First record of the sawspine dragonet, Diplogrammus infulatus Smith, 1963 (Actinopterygii: Perciformes: Callionymidae), from La Réunion, south-western Indian Ocean

The sawspine dragonet, Diplogrammus infulatus Smith, 1963, is recorded for the first time from La Réunion, south-western Indian Ocean; based on a specimen photographed at L’Ermitage les Bains, Saint Gilles les Bains on 12 February 2008. The specimen is described and compared with its congeners reported from the western Indian Ocean

The holothurian (Echinodermata) diversity of the Glorieuses Islands (Eparses Islands, France, Mozambique channel)

Glorieuses archipelago is one of the Eparses Islands, French islands scattered in the Mozambique Channel (Western Indian Ocean). These isolated coral islands, without permanent human population, are important to evaluate the evolution of biodiversity without direct anthropogenic influence. Among several aims, the program BioReCIE (Biodiversity, Resources and Conservation of Eparses Islands) was to complete the inventories of several groups including the holothurians (Echinodermata). In November 2012, a multidisciplinary team explored the reef slopes of the island by scuba diving down to 20 meters (10 sites), and the reef flats at low tide (12 sites) collecting specimens and taking photos for identification. The total holothurian richness was 20 species; 10 species were collected on the slopes and 15 on the reef flats. Given the limited number of sites studied, the occurrence of the different species in each class is presented as frequent, infrequent or rare. The commercial species Holothuria nobilis, Bohadschia atra and B. subrubra were frequent but illegal fisheries on holothurians are already occurring. Temporal comparisons at local and regional scales using the same methodology show that the diversity in Glorieuses is high and suggests that the biodiversity is increasing as we go from South to North in the Mozambique channel, as observed also for other taxa associated with coral reefs (fish and hard corals).

Coral reef monitoring in the Iles Eparses, Mozambique Channel (2011-2013)

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

World seas : an environmental evaluation. Vol. II : the Indian Ocean to the Pacific

In the South Indian Ocean, French territories include Reunion (Mascarene archipelago), Mayotte (Comoros archipelago) and the remote Iles Eparses in the Mozambique Channel (Glorieuses, Juan de Nova, Bassas da India, Europa), and Tromelin, North-East of Madagascar. Their coral reefs are varied, from 18 km2 of fringing reefs in Reunion to 1500 km2 of fringing, barrier and double barrier reefs in Mayotte, caye reefs in Glorieuses and Tromelin to atolls in Juan de Nova, Bassas da India and Europa. Pressures on them vary from 850,000 inhabitants in Reunion to no permanent inhabitants in Iles Eparses. Annual monitoring of Reunion and Mayotte shows a gradual decrease in coral cover and fish biomass, due to overfishing. Yet an exceptional biodiversity is recorded in Mayotte, mainly due to its geographical position at the center of the WIO coral triangle, and the variety of reef habitats. In the remote Iles Eparses, more recent monitoring showed a remarkable state of coral reefs and their exceptional fish biomass. These coral reefs are under human threats mainly due to coastal development and land-based pollution, except for Iles Eparses. Climate change has an impact through coral bleaching whose effects are stronger for reefs in the North of the Mozambique Channel. The impact of the 2016 bleaching event was variable on islands but most corals showed signs of resistance with a good recovery of coral colonies. In order to limit degradation and overexploitation of reef resources, national marine protected areas (MPAs) have been made in all French islands: 2007 in Reunion, 2010 in Mayotte, and 2012 in Glorieuses while all Iles Eparses have been under protection for more than 20 years. Despite this, Iles Eparses are beginning to suffer from illegal fishing, including collection of holothurians and perhaps shells, particularly since 2012. Long-term monitoring is essential to describe trends in coral communities in the context of increasing human impact and climate change

Assessing coral reef biodiversity at the Glorieuses Islands Marine Park (Scattered Islands, SW Indian Ocean) with identification of priority zones for conservation

International audienc

Multi-disciplinary approach for coral reef management in Eparses Islands, SWIO

International audienceOral presentation about Multi-disciplinary approach for coral reef management in Eparses Islands, SWIO in 12th International Coral Reef Symposiu