Following severe cyclones, dead coral skeletons are rapidly covered by seaweed. High levels of seaweed can be harmful to coral reefs as it grows much faster than coral and many species contain toxic chemicals. It can also have a smothering effect, blocking out sunlight. However, herbivorous fish that eat seaweed help keep it in check. Not all herbivores are the same though, as some fish species eat only certain seaweed types. See goby gardening.
Andy is focusing specifically on the impact of Cyclone Nathan (March 2015). Taking note of fish size, species type and species numbers before and after the impact, he is determining whether there is any significant change.
Preliminary results indicate that some herbivores actually increase in numbers following cyclones, possibly due to increase in the abundance and diversity of seaweeds that offer a plentiful food supply. To learn more about the intricate relationship between coral, seaweed and fish, check out this article. (PDF)
Andy was awarded our 2013 Isobel Bennett Marine Biology Fellowship. He has also contributed to important Lizard Island research on indirect benefits of high coral cover and how apex predators suppress herbivore foraging on coral reefs (PDF).