Wildlife Conservation Society (WCS) in collaboration with Namena Divers completed a week long survey of the Namena Marine Reserve and adjacent reef systems in Kubulau District in Bua Province. The surveys are a part of assessments WCS is conducting throughout the Vatu-i-Ra Seascape to quantify the impact of Cyclone Winston on coral reefs and community fisheries resources.

The Namena Marine Reserve is part of a complex barrier reef system located south west of Savusavu Bay. It is also one of Fiji largest and longest protected reef systems known for crystal clear waters, vertical walls (drop-offs) with rich pelagic marine life such as schools of barracuda, sharks, mantas, trevallies, turtles, groupers and sea snakes. Divers from all over the world flock to Namena to dive with the colourful marine life, including soft corals, hard corals, sea fans and other invertebrates.

This is the second barrier reef I have dived on in three weeks. Both Namena and Vatu-i-Ra were badly hit by the catastrophic cyclone, but there were differences in the intensity and scale of the impact. We witnessed more damage to corals and the reef structure in Vatu-i-Ra suggesting it received more wave energy, especially close to shore. The vertical walls and drop-offs at Namena were less impacted. Our surveys found 40-60% coral mortality in Namena, compared to 60-80% in Vatu-i-Ra.

The fish population at Vatu-i-Ra was also much lower, reflecting the damage sustained to the coral reefs. Corals provide home and shelter for many fish species, and without this, there is less places for reef fish, making them vulnerable to predators. While the fish population at Namena has decreased from previous surveys, we did document herbivorous (algae-feeding) fish nibbling algae creating a clean surface for new corals to settle on, which overtime will help rebuild coral communities.

I have also been documenting how Fiji’s reef systems are affected by coral bleaching. Approximately 20% of corals in Namena showed signs of active bleaching while corals in Vatu-i-Ra had less than 10% bleaching. There were signs of other stresses such as sediment damage, predation and coral disease at both Namena and Vatu-i-Ra.

It is clear from the surveys we have completed in Ra and now Bua Province, that the reefs have sustained significant damage, which will impact our inshore fisheries over the next 2-3 years. We will need to give our reef systems enough time to recover to be able to flourish, so that they can continue to provide “fish for the future”.