Long-isolated island species may be unusually susceptible to pathogens due to the combined influences of a long history of evolution in a disease-impoverished environment and the genetic consequences of historically low population sizes. Except in Hawaii, little is known about the extent to which disease threatens avifauna on other isolated archipelagoes of the Pacific. The proposed project will employ a comparative framework (mainland vs. island) to examine several factors influencing disease susceptibility in a group of native South Pacific birds relative to non-native introduced species, which are presumed to be relatively resistant to disease.
This project will be of immediate conservation value in its assessment of pathogen prevalence in several Pacific islands and in characterizing the genetic variation with which certain threatened species can respond to current and future disease threats. If avian pathogens are less common on remote South Pacific islands than on the mainland, then the proposed system also provides a unique opportunity to understand how pathogens may constrain avian life history through their demands on immune investment. Results from this project will provide an important baseline with which to compare future parasite surveys and will lend context to the well-studied Hawaiian disease system: is Hawaii unique, or is it part of a larger Pacific system in which the introduction of parasites could have disastrous consequences?
