A new study led by John N. Kittinger, a graduate fellow in the Dept. of Geography at the University of Hawaii at Manoa, has found that not all coral reef degradation is irreversible. “Reefs can bounce back, if managed properly,” Kittinger says. However, the research also shows that reefs in the main Hawaiian Islands have been declining for the past 150 years.
Reconstructing 700 years of human-environment interactions in two different regions of the Hawaiian archipelago, the team of scientists identified key factors that have contributed to degradation or recovery of coral reefs. “Recoveries tell us that methods of traditional Hawaiian management were effective in historical times and the current problems we face are not new, unsolvable problems,” says Kittinger, who currently works at Stanford University’s Center for Ocean Solutions.
“We found reefs in the Northwest Hawaiian Islands are some of the best reefs anywhere in the world in terms of their ecological condition,” Kittinger reveals. “The main Islands, by contrast, rank near the bottom and are highly degraded.” Robert H. Richmond, president of the International Society for Reef Studies, adds that the top three causes of coral reef degradation worldwide include land-based sources of pollution, over-exploitation of marine resources and bleaching events tied to global climate change. “Coral reefs are resilient and the most effective approach to restoration is restoring those conditions that support natural recovery,” he states. “This includes restoring water and bottom quality.”
In Palau, coral reefs recovered from an extensive bleaching event in 1998 after watershed discharges were controlled and fish populations maintained. Palau’s Marine Protection Act of 1994 returned to more a traditional stewardship approach to resource sustainability where closures were implemented in key areas and for key species. Reversing Hawaiian coral reef decline will require protection of a broad range of habitat types over large areas, such as marine no-take reserves, in addition to policies for the diverse community of ocean-users to be held accountable as collaborative stewards, Kittinger says. “Part of the problem is a lack of trust between disparate groups. We need increased cooperation… particularly between ocean-users, scientists, and managers, working together, learning about solutions that are feasible and implementable.”