Marine Research

Our marine research programme utilises standard survey techniques to provide reliable information on the status of coral reefs and other associated tropical marine habitats. ReefDoctor’s marine research programme presently consists of the following:

Coral Reef Monitoring

ReefDoctor has been monitoring the status of the Bay of Ranobe’s coral reef system since 2003. The long term surveying programme monitors various environmental and ecological parameters across the bay to provide an assessment of the impacts of anthropogenic and natural pressures on coral reef health. In particular, a major threat to the integrity and survival of the bay’s coral reef that requires close monitoring is the shift from coral to algal dominance. This is occurring across many shallow reef areas within the lagoon as a result of sustained nutrient loading and over-fishing.
The surveys are conducted across five core sites and in two marine reserves. ReefDoctor has developed an Underwater Visual Census (UVC) methodology specifically for the Bay of Ranobe, adapted from those of CoReMo. Both members of ReefDoctor’s science team and trained interns and volunteers take part in SCUBA-based transect surveys, collecting data on the following:

  • Indicator Reef Fish. Surveys are conducted along belt transects to collect data on the abundance and size of specific fish species that have been selected for monitoring on the basis of their ecological and economic significance.
  • Benthic Composition. The Point Line Intercept (PIT) method is used to collect data on the percentage cover of live hard coral, bleached/dead coral, soft coral, macroalgae, rubble, sand etc.
  • Indicator Invertebrates. The abundances of specific invertebrates, that have been selected for monitoring on the basis of their ecological and economic significance (e.g. sea cucumbers, sea urchins, crown of thorns starfish, giant triton shells), are recorded along belt transects.

The collection and analysis of UVC data the long term enables ReefDoctor to monitor changes in the coral reef condition over time and ensure management decisions are scientifically well-informed. The impacts of marine protection can also be assessed by monitoring deviations from the marine reserves baseline data and from comparison with unprotected sites. The results of these surveys can also be fed back to government departments, relevant regional and international coral reef organisations, and also to the local community to help them better manage their bay’s coral reef resource.

Seagrass Surveys

Seagrass beds are ecological and economically valuable habitats. They act as an important foraging and nursery habitat for a large diversity of organisms, stabilize bottom sediments, act as hydrodynamic barriers reducing wave energy, and filter coastal waters of nutrients, contaminants and sediments. Seagrass meadows are also of particular importance to the Vezo communities as they provide the basis of the productivity of numerous subsistence fisheries, including turtles.
Unfortunately, due to their location on land-sea interface, seagrass beds are subject to many anthropogenic impacts including eutrophication, sedimentation, human development and fishing net trawling. ReefDoctor has implemented a seagrass surveying programme to map and assess the status of the seagrass beds in the bay, and monitor changes in their health; forming the crucial first steps towards their protection. As part of a new Darwin Initiative funded ReefDoctor project, we are aiming to create seagrass reserves, with zoning for strict protection and restricted use, to protect 10% of the total seagrass habitats in the Bay of Ranobe.