A protected coral reef in Fiji briefly opened for an intensive five-week fishing season was largely depleted of its fish populations and has been slow to recover, according to a study by the Wildlife Conservation Society.
In the first study of its kind, conservationists with WCS’s Marine Program examined the environmental impact of an intensive fishing event—conducted by three villages in 2008 to pay for both school and church fees and provincial levies—on a formerly protected reef system.
The study appears in the recent online version of the journal Coral Reefs. The authors include: Stacy Jupiter, D.P. Egli, and A. Cakacaka of the Wildlife Conservation Society; R. Weeks of James Cook University and WCS; and A.P. Jenkins of Wetlands International.
Predictably, the research team found that the reef’s populations of large-bodied, commercially valuable species (surgeonfish, parrotfish, snapper, grouper, etc.) were severely depleted during the harvest, which lasted for five weeks, and some species were fished out entirely (the target of 12,000 Fiji dollars was achieved in the first day, but the fishing continued). Other species, the team speculated, may have simply fled to an adjacent reef outside of the fishing area.
After returning a year later, the marine scientists recorded a significantly lower fish biomass (a tally of all species based on visual surveys) in the reef than the previous year before the harvest. The findings also suggested that fishers may have continued to fish even after the fishing ban was reinstated.
The idea for the study was prompted by an announcement from the residents of the three villages on Kia Island. Seeking to raise funds to pay for needed services and taxes, the villagers temporarily opened a coastal no-take zone with a goal of generating 12,000 Fiji dollars (approximately $7,500) in fish and sea cucumbers. WCS researchers had surveyed the reef sites just prior to the announced harvests.
“We realized this would be a once-in-a-lifetime opportunity to directly assess the impacts of a huge harvest event in a coral reef normally closed to fishing,” said Dr. Stacy Jupiter, lead author of the study. “Many studies have examined the vulnerability of reef systems to overfishing. In this instance, we had a baseline in what was a protected area, followed by a survey of the site one month into the harvest and then a year later to gather evidence of recovery.”
The authors state that the fund-raising harvest and the subsequent impact of the fishing on the reef’s biomass provide a valuable warning on the threat of unsustainable fishing in Oceania, where overextraction for commercial sale is becoming more frequent. They recommend that future harvests must be controlled with a combination of restrictions on effort, gear, the duration of opening, access, and total catch. Further, the catch should be monitored to ensure that enough breeding adult fish remain to replenish local populations.
Community-based agreement, the authors say, is another critical component. Specifically, written and verbal concensus that details the process of how fishing events are authorized, carried out, and when and how they end.
“Coral reef systems are important resources for local communities in terms of both short-term economic needs and long-term food security,” said Dr. Caleb McClennen, director of WCS’s Marine Conservation. “Studies such as this are critical in finding the threshold beyond which use of marine resources becomes unsustainable.”
WCS’s work in Fiji has been made possible through the generous support of the John D. and Catherine T. MacArthur Foundation, The David and Lucile Packard Foundation, the Tiffany & Co. Foundation, and the National Oceanic and Atmospheric Administration.