Greater sage-grouse (Centrocercus urophasianus) are weird alien-birds that are emblematic of North America’s western states. They live in the sagebrush steppes: a unique and harsh desert whose beauty belies the harsh conditions that animals face. My research is broadly focused on sage-grouse behavior and conservation. My project is two-pronged: I investigate the link between behavior and diet (sage-grouse objectives) as well as how young people in social-ecological systems engage with science and gain environmental science agency (citizen science objectives). Field days are generally split between lek observations in the morning and either vegetation or citizen science work in the afternoon.
Greater sage-grouse in California’s eastern sierra are part of the genetically distinct bi-state population [1]. Every morning, each crew member goes to their assigned lek before first light to record behaviors, including strut rate (how often the males “dance”) and aggression. Fortunately for me and my crew, these birds have a penchant for lekking in remarkably beautiful areas. While on the lek, we record the presence and location of specific birds there by recognizing unique “buttprints”: the individual pattern of white-tipped feathers on the rumps of these birds. The naming process requires creativity and a willingness to see shapes in the butts of birds, a skill I wasn’t sure I’d learn in grad school, but boy, am I happy I did. Staring at bird butts all morning is fun—don’t get me wrong—but it is actually a critical part of my research.
Greater sage-grouse, a threatened species, have experienced long-term population declines and now occur in approximately 56% of their pre-settlement range [1,2]. These declines are largely due attributed to human-mediated loss and fragmentation of sagebrush habitats [3]. Understanding how sage-grouse use their habitat and how these decisions affect their reproductive success on leks is critical in guiding efforts to restore, maintain, and improve sage-grouse habitat. Despite being sagebrush specialists, sage-grouse must find specific plants with the highest nutrients and lowest toxins [4,5]. During the breeding season, displaying to females is extremely costly (using up to 4 times more energy than normal) for males, but higher display rates result in more copulation events [6]. Thus, these birds must balance the costs of displaying on leks, traveling to forage, and detoxification of chemically-defended food [4,7]. Given this, it is important to understand how sage-grouse and other herbivores afford energetic costs of reproduction when energy can also be devoted to finding and detoxifying food. My research aims to understand how sage-grouse balance the multitude of costs associated with the breeding season and how dietary quality affects habitat use and reproductive fitness.
To carry out my sage grouse objectives, I am tracking birds on the lek and recording breeding behaviors. Some of my birds also have GPS trackers on them, which allow me to follow them to their foraging and roosting sites. At these sites, I collect sagebrush and sage-grouse pellets (poop!). Sage-grouse are surprisingly picky eaters. Sometimes you will come to a sagebrush patch, and one sagebrush is totally destroyed while the others are completely left alone. Since sage-grouse are browsers (feeding on bushy vegetation), it is easy to see their bite marks on plants. One of my favorite things to do in the field is get on my hands and knees and crawl through the sagebrush while following grouse tracks, pellet piles, and browse marks to experience how the grouse see the world. I’m not weird. You’re weird.
Anyway….from the sagebrush samples, I will be able to determine the amount of toxins and proteins in the vegetation. Using the pellets collected at roosting, foraging, and lekking sites I will determine the amount of metabolites (chemicals) associated with detoxification of food [7] and stress. These chemical measurements will then be linked to individual male reproductive behavior and allow us to better understand how diet and habitat quality directly affect male behavior and thus reproductive success. But, in order to link habitat use to individual behaviors, I need accurate butt readings!
Now, you might be thinking: “Eric, you get to crawl around and look for poop and slightly nibbled sage…how could your life get any better?” First of all, great questions. Secondly…I get to share my science with young people! My passion for science is motivated by my own relationship with environmental science and enacting change through science. To this end, I am also working with young people in the Eastern Sierra to study how youth gain environmental science agency. To do this, I am working with middle and high school students in Bishop and Lee Vining, California. Students are designing their own questions about sage-grouse behavior and working with me to carry out independent research projects. Using camera-traps and my Zooniverse website, students classify camera traps images to monitor lek attendance. In the field, we are learning a variety of methods to measure ecological factors (i.e. vegetation height, anthropogenic sensory pollution, and predator abundance). Students will present their findings to local managers and working groups. Throughout the process, I am interviewing students to understand how their ideas about science, conservation, and their own role in their communities change in light of interacting with science and its power to affect change. My afternoons are filled with taking students out in to the field to look at goofy birds, pick up poop, and chase ravens. These times make me think about how we can use science to make the world a better place for our community and the organisms we share it with.
Every day I get home dead tired. I wake up the next day, smell the sage and the coffee, and I am ready to go again.
Working with young folks to study sage grouse and learn our place as scientists and community members (PC: Jen Metes)
Eric Tymstra is a third year PhD student in the Graduate Group in Ecology at UC Davis. When he isn’t out studying birds, you can find him in the gym, the kitchen, or out watching more birds and fly fishing. After graduate school, Eric plans to continue his work at the intersection of animal behavior, conservation, and citizen science.
[1] Schroeder, M.A. et al. (2004). Distribution of sage-grouse in North America. Condor, 106, 363–376.
[2] Connelly, J.W. and Braun, C.E. (1997). Long-term changes in sage grouse Centrocercus urophasianus populations in western North America. Wildlife Biology, 3, 229–234.
[3] Connelly, J.W. et al. (2004). Conservation assessment of greater sage-grouse and sagebrush habitats. Western Association of Fish and Wildlife Agencies.
[4] Frye, G.G. et al. (2013). Phytochemistry predicts habitat selection by an avian herbivore at multiple spatial scales. Ecology, 94, 308–314.
[5] Ulappa, A.C. (2011). Nutritional and chemical factors shaping diet selection for two sagebrush specialists: Pygmy rabbits and sage-grouse. Master’s thesis. Boise State University.
[6] Vehrencamp, S.L. et al. (1989). The energetic cost of display in male sage grouse. Animal Behaviour, 38, 885–896.
[7] Guglielmo, C.G. et al. (1996). Nutritional costs of a plant secondary metabolite explain selective foraging by ruffed grouse. Ecology, 77, 1103–1115.
Main photo: Gail Patricelli
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