CARIBBEAN REEF SHARK DECLINE AND MESOPREDATOR RELEASE IN THE TROPICAL ATLANTIC

Abstract

Removal of apex predators has been demonstrated to have lasting negative effects on the community structure of many ecosystems in the form of trophic cascades, specifically through the release and resultant superabundance of mesopredators. Carcharhinid sharks such as Carcharhinus perezi (Caribbean Reef Shark) are important apex predators on coral reefs and have suffered massive population declines over the past century. In order to assess how C. perezi population density affects overall reef trophic structure, I surveyed fish biomass and biodiversity across six reef sites in the Turks and Caicos Islands. I found a significant negative correlation between mesopredator biomass and C. perezi sighting frequency. This suggests C. perezi plays an important regulatory role in maintaining healthy coral reef populations, and has important implications for reef conservation.