Testing links among eutrophication, bloom algae, and green turtle fibropapillomatosis

Abstract

Fibropapillomatosis (FP) is a tumor forming disease which poses a major threat to green turtles (Chelonia mydas). Increasing evidence suggests that FP results from the proliferative growth of the herpes virus. Hawaiian green turtles have shifted their diet from native to alien invasive algae, especially in regions with high anthropogenic impacts result in blooms of these invasive species. Some invasive algae appear to store excess nitrogen as arginine, which is an essential component of envelope for this virus. Growth experiments of algae with nutrient enrichment and tissue analyses for field collected algae indicated that excess nutrient input can increase algal growth rates, and algal tissue arginine levels are higher in eutrophic regions than from tissues collected in less impacted regions. Thus, anthropogenic land-based sources of pollution such as elevated nutrient inputs appear to negatively impact marine hervibores by stimulating a nutrient storage metabolism of bloom species of marine plants.