Fiji is known for its underwater “beauty” and the Vatu-i-Ra seascape is the “house” for it. A number of popular dive destinations, such as the Namena Marine Reserve and Vatu-i-Ra reef are within the seascape. However, the Vatu-i-Ra seascape in not just a dive destination, the seascape holds Fiji’s highest diversity of marine organisms (reef and pelagic fishes, invertebrates, coral reefs and marine mammals).

Although a healthy system, coral reefs within the Vatu-i-Ra seascape are often exposed to disturbance from climate related (temperature related bleaching, cyclone damage, outbreak of predators, such as crown-of thorn starfish) and human induced (overfishing, unsustainable fishing and land use practices) impacts. More recently, there has been growing concerns about coral disease as a likely growing threat to Fiji’s coral reefs. Despite extensive applied research by government, academic institutions and non-government organizations in Fiji, there is no existing documentation on the distribution and prevalence of coral diseases.

In September 2013, “snapshot” surveys were conducted at six locations to assess distribution, diversity and prevalence of coral diseases within the Vatu-i-Ra seascape.

Above: Locations were coral disease assessment surveys were conducted

Left: Yashika Nand – Researcher from the Wildlife Conservation Society and Masters student at the University of the South Pacific with research assistant Seru Saumakidonu during coral disease assessment surveys in Leleuvia

Right: Yashika Nand – Researcher from the Wildlife Conservation Society and Masters student at the University of the South Pacific with research assistant Seru Saumakidonu during coral disease assessment surveys in Leleuvia

Information gathered on coral health was assigned to four major categories as shown below:

Coral disease assessments have shown that Namena has the highest percentage of healthy corals. However, the percentage occurrence of corals with “white signs” is similar across the all locations. These results are unable to make predations on the distribution/prevalence of white type diseases because signs caused by predation, bleaching and diseases were all clumped under the same category.

Furthermore, Vatu-i-Ra reefs showed highest percentage of corals with other color/type signs.

These results can only provide information on distribution patterns of potential diseases based on general categories.

Corals that are healthy

Corals that are healthy

Corals with white signs

Corals with white signs

Corals that were partly dead

Corals that were partly dead

Corals with other color/type signs

Corals with other color/type signs

Despite being unable to predict a distribution pattern for coral diseases, preliminary results clearly indicate that reef systems within the Vatu-i-Ra seascape are in a “healthy state”. However, Vatu-i-Ra reefs showing high percentage of “corals with color/type signs” could be of concern. This category encompasses corals that have potential signs of black band disease (is a threat that can cause of a lot of damage to the reefs); growth anomalies and pigmentation response (have not yet been documented as a major threat).

Even distribution of corals with “white signs” along the seascape could be of major concern. Coral with “white signs”, include those caused by bleaching, predation (outbreak of crown-of-thorn starfish and Drupella snail, fish feeding marks), white syndrome and white spot diseases that are considered major threat to reef systems. The distribution patterns of coral diseases is unclear along the Vatu-i-Ra seascape, however, results from more extensive research conducted on reef systems in Leleuvia and Nanuya Lailai will be able to predict a general pattern of distribution and prevalence of coral diseases on Fiji’s reefs.