In 2019, our lab and Trevor Hefley in Statistics were funded from NSF to study the population biology of grassland birds at the Konza Prairie. This effort integrates our individual-level physiological data, population demographic studies, movement data, and the long-term survey data to understand the relative importance of local factors vs. regional and continental factors in shaping the abundance of this declining guild, and disentangle the direct and indirect effects of precipitation on this systems.
We collected our first summer’s data in 2019 and hope that the global pandemic does not completely ruin our chances of collecting at least the banding and resighting data so crucial to demographic studies. This project builds on related research ongoing since 2013 but adds two additional species to our project. We are now focusing on three core grassland-dependent songbirds for individual-level and population-level studies (Grasshopper Sparrow, Dickcissel, and Eastern Meadowlark). Additionally, we will model the responses of the broader community in some of our analyses. Graduate students Katy Silber and Dylan Smith (Boyle lab) and Meenu Mohankumar (Hefley lab) are all involved in this project.
We are extremely grateful for support from the National Science Foundation (DEB-1754491) that makes this research possible.
Too little rain is a serious problem; consequently, the morphology and behavior of animals inhabiting arid regions is often defined by coping mechanism for low precipitation. But does enough rain eventually become too much rain? Read our recent conceptual synthesis and review on Hygric Niches for Tropical Endotherms or check out this introductory explainer video.
Mounting evidence from the tropics suggests that at the wet end of the spectrum, higher-than-average rainfall may decrease fitness. Using seven years of capture data from a community of birds in the mountains of Costa Rica, we showed that a wetter-than-average year can be negatively associated with apparent survival, but the responses are species-specific… not all birds respond to rainfall variation in the same ways, even in the same communities. We are testing multiple predictions of this hypothesis in our tropical system working in multiple populations of Corapipo altera across precipitation gradients on both the Caribbean and Pacific slope. Elsie Shogren conducted population-intensive studies of social stability and individual condition at Volcán Tenorio National park (in some of the driest Caribbean-slope forests inhabited by White-ruffed Manakins) while past work has also taken place at El Copal, a private reserve in the Reventazón valley and Rara Avis where Alice did her PhD work. We have collected data from five additional populations elsewhere in Costa Rica, adding tests of genomic predictions to this study.
Additionally, this question underlies some of our collaborative work with members of the Manakin Genomics Research Collaboration Network.