Marine Reserve Swarming With Sharks
July 16, 2013
In Fiji's largest marine reserve, where fishing is banned, sharks are thriving. Marine researchers from WCS and the University of Western Australia have found that Namena Reserve—located on the southern coast of Fiji’s Vanua Levu Island—has two to four times more sharks compared to adjacent areas where fishing is permitted.
In a study published in the journal Coral Reefs, authors Jordan Goetze of WCS and the University of Western Australia and Laura Fullwood of the University of Western Australia say that the significantly higher availability of prey fish within Namena’s boundaries accounts for its shark densities. The 60-square-kilometer reserve was established in 1997 and is managed by local communities.
The researchers conducted their study during a three-week period in 2009. In order to survey the sharks, Goetze and the WCS Fiji team used stereo baited remote underwater video systems to record data at eight sites within the reserve and eight outside the reserve. The 60-minute video segments taken captured images of five different species of reef shark, providing the researchers with data on shark abundance.
Outside the reserve, in areas where fishing is permitted, the researchers found fewer sharks. They note that, because local Fiji communities traditionally considered sharks to be sacred, eating them is typically taboo. But as demand for shark products grows, higher prices are driving some locals to catch sharks. The island country’s shark populations are also vulnerable to foreign fishing fleets. Worldwide, increasing rates of harvesting are leading to the depletion of many shark species.
“The news from Fiji gives us solid proof that marine reserves can have positive effects on reef shark populations,” said Dr. Caleb McClennen, Director of WCS’s Marine Program. “Shark populations are declining worldwide due to the demand for shark products, particularly fins for the Asian markets. We need to establish management strategies that will protect these ancient predators and the ecosystems they inhabit.”
The study was made possible by the generous support of the David and Lucile Packard Foundation, the Gordon and Betty Moore Foundation, the Stavros Niarchos Foundation, and the University of Western Australia (UWA) Marine Science Honours program.