The humble rabbitfish – the unsuspecting pillar of our healthy coral reefs

In a previous issue I discussed the most crucial species of the artisanal fishery in the Seychelles- the rabbitfish. My PhD research focused on the distribution, movement patterns and feeding behaviour of these fish, and other vital fish species, such as surgeonfish and parrotfish.

Looking closely at distribution, I carried out intense fish and benthic surveys encompassing 24 reefs around the Inner Seychelles Islands. Three major findings were discovered. Firstly, it was revealed through scientific analysis that current Marine Protected Areas (MPAs) around the Inner Seychelles Islands are not working in improving the abundance and biomass of crucial fish species such as rabbitfish, parrotfish and surgeonfish. This may be caused by the lack of enforcement around the Islands.

Secondly, my results show that seagrass habitats are crucial nursery grounds to these species, particularly to rabbitfish. Unfortunately, seagrass habitats are often not considered when MPAs are being established.

Lastly, it was found that two species of rabbitfish (i.e. the white-spotted spinefoot, and the streamlined spinefoot) are vital species that are helping to remove invasive macroalgae from reefs. Macroalgae is quite destructive to reefs as it has shown to release chemicals that deter settlement of coral. Following major bleaching events in Seychelles, many of the coral reefs have been smothered in macroalgae.
In fact some reefs have seen increases of up to 40% in the span of 10 years.

Picture 1: Photo of a pristine coral reef taken on Denis Island, Seychelles
Picture 2: Photo of a coral reef that has been smothered by invasive macroalgae taken in the St. Anne Marine Park, Seychelles
Therefore, from my results, it can be inferred that these rabbitfish species are important contributors to coral reef resilience. Coral reefs are one of the main attractions to tourists when visiting tropical island destinations like Seychelles. Relevant authorities, therefore, must take the utmost responsibility in recognizing their importance and taking necessary steps to safeguard them for future generations to enjoy.
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