|Chair(s)/Moderator(s): Bruno, John |
C12.1 15:00 How effective are Caribbean MPAs? Bruno, JB *, UNC Chapel Hill; Cox, CE UNC Chapel Hill; Valdivia, A UNC Chapel Hill; McField, M Healthy People Initiative; Fieseler, C UNC Chapel Hill; |
Abstract: As a universal remedy in coral reef management, in addition to protecting fishes, Marine Protected Areas (MPAs) are thought to restore coral populations by promoting herbivory and suppressing macroalgae. We asked whether MPAs affected these and other measures of âreef resilienceâ. We performed reef surveys from 1997 through 2013 at 16 sites along the Belize Barrier Reef, including 8 MPAs (3 of which were no-take reserves) and 8 unprotected control sites, quantifying fish and benthic communities. Although no-take reserves had a positive effect on the biomass of parrotfishes and predatory fishes, they have been ineffective in preventing coral to macroalgal phase shifts over the last 15 years. We speculate small MPA size, limited enforcement, and the predominance of disturbances not mitigated by local protection limit the effectiveness of this widely adopted management tool. Our results are concordant with other Caribbean case studies: MPAs (especially no-take reserves) can conserve fish populations (to varying degrees) yet do not appear to affect reef-building corals. Even complete and effective fisheries restriction fails to mitigate the impacts of storms, disease outbreaks, and ocean warming on coral reef benthic community structure. The marine conservation community should accept the limitations of MPAs, greatly expand and fund fully protected reserves, and develop and test new strategies to mitigate the many threats to coral reef ecosystems.
C12.2 15:15 Evaluating a New Strategy to Restore Parrotfish Populations in Belize . Cox, Courtney *, University of North Carolina at Chapel Hill; Bruno, John University of North Carolina at Chapel Hill; |
Abstract: Parrotfish populations have declined throughout the Caribbean due to overfishing. Functional loss of these key grazers has contributed to a shift in reef community structure from coral to algal dominance. In an effort to restore parrotfish populations and coral reef benthic community state, the Belize Fisheries Department implemented a national ban on parrotfish harvesting in 2009. Here, we assess the effectiveness of this fishing ban by (1) using genetic testing to reveal the proportion of parrotfish sold in local markets, (2) evaluating parrotfish population recovery and changes in benthic cover from 2009 to 2013 using underwater surveys, and (3) projecting the recovery response of parrotfish populations over time using a size-structured population model. We found that 7% of 104 fillets collected from fish markets across Belize were identified as illegal parrotfish and 51% were mislabeled (with large variation among cities in mislabeling). So far, parrotfish density has only increased for smaller size classes (6 cm to 20 cm), and macroalgal cover and coral recruitment have not yet been affected. Population forecast models predict that a minimum of 10 years is needed to reach a stable size distribution (i.e., population recovery). We conclude that the ban has been effective in some ways (fewer parrotfish sold in markets, more smaller individuals); however, more time is needed for this management approach to restore large parrotfish with the potential to reduce macroalgal cover.
C12.3 15:30 Setting conservation targets in marine ecosystems: a socio-ecological approach. Phillip Levin *, NOAA Fisheries; Amada Rehr NOAA Fisheries; Greg Williams NOAA Fisheries; Karma Norman NOAA Fisheries; Chris Harvey NOAA Fisheries; |
Abstract: âMaking marine science matterâ requires that we develop means to resolve conflicting uses of marine ecosystems that considers the diverse values that underpin such conflicts. In a practical sense, such conflicts are most apparent in setting conservation targets. Because targets are an expression of the desired state of the ecosystem, establishing targets must include ecological understanding and societal values. Here, we report on an approach for identifying scientifically rigorous ecosystem targets that explicitly considers social perspectives. Using a case study from the California Current, we will illustrate a method that first used Bayesian Belief Networks to link management actions to changes in coastal habitats. We then used a food web model to examine changes to ecosystem attributes that result from simulated changes in nearshore habitat and water quality. Finally, we conducted large-scale social norm analyses in which stakeholders were asked to rate the desirability of a range of potential ecosystem futures. By explicating linking trade-offs inherent in socio-ecological systems with societal values, we provide a transparent means for identifying management targets for EBM.
C12.4 15:45 Darwin Initiative to strengthen the Worldâs Largest Marine Protected Area, Chagos Archipelago. Turner,J.R *, Bangor University, Wales UK; Sheppard, C. University of Warwick, UK; Koldewey, H Zoological Society of London; |
Abstract: The British Indian Ocean Territory (BIOT) Chagos MPA covers 640,000 km2 of ocean and is one of the âBig Sixâ Network of Ocean Legacy Marine Reserves, which aim to significantly increase strict protection of multiple ocean ecosystems. The MPA represents 60% of the worldâs no-take area and is of sufficient size to protect both site-attached and migratory species including 50% of the regionâs most healthy coral reefs, the worldâs largest atoll, 60,000km2 of shallow water habitats, a rich pelagic regime, an abyssal trench and half of all seamounts in the Indian Ocean. Chagos is an internationally important refuge site harbouring 76 threatened species including Hawksbill turtle, Redfoot booby, silky shark, Coconut crab, and Bigeye tuna, and an important reference site because its coral reefs have proven to be more resilient to climate change due to the absence of direct human impact. Cessation of fishing has prevented the by-catch of over 10,000 sharks per year. Long-term benefits of the MPA will be the protection of biodiversity in a wide range of ecosystems, and protection of functional links between ecosystems, and of migratory species. However, There challenges in managing and enforcing very Large MPAs. The scale of the MPA suggests that benefits will be significant at an ocean scale, and communities in some of the poorest countries around the Indian Ocean may benefit from the preservation of a genetically-balanced stock of species which may overspill propagules, juveniles and adults to unprotected regions.
C12.5 16:00 Fishing impacts on benthic ecosystems: Evidence requirements for effective fisheries management in Marine Protected Areas (MPAs). Pardoe, H , Natural England; Velterop, R Natural England; Fisher, R Natural England; Duffy, M Natural England; Vaughan, D *Natural England; |
Abstract: As a statutory adviser to the Government, Natural England is responsible for providing evidence-based advice on the potential impacts of fishing activities on habitats and species â for which MPAs have been, or will potentially be, designated (~25% of inshore waters). There is a wealth of research on the impacts of the most damaging fishing activities on habitats/species considered to be most sensitive (e.g. reef, seagrass, MaĂ«rl). Natural England have been working with UK regulators (IFCAs and the MMO) to provide evidence based conservation advice and develop management measures for these high risk interactions in English inshore waters. The focus has now shifted to the lower risk interactions to ensure the MPA network is effectively managed by 2016. However, the limited evidence base on which to inform management needs for less sensitive habitats (e.g. sandbanks) or less damaging activities (e.g. potting) still poses significant challenge. Determining thresholds at which a fishing activity will result in an unacceptable level of modification remains an elusive task. In the absence of a sound evidence-base to inform such practically implementable advice, Natural England and the fisheries regulators face a challenging balancing act between adopting precautionary management principles and utilising adaptive (essentially experimental) management and monitoring approaches in an attempt to address the uncertainties over time.
C12.6 16:15 Updating nursey sensitivity maps for British waters. GonzĂĄlez-Irusta, J.M. *, Marine Scotland Science; Aires, C. Marine Scotland Science; Watret, R. Marine Scotland Science; Wright, P.J. Marine Scotland Science; |
Abstract: To effectively manage the increasing range in offshore human activities requires a highly resolved understanding of the distribution of species and habitats sensitive to such pressures. This is especially important in areas like the North Sea where important fisheries have to co-exist with other offshore activities (e.g. oil and gas industry). With this objective, Marine Scotland Science (MSS) is currently updating information on the spawning and nursery areas in British waters. Nursery areas of eleven commercial species were defined on the basis of densities of age 0 juveniles > 75% of the long-term maximum. This approach combines data from ICES and dedicated MSS surveys to create a set of presence-absence points of high juvenile density. Juvenile aggregations presence/absence was then modelled in species-specific distribution models using Random Forest, with eleven relevant environmental layers. Model evaluation indicated that the models gave accurate results for the eleven species analysed. Salinity and temperature were the most important variables for most species, although the results were highly variable between species. There was also good agreement between the predicted extents of nursery areas with previous work for most of the species studied. Future work will model juvenile abundance instead of probability of presence and will consider how the extent and resolution of the environmental layers used affect the model prediction, especially in inshore areas.
C12.7 16:30 Is fishing really worth more than biodiversity? A case study in the oceanic eastern tropical Pacific. Martin, SL *, Scripps Institution of Oceanography; Ballance, LT NOAA Fisheries; Groves, T University of California San Diego; |
Abstract: Degradation of marine ecosystems and loss of biodiversity through the overexploitation of resources, habitat destruction, pollution and anthropogenic climate change has been well documented. Many ecosystem services, until recently, were assumed to hold no economic value because they were not traditionally traded in markets. Society has made decisions to maximize economic value by choosing something that has monetary value (e.g. commercial fisheries) over something that has no monetary value (e.g. biodiversity). Ecosystem service valuation for the ocean has primarily focused on coastal systems, such as coral reefs, mangroves and estuaries, with much less emphasis on open ocean ecosystems. However, as management for open ocean ecosystems moves toward more holistic approaches, efforts to value their services will need to progress. Our research provides a case study in the valuation of open ocean ecosystem services, with a view toward evaluating tradeoffs between fishing and biodiversity conservation. We focus on the oceanic eastern tropical Pacific (ETP), an area of 21 million km2 includes waters of 12 nations and the oceanic commons. We document the major ecosystem services provided by the ETP, identify the major user groups of these services, and quantify some economic values of these services using existing data from commercial fisheries and biodiversity conservation efforts in the region. Our results will contribute to this challenging, but critical, movement toward ecosystem-based management for the open ocean.