EAPSI: Investigating the behavioral and physical responses of the lemon damselfish to ocean acidification

Patton Britta W, State College PA

Investigators

Abstract

Approximately one quarter of atmospheric carbon dioxide (CO2) enters the ocean each year, reacting with water to cause ocean acidification. It has been shown that resulting increases in CO2 levels dramatically affect fish behavior and physiology, suggesting potentially dire consequences for ecosystem structure and human socioeconomic systems dependent on marine fisheries. Under the influence of elevated CO2, fish become attracted to predators instead of aversive of them, and homing behavior is disrupted among other effects. This project will investigate the capacity for fish to cope with increasing ocean acidification associated with climate change. This research will be conducted in collaboration with Dr. Phillip Munday, one of the first researchers to investigate the impacts of increasing ocean acidity on fish at James Cook University in Australia. The data will be collected at the Lizard Island Research Station on the Great Barrier Reef. While the results from these experiments are striking, it remains unknown whether fish have an adaptive capacity to contend with a gradual rate of ocean acidification; critical knowledge for developing management and mitigation strategies. This research will determine whether a slow increase in acidity over a six week period will induce a within-generation coping response to changing pH in the lemon damselfish, (Pomacentrus moluccensis). A combination of cognitive and morphological responses will be measured. First, cognitive impacts will be determined by means of a spatial learning task under different CO2 conditions. This will be complemented by physiological measures the gill. As gills are the direct interface between a fish and its environment, and are known to show plastic response to stress and acid conditions in freshwater, they are likely to be one of the first places a plastic phenotypic response to acidifying waters may occur. This NSF EAPSI award is funded in collaboration with the Australian Academy of Science.