ago. I was reminiscing about that talk, and how that was in the era when people were starting to give Powerpoint presentations on the computer (rather than getting slides developed), but nobody actually had projectors yet. I showed up not knowing that if I wanted to give a talk from the computer I needed to bring my own projector! I managed to come up with an improvised solution- they did have a media projector that accepted composite input, and I happened to have a video camera from my field studies in my car, so I was able to film my laptop screen with a hi-8 camera. Not ideal, but better than not having any AV at all!

 

Maybe somewhat appropriately, we had a bit of a scramble to get the audio speakers set up this time around as well, but it all worked out. The audience seemed to enjoy the talk and especially the high speed video of the grouse displays. Folks kept me there for a long time with great questions, and apparently I was even on public access TV. I even got to meet the mother and father-in-law of Marc Dantzker, one of our collaborators.

 

Of course no trip to Monterey is complete without a stop at the Monterey Bay Aquarium. Even with the sea otter exhibit closed for construction and no mola mola in the big Outer Bay tank, it’s still a magical place to go. I’m sure I’m not alone in this thought: standing in the dark watching the jellyfish or big tuna tank is almost a religious experience.

Outer Bay Tank at Monterey Bay Aquarium

 

I’ve been to the aquarium several times, and each time there’s something new to see. I think my favorite part was getting an up close look at a Laysan Albatross that some handlers brought out in front of the kelp tank. I also had fun using my new macro lens to get photos of shorebirds in the aviary.

 

Laysan Albatross

Phalarope in Monterey Bay Aquarium

Although we missed up close looks at sea otters at the aquarium, we did see them several places along the coast there, including some really nice looks right by the wharf in downtown Monterey.

Sea Otter

Two big updates from the fall

The big updates from last quarter are probably the following:

1)   I survived teaching my first class- the 175-student Intro to Evolution course here in the Department of Evolution and Ecology at UC Davis. It was definitely a scramble to get the lectures put together each week, and I can see areas for improvement both for the course content and my teaching style, but all in all I think it went pretty well. At least no pitchforks and torches outside of my office, and reasonably good student evaluations- very few marks below average in any of the categories. Although it really is amazing how much time it takes to outline a lecture and craft a set of powerpoint slides, I enjoyed scouring the web for interesting class examples and media, and I liked the time in front of the class (at least most of the time- 7:30 AM could be rough if I didn’t sleep well or was up late putting the finishing touches on the lecture.

While I’m on this topic, a big thank you to my TAs David Luecke and Sarah Signor, as well as my graders Matt Meisner and Dena Grossenbacher. They did a fantastic job in spite of my having to learn everything from scratch my first time through as a full instructor. I’ve thanked them several times already, but can’t hurt to do it once more.

 

2)   Gail and I were awarded our second full National Science Foundation research grant on the sage-grouse system this fall! This proposal will fund another 3 years of field studies in Wyoming. The focus of this grant will be to learn more about the foraging ecology of the grouse, and how variation in energy acquisition and off-lek behavior relate to the courtship tactics available to a male while wooing females on the lek. It will extend our use of robots and sound recording by giving us a lot more information on what males are doing in the remaining 21 hours of the day when they aren’t fighting and strutting on the lek.

This project will also include both old and new collaborations. We are welcoming back John Burt (University of Washington) who was a key developer for most of our sound analysis scripts. In the past few years he has turned his attention to creating next-generation telemetry tags for use in animal behavior studies. These Encounternet tags can do amazing things like share interaction histories so when either of two animals gets near a receiving station, it will receive the data from both animals. The tags John is creating for us should have both gps logging capability as well as accelerometers to measure movements (this technology has already been used in other animal systems, such as the mountain lion study out of UC Santa Cruz). Our second collaborator is Jennifer Forbey from Boise State University. Jennifer studies the interactions between sage-grouse and their main food item- sage brush. She will be helping us study foraging success in the grouse, in particular by measuring the suite of secondary chemicals that sage plants produce.

Sage-grouse Cort Paper Out!

Jessica Blickley’s Conservation Biology paper on the impact of chronic anthropogenic noise on sage-grouse took over 18 months to go through review. Thankfully our more recent paper proceeded much more quickly, in fact, it just came out. May I present: Experimental Chronic Noise Is Related to Elevated Fecal Corticosteroid Metabolites in Lekking Male Greater Sage-Grouse (Centrocercus urophasianus). This is in the journal PLoS One (PLoS = Public Library of Science, one of the first Open Access journals that charge a bit more for publishing but make the content freely available to everyone). The paper asks whether we can detect differences in traces of stress hormones in the poop of grouse that were on leks exposed to chronic noise versus control leks without the extra noise. The answer is yes, but like many things in science, the answer becomes a bit more complicated when you look at the details, or try to figure out what the results you find actually mean. There was a difference in the average level of corticosterone metabolites, but this wasn’t diagnostic. Additionally, it didn’t matter how close to the speakers the poop (and presumably the males) was, so the differences were shared across the entire lek. Still, further evidence that noise impacts are serious business for birds like sage-grouse, and are something management plans may want to take into account.

Jessica has another paper that just came out- this as the product of a seminar she took a couple of years ago. She and her colleagues put together a survey of job ads and questionnaires of people in charge of hiring conservation professionals- both to try to decode what skills ads are really asking for, and also to identify skills that graduate students might not get in the course of a “normal” PhD (whatever that is). It should be a really useful paper, and I’ll be sure to add it to one of the resources pages here next time I update those. So check out: Graduate Student’s Guide to Necessary Skills for Nonacademic Conservation Careers in Conservation Biology.

We’ve made some progress on several other fronts as well. We’ve gotten several other papers submitted, including a detailed look at fighting dynamics in male sage-grouse that I believe is our first paper making use of the high-speed video of male behavior. Another project we’ve gotten off of our desks is a characterization of the mechanical sounds in the sage-grouse, lead-authored by former undergrad and technician Becca Koch (now in a PhD program at Auburn). Gail and I also contributed to a paper on the negative effects of necklace-style transmitters in male-sage-grouse that included the acoustic analysis of one collared male with odd sounding displays. We have a few other manuscripts perched like baby birds at the nest hole, waiting to take that brave leap into the wide world of academic publishing. We should have at least one more paper make that leap before the end of the year. Big thanks to Gail for using much of her sabbatical to contend with some of this.

In other news, teaching is still the big focus, although I can’t believe how quickly it has gone. Only 4 more lectures in the quarter! I’m done with my other lectures for the time being (my City College of San Francisco seminar was on the previous Friday), but I’ve got several lectures, seminars, and meetings lined up for early in the new year including.