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Schutte V.G.W.,University of North Carolina at Chapel Hill | Schutte V.G.W.,University of Georgia | Selig E.R.,University of North Carolina at Chapel Hill | Selig E.R.,Center for Applied Biodiversity Science | Bruno J.F.,University of North Carolina at Chapel Hill
Marine Ecology Progress Series | Year: 2010

Coral cover has declined on reefs worldwide with particularly acute losses in the Caribbean. Despite our awareness of the broad-scale patterns and timing of Caribbean coral loss, there is little published information on: (1) finer-scale, subregional patterns over the last 35 yr, (2) regional-scale trends since 2001, and (3) macroalgal cover changes. We analyzed the spatiotemporal trends of benthic coral reef communities in the Caribbean using quantitative data from 3777 coral cover surveys of 1962 reefs from 1971 to 2006 and 2247 macroalgal cover surveys of 875 reefs from 1977 to 2006. A subset of 376 reefs was surveyed more than once (monitored). The largest 1 yr decline in coral cover occurred from 1980 to 1981, corresponding with the beginning of the Caribbean-wide Acropora spp. white band disease outbreak. Our results suggest that, regionally, coral cover has been relatively stable since this event (i.e. from 1982 to 2006). The largest increase in macroalgal cover was in 1986, 3 yr after the regional die-off of the urchin grazer Diadema antillarum began. Subsequently, macroalgal cover declined in 1987 and has been stable since then. Regional mean (±1 SE) macroalgal cover from 2001 to 2005 was 15.3 ± 0.4% (n = 1821 surveys). Caribbeanwide mean (±1 SE) coral cover was 16.0 ± 0.4% (n = 1547) for this same time period. Both macroalgal and coral cover varied significantly among subregions from 2001 to 2005, with the lowest coral cover in the Florida Keys and the highest coral cover in the Gulf of Mexico. Spatio-temporal patterns from the subset of monitored reefs are concordant with the conclusions drawn from the entire database. Our results suggest that coral and macroalgal cover on Caribbean reef benthic communities has changed relatively little since the mid-1980s. © Inter-Research 2010, www.int-res.com. Source

Selig E.R.,University of North Carolina at Chapel Hill | Selig E.R.,Center for Applied Biodiversity Science | Bruno J.F.,University of North Carolina at Chapel Hill
PLoS ONE | Year: 2010

Background: A variety of human activities have led to the recent global decline of reef-building corals [1,2]. The ecological, social, and economic value of coral reefs has made them an international conservation priority [2,3]. The success of Marine Protected Areas (MPAs) in restoring fish populations [4] has led to optimism that they could also benefit corals by indirectly reducing threats like overfishing, which cause coral degradation and mortality [2,5]. However, the general efficacy of MPAs in increasing coral reef resilience has never been tested. Methodology/Principal Findings: We compiled a global database of 8534 live coral cover surveys from 1969-2006 to compare annual changes in coral cover inside 310 MPAs to unprotected areas. We found that on average, coral cover within MPAs remained constant, while coral cover on unprotected reefs declined. Although the short-term differences between unprotected and protected reefs are modest, they could be significant over the long-term if the effects are temporally consistent. Our results also suggest that older MPAs were generally more effective in preventing coral loss. Initially, coral cover continued to decrease after MPA establishment. Several years later, however, rates of coral cover decline slowed and then stabilized so that further losses stopped. Conclusions/Significance: These findings suggest that MPAs can be a useful tool not only for fisheries management, but also for maintaining coral cover. Furthermore, the benefits of MPAs appear to increase with the number of years since MPA establishment. Given the time needed to maximize MPA benefits, there should be increased emphasis on implementing new MPAs and strengthening the enforcement of existing MPAs. © 2010 Selig, Bruno. Source

Karyn T.,Center for Applied Biodiversity Science | Williams J.W.,University of Wisconsin - Madison
Ecological Applications | Year: 2010

Assessing the potential impacts of 21st-century climate change on species distributions and ecological processes requires climate scenarios with sufficient spatial resolution to represent the varying effects of climate change across heterogeneous physical, biological, and cultural landscapes. Unfortunately, the native resolutions of global climate models (usually approximately 2° X 2° or coarser) are inadequate for modeling future changes in, e.g., biodiversity, species distributions, crop yields, and water resources. Also, 21st-century climate projections must be debiased prior to use, i.e., corrected for systematic offsets between modeled representations and observations of present climates. We have downscaled future temperature and precipitation projections from the World Climate Research Programme's (WCRP's) CMIP3 multi-model data set to 10-minute resolution and debiased these simulations using the change-factor approach and observational data from the Climatic Research Unit (CRU). These downscaled data sets are available online and include monthly mean temperatures and precipitation for 2041-2060 and 2081-2100, for 24 climate models and the AlB, A2, and B1 emission scenarios. This paper describes the downscaling method and compares the downscaled and native-resolution simulations. Sharp differences between the original and downscaled data sets are apparent at regional to continental scales, particularly for temperature in mountainous areas and in areas with substantial differences between observed and simulated 20th-century climatologies. Although these data sets in principle could be downscaled further, a key practical limitation is the density of observational networks, particularly for precipitation-related variables in tropical mountainous regions. These downscaled data sets can be used for a variety of climate-impact assessments, including assessments of 21st-century climate-change impacts on biodiversity and species distributions. ©2010 by the Ecological Society of America. Source

Burn M.J.,University of Edinburgh | Burn M.J.,University of the West Indies | Mayle F.E.,University of Edinburgh | Killeen T.J.,Center for Applied Biodiversity Science | Killeen T.J.,Private University of Santa Cruz de la Sierra
Palaeogeography, Palaeoclimatology, Palaeoecology | Year: 2010

An ongoing controversy in Amazonian palaeoecology is the manner in which Amazonian rainforest communities have responded to environmental change over the last glacial-interglacial cycle. Much of this controversy results from an inability to identify the floristic heterogeneity exhibited by rainforest communities within fossil pollen records. We apply multivariate (Principal Components Analysis) and classification (Unweighted Pair Group with Arithmetic Mean Agglomerative Classification) techniques to floral-biometric, modern pollen trap and lake sediment pollen data situated within different rainforest communities in the tropical lowlands of Amazonian Bolivia. Modern pollen rain analyses from artificial pollen traps show that evergreen terra firme (well-drained), evergreen terra firme liana, evergreen seasonally inundated, and evergreen riparian rainforests may be readily differentiated, floristically and palynologically. Analogue matching techniques, based on Euclidean distance measures, are employed to compare these pollen signatures with surface sediment pollen assemblages from five lakes: Laguna Bella Vista, Laguna Chaplin, and Laguna Huachi situated within the Madeira-Tapajós moist forest ecoregion, and Laguna Isirere and Laguna Loma Suarez, which are situated within forest patches in the Beni savanna ecoregion. The same numerical techniques are used to compare rainforest pollen trap signatures with the fossil pollen record of Laguna Chaplin.Pollen assemblages of pollen traps situated within riparian forest communities are most similar to surface sediment samples from Lagunas Bella Vista and Chaplin. Pollen derived from terra firme forests also comprises a significant proportion of these assemblages. Together, these pollen spectra successfully identify riparian and terra firme rainforest communities surrounding the two lakes today. Close similarity between terra firme liana pollen trap assemblages and surface samples obtained from Laguna Huachi, a lake surrounded by relatively undisturbed liana forest, suggests liana forest pollen rain may also be identified within lake sediment records. Pollen spectra obtained from surface sediment samples from lakes situated within gallery forests of the Beni savanna ecoregion are significantly different to those obtained from the Madeira-Tapajós ecoregion, reflecting their different floristic compositions. By applying our findings to the previously published Laguna Chaplin Quaternary pollen record, we show that differentiation between riparian and terra firme rainforest pollen assemblages can lead to more robust and detailed palaeovegetation reconstructions than has hitherto been possible. © 2010 Elsevier B.V. Source

Treves A.,University of Wisconsin - Madison | Jones S.M.,University of Wisconsin - Madison | Jones S.M.,Center for Applied Biodiversity Science
Frontiers in Ecology and the Environment | Year: 2010

Labels on products are meant to influence consumer behavior. Consumers buying products labeled as ecofriendly may hope to help conserve the environment, but eco-labels vary in their claims and credibility. We define three types of wildlife-friendly eco-labels, according to their potential to conserve wildlife, and describe barriers to convincing consumers of their claims. Eco-labels we term "Supportive" donate revenues to conservation organizations and are, at best, indirect interventions, opaque to consumer scrutiny. "Persuasive" eco-labels certify manufacturing/collection practices, under the assumption that wildlife will benefit as a result. "Protective" eco-labels certify wildlife conservation, which can gain the highest level of credibility, but require the greatest verification effort. Proving that producers conserved wildlife is costly, time-consuming, and technically challenging, because wild animals ignore property boundaries and experience mortality and dispersal irrespective of people, but their population dynamics often obscure the role of human activities and economic practices. Nevertheless, wild animals are among the most inspiring and marketable components of the environment. © The Ecological Society of America. Source

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