Effects of elevated CO2 levels on Coryphopterus glaucofraenum response to injured conspecific chemical cues

Carbon dioxide levels in the ocean are predicted to double by the end of the century, making the marine environment more acidic than it is today. This study aimed to analyze whether increasing acidity affects antipredator survival behavior of the bridled goby, Coryphopterus glaucofraenum. A group of 10 adult gobies were treated with elevated CO2 levels, simulating predicted conditions by the year 2100, and another group of 10 were treated in present-day levels. Each group was exposed to the chemical cue of an injured conspecific, a predation chemical alarm signal, and the behavioral responses of each individual were recorded. The two groups were compared according to average time spent under shelter, number of feeding attempts, and amount of time spent motionless after exposure to cue. Overall, this experiment supported the hypothesis that gobies treated in acidified water would fail to fully exhibit such predator avoidance behaviors; gobies treated in elevated CO2 levels spent less time motionless after exposure to predation chemical cue. This study attempts to make important observations about the effect of environmental factors on fish behavior as well as far-reaching implications for the future survival of fish species and the stability of marine ecosystems as a whole.

This student research was retrieved from Physis: Journal of Marine Science XV (Spring 2014)19: 30-35 from CIEE Bonaire.