You are what you eat: diet quality, display behavior, and mating success in Greater Sage-Grouse

AOS Research Grant Seminar

Presenter: Eric Tymstra; Ph.D. candidate in the Graduate Group in Ecology at the University of California, Davis; 2020 Werner and Hildegard Hesse Research Grant winner

Greater Sage-Grouse males gather on leks each spring to perform energetically costly courtship displays, and only a few of them get most of the matings. But what determines which males succeed? In this talk, I bring together three parts of my dissertation. First, using more than a decade of data from leks in Wyoming and California, I show how lek size changes the path to mating success: showing up matters everywhere, but on larger leks a male’s position relative to copulation hotspots matters more. Second, using GPS-tagged males, I ask how foraging choices and sagebrush chemistry relate to display performance, and find that where a male forages matters more than which plants he browses once he’s there. Third, I evaluate a fecal biomarker of detoxification as a window into the physiological cost of eating toxic sagebrush, and what it can and can’t yet tell us about male performance. Together, these results show how social context, space, and diet interact to shape mating success, with implications for managing sagebrush habitat for sage-grouse conservation.