Impacto de peces herbívoros en macroalgas y el crecimiento de Poscillopora damicornis y Poscillopora capitata en la Isla de la Plata, Ecuador

摘要

Coral reefs are highly diverse and productive but threatened due to a myriad of anthropogenic factors and due to climatic variations. One issue of concern for coral survival is the proliferation of algae due to the elimination of grazers and nutrient runoff. Herbivory is a key ecological process in marine systems that keep algae under control. The purpose of my study was to study experimentally the impacts of herbivory on two species of corals Poscillopora capitata and Poscillopora damicornis and its associated communities. The experiment was conducted in La Plata Island, Ecuador. To estimate the impacts of fish on marine algae I placed settlement plates inside four treatments that consisted of total fences, partial fences and an open control plot that selectively restricted the access to different types of fish inside them with coral fragments each one and recorded the fences to quantify the diversity of fish and characterize their behavior around the experimental units. We found that grazers did not have any impact on the abundance of any functional groups of algae through time and space or any impact on species, richness, diversity and evenness of functional groups of algae but after a year, all the transplanted corals grow on average 40% in all treatments. I hypothesize that meso-consumer smaller than 2.5 cm could play a key role regulating algae.