Publications des scientifiques de l'IRD

Chabanet Pascale, Bigot L., Nicet J. B., Durville P., Masse L., Mulochau T., Russo C., Tessier E., Obura D. (2016). Coral reef monitoring in the Iles Eparses, Mozambique Channel (2011-2013). Acta Oecologica, 72 (no spécial), p. 62-71. Îles Éparses (French Scattered Islands, SW Indian Ocean) as Reference Ecosystems for Environmental Research : International Coastal Symposium 2016, 14., Sydney (AUS), 2016/03/06-11. ISSN 1146-609X.

Titre du document
Coral reef monitoring in the Iles Eparses, Mozambique Channel (2011-2013)
Année de publication
2016
Type de document
Article référencé dans le Web of Science WOS:000371838600007
Auteurs
Chabanet Pascale, Bigot L., Nicet J. B., Durville P., Masse L., Mulochau T., Russo C., Tessier E., Obura D.
Source
Acta Oecologica, 2016, 72 (no spécial), p. 62-71 ISSN 1146-609X
Colloque
Îles Éparses (French Scattered Islands, SW Indian Ocean) as Reference Ecosystems for Environmental Research : International Coastal Symposium 2016, 14., Sydney (AUS), 2016/03/06-11
Monitoring of coral reefs has become a major tool for understanding how they are changing, and for managing them in a context of increasing degradation of coastal ecosystems. The Global Coral Reef Monitoring Network (GCRMN) has near-global coverage, but there are few remote sites free of direct human impact that can serve as reference sites. This study provides baseline data for the French Iles Eparses in the Mozambique Channel, Western Indian Ocean (WlO), whose coral reefs are little known owing to their limited accessibility, and have been free from fishing pressure for over 20 years. Surveys of coral reef health and fish community structure were undertaken at four of the islands (Europa, Bassas da India, Juan de Nova and Glorieuses) in 2011-2013. Monitoring was conducted using standardized GCRMN methods for benthos and fish communities, at the highest taxonomic level. Benthic cover showed a latitudinal gradient, with higher coral cover and conversely lower algae cover (60% and 14% respectively) in the south of the Mozambique Channel. This could be due to the geomorphology of the islands, the latitudinal temperature gradient, and/or the history of chronic stress and bleaching events during the last decades. Fish also showed a latitudinal gradient with higher diversity in the north, in a center of diversity for the western Indian Ocean already recognized for corals. An exceptional biomass fish was recorded (approximately 3500 kg/ha excluding sharks, compared to a maximum of 1400 kg/ha elsewhere in the WIO). The presence of large predators and sharks in all the islands as well as the absence of fleshy benthic algae were indicators of the good health of the reef systems. Nevertheless, these islands are beginning to experience illegal fishing, particularly in the north of the Mozambique Channel, demonstrating their vulnerability to exploitation and the need to protect them as reference sites for coral reef studies, including of climate change impacts, for the region and globally.
Plan de classement
Ecologie, systèmes aquatiques [036]
Description Géographique
OCEAN INDIEN OUEST ; MOZAMBIQUE CANAL ; EPARSES ILES
Localisation
Fonds IRD [F B010066287]
Identifiant IRD
fdi:010066287
Contact