McGill University
M.Sc. candidate
Supervisor: Frederic Guichard
Matthieu Leray, Smithsonian Tropical Research Institute
Start: 2024-09-01

Project

Decapods mediate the response of Pocillopora corals to environmental conditions
Coral reefs cover just 0.1% of the Earth, yet they support approximately one third of all marine species. Regrettably, coral reefs are threatened by human activities including nutrient and sediment accumulation from agricultural runoff. Of the organisms that coral reefs support, invertebrate communities are among the most diverse and understudied. In the Tropical Eastern Pacific (TEP), certain decapod invertebrates clear sediments from coral surfaces and protect corals from predation. However, decapods’ effects on coral physiology under different environmental conditions remain unclear. On Panama’s TEP coast, I will examine decapods’ influence on coral physiology in areas with high versus minimal agricultural runoff. I will remove decapods from experimental coral colonies in both high and low runoff areas, leaving control colonies untouched. Under both levels of agricultural runoff, I expect that coral physiology (i.e., protein content, chlorophyl a & c2 content, zooxanthellae density) will be improved among corals with decapods in comparison to those without. Additionally, I predict that this difference will be more pronounced under high agricultural runoff, where corals likely depend more on decapods for sediment removal. This study will highlight how agricultural runoff may increase corals’ reliance on decapods to maintain their physiology. If corals are in fact more reliant on decapods under high agricultural runoff, then this should be incorporated into conservation policies: it highlights the need to protect decapods, particularly in human-modified environments.

Keywords

corals, invertebrates, decapods, agricultural runoff, sediment, symbiosis, physiology