Coral reef degradation severely impacts butterflyfish distribution on Heron Island reef flat
Bryanna Mariel Andrews and Alexa K Kownacki
University of California, USA
: J Mar Biol Oceanogr
Coral abundance and structure dictates the composition of reef ecosystems providing both shelter and food to reef fish. Butterflyfishes are among the most prevalent corallivorous fish on reefs and as such can depend solely or partially upon coral for food. Because of their wide abundance, butterflyfishesâ presence or absence functions as an indicator for overall reef health. Four species of butterflyfish-two obligate and two facultative corallivorous fish-were observed and tallied in the reef flat around Heron Island in Queensland, Australia along two transects in each a degraded and healthy habitat. The difference in coral coverage between the two habitats was found to be statistically significant with a p-value of 2.234 e-10. Principal Component Analysis revealed a shift of facultative butterflyfish toward the healthy habitat, with 77.5% of data explained by the relationship between locations and transect. Additionally, means extracted from log-transformed data suggest that the twelve percent decrease in live coral between transects of the healthy habitat resulted in a 50% loss of fish abundance regardless of feeding guild. This suggests that a minor loss of coral can cause a dramatic loss of fish abundance and diversity which has important implications in light of global warming studies.
Bryanna Mariel Andrews is currently an undergraduate student at the University of California, Davis in the Wildlife, Fish, and Conservation Biology department. Though young, she has led two independent research projects overseas in both Queensland, Australia and Monteverde, Costa Ricaon effects of climate change on biodiversity. She has also assisted with experimental infections of Chytridiomycosis on frogs as part of a larger study. She is in the process of publishing several papers, and plans to attend veterinary school in 2016.