18 DEC 2014: New Study Maximizes Benefits of No-Take Marine Reserves for Coral Reef Fisheries

Arlington, Virginia — A new paper gives conservation practitioners unprecedented access to species-specific information to use in the design and monitoring of tropical no-take marine reserves. Scientists with The Nature Conservancy and several partner organizations (the Australian Research Council Centre of Excellence for Coral Reef Studies, the Coastal Conservation and Education Foundation, the Laboratoire d’Excellence ‘CORAIL’, The University of Hawaii at Hilo, Silliman University and the University of Queensland) reviewed and analyzed movement patterns of 34 families (210 species) of coral reef fishes.

“Synthesizing this information allows us, for the first time, to provide recommendations regarding the configuration (size, spacing and location) of no-take marine reserves (also known as fisheries closures or replenishment areas) to maximize their benefits for coral reef fisheries management and biodiversity protection,” said Alison Green, senior marine scientist in the Asia Pacific program at The Nature Conservancy.

Well-Designed Marine Reserves

How local populations of fish species are connected to one another is a key ecological factor to consider in marine reserve network design. For marine reserves to protect biodiversity and enhance fisheries outside their boundaries, they must be able to sustain focal species within their boundaries, and be spaced such that they are mutually replenishing and provide spillover of adults and larval to fished areas. As a result, the configuration (size, spacing and location) of individual reserves within a network should be informed by larval dispersal and movement patterns of the species for which protection is required. In the past, empirical data on larval dispersal and movement patterns of adults and juveniles of many tropical marine species have been unavailable or inaccessible to practitioners responsible for marine reserve design.

Photo: Trina Leberer

Results and Implications

This review of movement patterns of 34 families (210 species) of coral reef fishes demonstrates that movement patterns (home ranges, ontogenetic shifts and spawning migrations) vary among and within species, and are influenced by a range of factors (e.g., size, sex, behavior, density, habitat characteristics, season, tide and time of day).  Some species move <0.1–0.5 km (e.g. damselfishes, butterflyfishes and angelfishes), <0.5–3 km (e.g. most parrotfishes, goatfishes and surgeonfishes) or 3–10 km (e.g. large parrotfishes and wrasses), while others move tens to hundreds (e.g. some groupers, emperors, snappers and jacks) or thousands of kilometers (e.g. some sharks and tuna). Larval dispersal distances tend to be <5–15 km, and self-recruitment is common. The recommendations from this paper are:
·         Marine reserves should be more than twice the size of the home range of focal species (in all directions), thus marine reserves of various sizes will be required depending on which species require protection, how far they move and if other effective protection is in place outside reserves;
·         Reserve spacing should be < 15 km, with smaller reserves spaced more closely; and
·         Marine reserves should include habitats that are critical to the life history of focal species (e.g., home ranges, nursery grounds, migration corridors and spawning aggregations), and be located to accommodate movement patterns among these.

“We also provide practical advice for practitioners about how to use this information to design, evaluate and monitor the effectiveness of marine reserve networks within broader ecological, socioeconomic and management contexts,” added Rebecca Weeks, a postdoctoral research fellow at the Australian Research Center of Excellence for Coral Reef Studies.

This paper is the latest in a series of scientific reviews to provide ecological guidelines for improving the benefits of tropical marine protected areas for fisheries management and biodiversity in the face of climate change all of which are available at:  www.coraltriangleinitiative.org.

The paper is available online at:  http://onlinelibrary.wiley.com/doi/10.1111/brv.12155/abstract