The only self-fertilizing vertebrate, the mangrove killifish, serves as an indicator of environmental pollution in disappearing wild mangrove habitat. The research will explore varying lengths of exposure to biologically and environmentally relevant levels of mixtures of insecticides, fungicides, and herbicides on aggressive behavior, contest dynamics, testosterone (T), and cortisol (F) in the mangrove killifish (K. marmoratus) utilizing a novel experimental approach analyzing flexibility in behavioral and hormonal response phenotypes. The research will be conducted in collaboration with Dr. Yuying Hsu of National Normal Taiwan University in Taipei, Taiwan. The Hsu lab houses captive populations of the mangrove killfish, offering a unique opportunity for international collaboration. The research augments dissertation research examining behavior and hormones in golf course living birds. Using the killifish as a model, the research in Taiwan will examine how pesticide mixtures commonly in use at this, and other, golf courses may influence behavior and hormones expanding upon my dissertation work. This research may inform on impacts (if any) of levels of contaminants currently thought to have minimal physiological impacts. Studying a unique species while fostering international collaboration with a world leader in scientific research will be valuable to my personal and professional development.
Genetic control with predictable relationships between aggressive behavior, testosterone, and cortisol regarding responses to conspecific conflict are well studied in the mangrove killifish. This provides valuable and difficult to achieve control of genetic variation, often thought responsible for individual variation in hormone-behavior relationships. The experimental design is unique, as fish will be exposed to environmentally relevant levels of a pesticide mixture. Exposure will occur for short (7 days) and long intervals (14 days); while traditional methodology typically uses shorter exposure periods this is unrealistic compared to what is experienced naturally. Measuring aggression, testosterone, and cortisol after exposure also deviates from traditional endpoints measured in laboratory contaminant studies. By utilizing novel animal models and toxicological endpoints, in concert with biological methodology, and accounting for synergistic impacts of multiple contaminants, a realistic perspective concerning sensitive impacts of contaminants on physiology and behavior is possible. Interdisciplinary approaches combining behavioral endocrinology and toxicology are necessary for understanding how contaminants may impact behavioral and hormonal profiles, and ultimately, the health of human and wildlife populations.
This award under the East Asia and Pacific Summer Institutes program supports summer research by a U.S. graduate student and is jointly funded by NSF and the Ministry of Science and Technology of Taiwan.
