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The Resilience of Fish SpeciesScientists Are Encouraged by the Effectiveness of No-Take Zones
A recent study on the Great Barrier Reef shows that overfished populations can recover in a short time when protected by no-take zones.
There are two sides to conservation—habitat and species. Without appropriate habitat, species cannot survive outside of zoos and aquaria. Without species, habitats will crash as a result of too little biomass. Conserving habitat and species needs to occur hand-in-hand, and, increasingly, habitat restoration (or even re-creation) must be a part of the equation. While this work is important, the resilience of species, when given appropriate protection, should also not be underestimated. Resilience Based on Sufficient Wild ProtectionThere is no doubt that zoos and aquaria play a critical role as a sort of modern day Noah’s ark—providing refuge for species until such time as habitat can be conserved, restored or rebuilt. Likewise, captive breeding programs play an essential role in maintaining a species’ genetic diversity sufficient to sustain the survival of that species. Amidst all of these captive programs, however, the study of a species’ resilience based solely on sufficient protection is sometimes forgotten. Scientists on Australia’s Great Barrier Reef were astounded recently, when they observed a remarkable recovery of the coral trout, which had rebounded by up to 75 percent on a majority of reefs included in a recently created (2004) network of no-take zones. The team of scientists, led by Professor Garry Russ of the ARC Centre of Excellence for Coral Reef Studies and Dr Hugh Sweatman of the Australian Institute of Marine Science (AIMS), published their results in the most recent issue of Current Biology (Current Biology, Volume 18, Issue 12, 24 June 2008, Pages R514-R515). Scientists Are Surprised at Coral Trout Population Recovery“We were very agreeably surprised at the speed at which coral trout populations recovered – and also the sheer scale and consistency of the response,” Russ says. Closing reefs to fishing is a controversial topic, as it has recreational, social and economic implications. Nonetheless, with so much of the data pointing toward an impending collapse of fisheries worldwide by as early as the middle of this century, establishing no-take zones has become a popular management strategy. And this study suggests that it seems to be working. “The results are very convincing, because we surveyed such a huge area–56 reefs spread over more than 1000 kilometers from north of Cairns to the Capricorn-Bunker islands in the south,” Dr Peter Doherty, Research Director of AIMS, says. “The data from these reefs was remarkably consistent – and we were pleasantly surprised to observe such rapid improvements in fish densities…. [I]t certainly looks as if the no-take marine reserves are working as hoped.” No-Take Zones Good for Fishing TooSome critics have claimed that creating no-take zones simply pushes the fishing pressure elsewhere, but advocates of no-take zones believe that protected reefs, where fishing is forbidden, will actually lead to better fishing on adjacent reefs that are open to fishing. Adult fishes living in protected zones can grow and reproduce in the protected zone, and the juveniles from no-take zones then migrate and settle in areas open to fishing.
The copyright of the article The Resilience of Fish Species in Environmentalism is owned by Ret Talbot. Permission to republish The Resilience of Fish Species in print or online must be granted by the author in writing.
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