Abstract Of My Smithsonian Research Proposal

I submitted my research proposal to the Smithsonian Tropical Research Institute today for a two week visit in May. Below is my 250 word Abstract for this work:

Parasites are known to be important regulators of energy flow through ecosystems, and also to affect the fitness of individuals. Monogenean trematodes of the genera Dactylogyrus and Gyrodactylus that live in hosts’ gills or on the skin have been shown to be harmful to a variety of fishes under laboratory, aquaculture and natural conditions. In this weakened condition hosts may also have diminished reproductive capacity, measured as smaller functional gonads, lowered gamete production or diminished sexual coloration phenotype. My proposal is to begin a research project on the possible influence of monogenean trematodes on a livebearing Poeciliid fish species, Brachyrhaphis episcopi, endemic to Panama. Previous research on this species conducted at the STRI has shown the species to have life-history responses to the presence or absence of larger piscivorous fishes. Twelve known sites with B. episcopi would be visited and 40 fish collected at each. Fish collected would be examined for how many skin and gill parasites they carry, and would also be examined to determine reproductive condition such as number of eyed embryos carried by adult females as a measure of possible influence of parasite load. This would address two linked hypotheses: one, that higher parasite load is linked to, and possibly causative of, lowered reproductive capacity; and two, that higher parasite loads would be found in host populations that live in environments without predatory fishes such as large characins. Any monogenean parasites found would likely be new species because of the tight co-evolution of these parasites and hosts.