Marine Protected Areas Attract Coral-Eating PredatorsNewsroom
While creating marine protected areas (MPAs) helps increase coral cover and protect key fish species, it also attracts predators that eat the corals, according to the findings of a new study.
“It’s kind of the equivalent of an oasis out in the desert,” says Cody Clements, marine ecologist at the Georgia Institute of Technology and the lead author of the study, published 6 February in PLoS One. “They’re all going to migrate into this area where there’s abundant food.”
The study showed that small MPAs in Fiji actually attract crown-of-thorns sea stars (Acanthaster planci), which eat corals and decimate coral reefs.
In Fiji, the government owns the nation’s marine resources, but community leaders can establish fishing rules that are generally respected by the local people, and hundreds of communities have created small MPAs to preserve fish stocks and protect coral reefs.
These protected areas are part of a long tradition of marine resource management on Fiji. Historically, after the death of a local leader communities imposed a fishing restriction, called a tabu, on part of a nearby reef for 100 nights. The community would end this period of mourning by reopening the reef and harvesting fish for the celebration of the deceased leader.
“We’re using that concept and modernising it to be able to address overfishing,” says Alifereti Tawake, the founding director of the Fiji Locally Managed Marine Area Network. “The modern version of tabu… is to lengthen the period from 100 nights to one year, to three years… and some in perpetuity.”
But protecting the environment does come at a cost to the communities. Closing an area to fishing reduces what the community members can harvest.
“They want to have their fish and invertebrate populations for the future,” says Stacy Jupiter, a coral reef ecologist with the Wildlife Conservation Society. “But they also want to eat them.”
This makes the infestation a critical concern. The small size of these MPAs makes them vulnerable to sea stars. But it also means that communities can develop realistic strategies to tackle the problem.
Tawake says communities are well equipped to deal with the sea stars and some of them are already removing the coral predators and either burning them or turning them into a natural fertiliser.
While increased coral cover seems to attract sea stars, other factors such as high levels of nutrients in the sea may also contribute to sea star outbreaks.
Communities throughout the south Pacific — and the resources they manage — can benefit from Fiji’s experience, says Clements. “Lessons that you learned in Fiji or elsewhere can often be applicable to other places. It provides a sense of community… we’re all in this together trying to manage marine resources.”
(Story and photo courtesy of SciDev.Net. This piece was produced by SciDev.Net’s Asia & Pacific desk.)