Expedition to Comoros studies reef systems

The recent expedition of local marine conservation body WILDOCEANS and its partners into the Comoros, made possible by Critical Ecosystems Partnership Fund (CEPF), saw the first visual reef surveys conducted in the deeper habitats (the depth between 40m and 200m) of their waters.

These surveys made use of Remotely Operated Vehicle and Baited Remote Underwater Video equipment provided by The African Coelacanth Ecosystem Programme.

Members of the University of Comoros (Nirina Rasoanandrasana and two PHD students, Ali Ramadhoine and Youssouf Eddine), the Directorate of Fisheries (Ibrahim Mohamed-Toihir) and the University of Oxford (Dr Lucy Woodall) joined the expedition aboard the RV Angra Pequena, a 72ft research vessel, and actively participated in research work.

Left to right, scientists Ant Bernard (South African Institute for Aquatic Biodiversity), Melita Samoilys (Cordio) and Lucy Woodall (University of Oxford) planning the mesophotic reef surveys in Comoros. Pictures: Comores, WILDOCEANS and ACEP Expedition

Led by Dr Melita Samoilys, the team repeated shallow surveys (originally done by Cordio – Coastal Oceans Research and Development in the Indian Ocean – several years ago) around 3 islands, Anjouan, Grande Comore and Moheli, using scuba diving to compare the condition of the areas over time. This also allowed them to understand the difference between the shallow habitats and the deeper habitats they were exploring.

Symbiotic relationship

Moving from the shallow reefs to explore the biodiversity of the deeper reefs by ROV, the team found a shift from the hard corals, which depend on their relationship with photosynthesising algae, to soft corals that do not have a symbiotic relationship with light-dependent organisms. The deep reefs were richly covered by various species of sponges and soft corals, including large sea fans and black corals.

In general, the conditions of the deep reef habitats at Grande Comore and Anjouan islands were good but the very low numbers of fish were striking. The fishermen who joined the team to observe the deployment of equipment and surveys in action, also expressed concern about fish numbers and declines over the past decade. In contrast to the habitats at depth, the shallow reefs on these two islands showed signs of severe degradation, most likely due to bleaching and dynamite fishing. What was disturbing was the huge amount of plastic and general trash collecting on both shallow and deep reefs.

“The team was very encouraged when they arrived at the marine protected area at Moheli Island to find reefs in comparatively good condition. The shallow reefs had healthy, hard corals that appear to have escaped recent bleaching events that has impacted much of the Western Indian Ocean,” said WILDOCEANS Executive Director Dr Jean Harris.

 

A Moray Eel on a deep reef being cleaned by a cleaner shrimp. The Moray Eels were found to be invariably surrounded by orange split-fin fish that have previously only been seen in shallower waters in the Seychelles.

“On Moheli island, fish such as rock cods and potato bass, were relatively abundant compared to areas outside of the MPA, indicating that the marine protected area is having a positive impact”, said Director of Cordio East Africa, Dr Melita Samoilys.

Highlights of the expedition were engagements between the expedition team members and members of key organisations in the Comoros. A delegation from the University of Comoros, led by the Dean of Science Achmet Said, welcomed the vessel on arrival and an introductory session was held at the University to discuss the aims of the project. The local NGO UMAMA hosted a community meeting in the Sima village on Anjouan Island and AIDE hosted similar meetings on Grande Comore and Moheli Islands. These were attended by the mayors, fishers, fishery and conservation managers and tourism representatives. The purpose of the gatherings was to discuss the purpose and approach of the project, to share the first visuals of their deep marine environment, and to invite participation by local role-players.

Empower

Fishermen from Anjouan island being shown the BRUV equipment by Ibrahim Toiher (Directorate of Fisheries).

The Critical Ecosystem Partnership Fund (CEPF) is a joint initiative of l’Agence Française de Développement, Conservation International, the EU, the Global Environment Facility, the Government of Japan, the MacArthur Foundation and the World Bank. A fundamental goal is to ensure civil society is engaged in biodiversity conservation. CEPF through WILDOCEANS, set out to empower the Comoros Archipelago science fraternity to understand the nature and distribution of benthic ecosystems and the coral reefs, and how to protect them.

“Having multiple stakeholders on the research vessel allowed the benefits of the project to reach well beyond the WILDOCEANS team,” said Mhoumadi Soihibou, CEPF Representative in Comoros. “This project is an important contribution toward the collective efforts to protect the marine biodiversity of Comoros.”

Youth highlight the plight of our oceans

“Research is expensive and technically demanding requiring the involvement of a range of stakeholders. The Comoros Expedition was an example of International agencies, regional bodies, government agencies, NGOs and host country communities (the fisherfolk) putting their combined expertise together to undertake science to better sustainably manage the ocean,” said managing director of the South African Institute for Aquatic Biodiversity, Dr Angus Paterson.

“The Comoros team made the WILDOCEANS team feel beyond welcome and having them share their passion and beautiful marine environment with us was a true privilege,” said Dr Harris. “We look forward to working with them again when we visit again in 2019.”

The RV Angra Pequena docked safely back in Durban, South Africa on November 2.