The 2011 Ned K. Johnson Young Investigator Award goes to Dr. W. Alice Boyle for her exciting and original work on the evolution and ecology of migration in birds. In her short career, she has made significant contributions to our understanding of the evolution of long-distance and altitudinal migration. Dr. Boyle is a Research Associate in the Centre for Applied Conservation Biology, Department of Forest Sciences - University of British Columbia, British Columbia, Canada. She has held post-doctoral fellowships in the Department of Biology at the University of Western Ontario where she has worked with Dr. Chris Guglielmo and Dr. Ryan Norris, another Ned K. Johnson Award winner (2006).
During her PhD, Alice sought to understand the ecological and behavioral characteristics of tropical migrant species that made them the evolutionary precursors for long distance temperate migrants. She made huge progress in this area, elegantly testing long-standing hypotheses using extensive phylogenetic comparative analyses. She then conducted a series of detailed (and arduous) field studies in Costa Rica on altitudinal migration. It was in Costa Rica that she tested competing hypotheses about the ecological factors that contribute to the evolution of migration between high elevation breeding areas and low elevation non-breeding areas. Using artificial nests she was first able to rule out the hypothesis that high nest predation risk at low elevation leads to migration. What she found next was even more interesting. It had long been held that since most altitudinal migrants are frugivorous or nectarivorous, that their movements must track the availability of these foods. In a massive study of seasonal fruit production, she found that migrants leave high elevation sites in the rainy season despite there being greater food availability higher up than down slope. These findings led her to formulate the limited foraging opportunity hypothesis which posits the novel idea that severe multi-day rain events at high elevations can reduce foraging ability of birds, such that they have lower apparent food availability and migrate to avoid these bottlenecks. This new perspective was a major shift in thinking about tropical migration and foreshadows important consequences of climate change.
Dr. Boyle’s other studies have contributed solid support for the limited foraging opportunity hypothesis. While working in Costa Rica, Alice discovered that the White-ruffed Manakin (Corapipo altera) is a partial migrant (i.e. only some individuals in the population migrate), and that migration is sex and condition dependent (i.e. males and low condition individuals of both sexes are more likely to migrate). Her post-doctoral research has been directed at the ecological, behavioral and physiological mechanisms that maintain partial migration in this species. Alice learned a variety of new approaches, such as using physiology to understand condition-dependent behavior, and stable isotope analysis of claws to infer altitudinal movement history. Her first paper from this work definitively showed that that the arrival of major rainfall events causes the down-slope migration of Manakins, and that there are significant physiological costs to individuals that remain at high elevation. This study was published by and featured on the cover of the Proceedings of the Royal Society B. It also resulted in widespread press coverage in Science Now and the Canadian Broadcasting Corporation’s weekly national science radio show “Quirks and Quarks”. Results from the second part of her study were recently published in Biology Letters, and shows for the first time a direct fitness tradeoff between reproduction and migration in birds. Male Manikins that migrate down-slope in the rainy season pay a reproductive cost by losing their status at lekking logs. Males that remain at high elevation (and risk perishing) benefit by increasing their status at lekking logs, and attract and mate with more females. A third component of this work has also been recently published wherein she and her co-authors conducted a community-level test of the foraging limitation hypothesis (see Oikos 2011). Altogether these findings represent a major contribution by Alice to our understanding of the evolution of migration in birds.
This past spring, Boyle initiated a new collaboration with Dr. David Winkler at Cornell University to study interactions among migration arrival date, physiological condition, and reproductive performance in Tree Swallows (Tachycineta bicolor). She is using novel methods, such as magnetic resonance body composition analysis and plasma metabolites, to understand how arrival condition and severe weather events affect reproductive investment by adults and growth allocation in nestlings.
Dr. Boyle’s work integrates advances from the fields of ecology, physiology and behavior to answer evolutionary questions. Thus, her work is filled with strong empirical data that fit together into a theoretical context. Furthermore, there is a very real application of her findings. As climate changes, the incidence and severity of rainfall in tropics are predicted to change from current patterns. Since many altitudinal migrant birds are frugivorous, they are the major seed dispersers for woody plants in tropical communities. Changes in rains will likely alter the movements of these birds and change the ecosystem functions they serve. Her work will have far reaching implications for both basic and applied research in ornithology.
Dr. Boyle has already established a strong record of accomplishment and we expect that her reputation will continue to grow. The AOU believes Alice Boyle’s body of work exemplifies that of a promising researcher who skillfully uses birds to study important basic and applied questions in ecology and evolution and is therefore the recipient of the Ned K. Johnson Young Investigator Award.
Award criteria.—The Ned K. Johnson Young Investigator Award recognizes outstanding and promising work by a researcher early in her or his career in any field of ornithology. Candidates excel in research and show distinct promise for leadership in ornithology within and beyond North America. They must have received their doctorate within 5 years of being nominated, must not have received the award previously, and must be a member of the AOU at the time of nomination. The award, presented for the first time in 2005, consists of a framed certificate and an honorarium provided through a gift to the endowment of the AOU honoring Ned K. Johnson, a lifelong supporter and former president (1996–1998) of the AOU.