KRISTINA PAXTON

I am interested in the underlying ecological and evolutionary causes and consequences of movement. Integrating both experimental and field observations, I study the links between individual behavior and physiology and spatial processes that influence populations and communities. Movement can profoundly influence both ecological and evolutionary processes, and the study of Movement Ecology is a rapidly growing field, contributing to timely issues including habitat fragmentation, biological invasions, climate change, and the spread of pests and diseases, all major threats to Hawaiian ecosystems. I have employed a suite of cutting edge technologies such as stable isotopes, high-resolution genetic markers, and automated radio telemetry to quantify movement, at both individual and population levels, to understand seasonal interactions, linking geographically separate areas connected by movement. The strength of my research program lies in the integration of movement patterns with measures of habitat quality, individual physiology, and fitness to understand the mechanisms affecting population dynamics.

I am currently developing a study to understand how movement of Hawaiian forest birds within a naturally fragmented landscape known as “kīpuka” influences song structure at both a population and individual level. The songs of Hawaiian forest birds are acquired by social learning, and the cultural transmission of acoustic traits, like genetic traits, may be influenced by fragmented landscapes if movement between habitat patches is limited. Using automated telemetry tracking and song recorders we will simultaneously examine movement and song patterns of four species of forest birds that have different propensities for movement and song complexity: `Apapane (Himatione sanguinea), Hawai`i `Amakihi (Hemignathus virens), `Ōma`o (Myadestes obscurus), and `I`iwi (Vestiaria coccinea). Forest birds within the kīpuka system have persisted in fragmented habitats for many decades. Therefore, the extent of movement (e.g., stay in the small fragments, move among the fragments, or change locations seasonally) in relation to habitat characteristics such as patch size, vegetation structure, and resource availability will provide important insights into ecological strategies used by forest birds to cope with fragmentation. Moreover, the degree of movement across the landscape may play a major role in structuring acoustic diversity within and among populations, which has important implications for gene flow and the connectivity of populations over time. Understanding the spatial patterns of forest bird movement in a fragmented landscape and potential impacts on the cultural transmission of song will be important for future management of Hawaiian forest birds as climate change models predict large shifts in the climatic space of animals in Hawai`​i, resulting not only in a loss of habitat for forest birds, but also fragmentation and isolation of remaining habitat. Project collaborators include: Dr. Pat Hart, University of Hawaii Hilo and Dr. Eben Paxton, USGS Pacific Island Ecosystems Research Center. This research will also provide opportunities for undergraduate students to gain hands-on experience in ecological research, and the integration of graduate student projects.