Light and Temperature on Reef Herbivory
Effects of algal growth conditions on grazing intensity by juvenile and adult sea hares
Herbivore-algae interactions play a dominant role in reef health and stability. As climate change progresses, light exposure and sea surface temperature are predicted to increase. This study examines how herbivores respond to climate change-induced impacts on prey algae using the spotted sea hare (Aplysia dactylomela) and the red alga Laurencia intricata. Algae was cultured under increased light and temperature treatments then presented to adult and juvenile sea hares. The mass of algae consumed from each treatment by each age group was determined. It was found that algae grown under high temperature was eaten significantly less than algae grown of any other treatment. Adult sea hares ate significantly more per capita than juveniles and treatment preference was not significantly different between the two age groups. These results indicate that increasing sea surface temperature will likely have an impact on reef herbivory and macroalgal abundance and merits further study.