Inventory and Spatial Assemblage Study of Reef Fish in the Area of Andavadoaka, South-West Madagascar (Western Indian Ocean)

This study represents the first qualitative census of the reef fish assemblage of coral reefs in the vicinity of Andavadoaka, south-west Madagascar. Observational data of fish species sightings were collected over the course of a year, while visual census data, with low observer bias, detailing fish assemblage from the four major reef zones of the area were collected in a shorter 5-week period. A total of three hundred and thirty four (334) species from 58 families were recorded throughout the year, while one hundred and eighty seven (187) species were observed during the shorter assemblage study. The trophic habits of the fish population are comparable with other sites in the Western Indian Ocean, and suggest a healthy fish community, despite evidence of broad-scale damage from coral bleaching and associated mortality. The authors suggest that this can be explained by current relatively low levels of anthropogenic impacts from fishing. However, given the extent of regional reef degradation, fish species diversity may now be particularly vulnerable to future anthropogenic or climatic disturbances, such as increased fishing effort or renewed coral bleaching episodes.