Saturday, 19 August 2017
Rabbit fish research at Denis island
Rabbitfish are the main targeted fish species of the artisanal fishery of Seychelles, consisting of approximately two-thirds of the total annual catch. They are herbivorous and have been shown to help keep reefs healthy by grazing on invasive algae. With such commercial and environmental importance, Ameer chose to dedicate his PhD research to investigating the role that rabbitfish play in a marine environment, and their contribution to the resilience of tropical coral reefs. His research is crucial to small island states like Seychelles, as these regions rely heavily on tourism and fisheries for sustenance.
Ameer is currently conducting research on Denis Island for the fourth part of his thesis. He is specifically investigating the diurnal home range of rabbitfish around Denis Island and what factors, including tidal phase, habitat type and complexity, influence their movements.
Photo (AEbrahim): Ameer conducting research in lagoon at Denis
Denis Island has two very distinct habitats: vast corals reefs and lush seagrass meadows. Research from other parts of the world is increasingly demonstrating that coastal habitats, such as coral reefs, do not function in isolation but rather as part of a larger habitat network. Other habitats such as seagrass meadows lie in close proximity to coral reefs, allowing for reef dwelling organisms and materials to travel among these habitats. Numerous species of commercially important herbivorous reef fish, such as rabbitfish, may frequent these habitats through diurnal and tidal fish migrations.
Accordingly, Ameer has dispersed 34 acoustic receivers encompassing the seagrass meadows and coral reefs in both shallow and deep water environments around Denis Island. Each receiver has a range of approximately 250m, allowing them to track the rabbitfish that Ameer has tagged using internal acoustic tags.
Photo (AEbrahim): Placement of acoustic tags
In many regions of the world, including Seychelles, connected habitats like seagrass meadows are often forgotten when it comes to conservation management. Therefore, this part of Ameer’s PhD will also assist in determining whether rabbitfish are frequenting different habitats such as seagrass meadows, thereby aiding conservation management efforts. Furthermore, his research will hopefully help cement future marine conservation management for the waters surrounding Denis Island. He is now in the process of collecting his data for this research.
Posted by GIF