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Concerted political attention has focused on reducing deforestation (1-3), and this remains the cornerstone of most biodiversity conservation strategies (4-6). However, maintaining forest cover may not reduce anthropogenic forest disturbances, which are rarely considered in conservation programmes (6). These disturbances occur both within forests, including selective logging and wildfires (7,8), and at the landscape level, through edge, area and isolation effects (9). Until now, the combined effect of anthropogenic disturbance on the conservation value of remnant primary forests has remained unknown, making it impossible to assess the relative importance of forest disturbance and forest loss. Here we address these knowledge gaps using a large data set of plants, birds and dung beetles (1,538, 460 and 156 species, respectively) sampled in 36 catchments in the Brazilian state of Para. Catchments retaining more than 69-80% forest cover lost more conservation value from disturbance than from forest loss. For example, a 20% loss of primary forest, the maximum level of deforestation allowed on Amazonian properties under Brazil's Forest Code (5), resulted in a 39-54% loss of conservation value: 96-171% more than expected without considering disturbance effects. We extrapolated the disturbance-mediated loss of conservation value throughout Para, which covers 25% of the Brazilian Amazon. Although disturbed forests retained considerable conservation value compared with deforested areas, the toll of disturbance outside Para's strictly protected areas is equivalent to the loss of 92,000-139,000 [km.sup.2] of primary forest. Even this lowest estimate is greater than the area deforested across the entire Brazilian Amazon between 2006 and 2015 (ref. 10). Species distribution models showed that both landscape and within-forest disturbances contributed to biodiversity loss, with the greatest negative effects on species of high conservation and functional value. These results demonstrate an urgent need for policy interventions that go beyond the maintenance of forest cover to safeguard the hyper-diversity of tropical forest ecosystems., Protecting tropical forests is a fundamental pillar of many national and international strategies for conserving biodiversity (4-6). Although improved regulatory and incentive measures have reduced deforestation rates in some tropical [...]

The tropics contain the overwhelming majority of Earth's biodiversity: their terrestrial, freshwater and marine ecosystems hold more than three-quarters of all species, including almost all shallow-water corals and over 90% of terrestrial birds. However, tropical ecosystems are also subject to pervasive and interacting stressors, such as deforestation, overfishing and climate change, and they are set within a socio-economic context that includes growing pressure from an increasingly globalized world, larger and more affluent tropical populations, and weak governance and response capacities. Concerted local, national and international actions are urgently required to prevent a collapse of tropical biodiversity.The immense biodiversity of tropical ecosystems is threatened by multiple interacting local and global stressors that can only be addressed by the concerted efforts of grassroots organizations, researchers, national governments and the international community., Author(s): Jos Barlow [sup.1] , Filipe França [sup.1] [sup.2] , Toby A. Gardner [sup.3] , Christina C. Hicks [sup.1] , Gareth D. Lennox [sup.1] , Erika Berenguer [sup.1] [sup.4] , [...]

Human-driven land-use changes increasingly threaten biodiversity, particularly in tropical forests where both species diversity and human pressures on natural environments are high (1). The rapid conversion of tropical forests for agriculture, timber production and other uses has generated vast, human-dominated landscapes with potentially dire consequences for tropical biodiversity (2-5). Today, few truly undisturbed tropical forests exist, whereas those degraded by repeated logging and fires, as well as secondary and plantation forests, are rapidly expanding (6,7). Here we provide a global assessment of the impact of disturbance and land conversion on biodiversity in tropical forests using a meta-analysis of 138 studies. We analysed 2,220 pairwise comparisons of biodiversity values in primary forests (with little or no human disturbance) and disturbed forests. We found that biodiversity values were substantially lower in degraded forests, but that this varied considerably by geographic region, taxonomic group, ecological metric and disturbance type. Even after partly accounting for confounding colonization and succession effects due to the composition of surrounding habitats, isolation and time since disturbance, we find that most forms of forest degradation have an overwhelmingly detrimental effect on tropical biodiversity. Our results clearly indicate that when it comes to maintaining tropical biodiversity, there is no substitute for primary forests., As the extent of primary forests is shrinking throughout the tropics, a growing body of work has quantified the biodiversity values of degraded tropical forests. The ecological responses following forest [...]

To purchase or authenticate to the full-text of this article, please visit this link: http://dx.doi.org/10.1111/j.1523-1739.2007.00794.x Byline: TOBY A. GARDNER (*[dagger]), TIM CARO ([dagger][double dagger]s.), EMILY B. FITZHERBERT (*[dagger]), TASILA BANDA ([double dagger]), PUNIT LALBHAI ([double dagger]) Keywords: biodiversity conservation; human use; Katavi; national parks; protected areas Abstract: Abstract: Despite wide agreement that strictly protected areas (World Conservation Union categories I-III) are the best strategy for conserving biodiversity, they are limited in extent and exclude many species of key conservation importance. In contrast, multiple-use management areas (categories IV-VI), comprising >60% of the world's protected-area network, are often considered of little value to biodiversity conservation, particularly in Africa, where they typically contain few charismatic large mammals. We sampled small mammals, amphibians, birds, butterflies, and trees at 41 sites along a four-step gradient of increasing human activity and decreasing conservation protection, from a well-protected Tanzanian national park to nonintensive agricultural land. Although preliminary, our results indicate that species richness of these five taxa did not decline along this gradient, but different management areas, occupying areas of largely similar habitat, hosted distinct communities of each taxon. Differences in species composition in the absence of manifest differences in species richness highlight the importance of developing landscape-scale conservation strategies and the danger of using either a limited suite of indicator taxa or umbrella species as surrogates for biodiversity. Although strictly protected areas perform a unique and vital conservation service in East Africa by protecting large mammals, areas that allow varied resource extraction activities still possess vital and complementary conservation value. Abstract (Spanish): El Valor de Conservacion de Areas de Uso Multiple en Africa Oriental Resumen: No obstante el acuerdo generalizado de que las areas protegidas estrictamente (categorias I-III de la Union Mundial para la Conservacion) son la mejor estrategia para la conservacion de la biodiversidad, estan limitadas en extension y excluyen a muchas especies de importancia clave para la conservacion. En contraste, las areas de uso multiple (categorias IV-VI), que comprenden >60% de la red mundial de areas protegidas, a menudo son consideradas de poco valor para la conservacion, particularmente en Africa, donde tipicamente contienen pocos mamiferos mayores carismaticos. Muestreamos mamiferos pequenos, anfibios, aves, mariposas y arboles en 41 sitios a lo largo de un gradiente de cuatro niveles de incremento en la actividad humana y decremento de la proteccion para conservacion, desde un parque nacional bien protegido en Tanzania hasta tierras de agricultura no intensiva. Aunque preliminares, nuestros resultados indican que la riqueza de especies de estos cinco taxa no declino a lo largo del gradiente, pero las areas con manejo diferente y con habitats similares, presentaron comunidades distintas de cada taxon. Las diferencias en la composicion de especies en ausencia de diferencias manifiestas en la riqueza de especies destacan la importancia del desarrollo de estrategias de conservacion a nivel de paisaje y resaltan el peligro de utilizar un conjunto limitado de taxa indicadores o de especies sombrilla como sustitutos de la biodiversidad. Aunque las areas estrictamente protegidas desempenan un servicio de conservacion unico y vital en Africa Oriental al proteger a mamiferos mayores, las areas en que se permiten actividades diversas de extraccion de recursos tambien poseen un valor vital y complementario para la conservacion. Author Affiliation: (*)Center of Ecology, Evolution and Conservation, School of Environmental Sciences, University of East Anglia, Norwich, NR4 7TJ, United Kingdom ([dagger])Tanzania Wildlife Research Institute, P.O. Box 661, Arusha, Tanzania ([double dagger])Department of Wildlife, Fish and Conservation Biology, University of California, Davis, CA 95616, U.S.A. Article History: Paper submitted October 1, 2006; revised manuscript accepted May 1, 2007. Article note: (s.) Address correspondence to T. Caro, email tmcaro@ucdavis.edu

The decline of corals on tropical reefs is usually ascribed to a combination of natural and anthropogenic factors, but the relative importance of these causes remains unclear. In this paper, we attempt to quantify the contribution of hurricanes to Caribbean coral cover decline over the past two decades using meta-analyses. Our study included published and unpublished data from 286 coral reef sites monitored for variable lengths of time between 1980 and 2001. Of these, 177 sites had experienced hurricane impacts during their period of survey. Across the Caribbean, coral cover is reduced by ~17%, on average, in the year following a hurricane impact. The magnitude of this immediate loss increases with hurricane intensity and with the time elapsed since the last impact. In the following year, no further loss is discernible, but the decline in cover then resumes on impacted sites at a rate similar to the regional background rate of decline for nonimpacted sites. There is no evidence of recovery to a pre-storm state for at least eight years after impact. Overall, coral cover at sites impacted by a hurricane has declined at a significantly faster rate (6% per annum) than nonimpacted sites (2% per annum), due almost exclusively to higher rates of loss in the year after impact in the 1980s. While hurricanes, through their immediate impacts, appear to have contributed to changing coral cover on many Caribbean reefs in the 1980s, the similar decline in coral cover at impacted and nonimpacted sites in the 1990s suggests that other stressors are now relatively more important in driving the overall pattern of change in coral cover in this region. The overall lack of post-hurricane recovery points to a general impairment of the regeneration potential of Caribbean coral reefs. Key words: Caribbean coral reefs; conservation; coral decline; disturbance; hurricanes; largescale patterns; temporal trends.

THE ANALYSIS BY T. A. GARDNER ET AL. OF THE decade-scale trajectory of reef decline in the Caribbean ('Long-term region-wide declines in Caribbean corals,' Reports, 15 Aug., p. 958) is [...]

It is becoming increasingly acknowledged that coral reefs are globally threatened (1, 2). Recent assessments suggest that 11% of the historical extent of coral reefs is already lost, while a [...], We report a massive region-wide decline of corals across the entire Caribbean basin, with the average hard coral cover on reefs being reduced by 80%, from about 50% to 10% cover, in three decades, Our meta-analysis shows that patterns of change in coral cover are variable across time periods but largely consistent across subregions, suggesting that local causes have operated with some degree of synchrony on a region-wide scale. Although the rate of coral loss has slowed in the past decade compared to the 1980s, significant declines are persisting. The ability of Caribbean coral reefs to cope with future local and global environmental change may be irretrievably compromised.

Nature 478, 378-381 (2011); doi:10.1038/nature10425 We identified a conversion error in some of the biodiversity values used in our meta-analysis. The meta-analysis requires both mean and standard deviation values for each record, and several studies reported 95% confidence intervals instead of standard deviation., Author(s): Luke Gibson, Tien Ming Lee, Lian Pin Koh, Barry W. Brook, Toby A. Gardner, Jos Barlow, Carlos A. Peres, Corey J. A. Bradshaw, William F. Laurance, Thomas E. Lovejoy, [...]

Nature 478, 378-381 (2011); doi:10.1038/nature10425 We identified a conversion error in some of the biodiversity values used in our meta-analysis. The meta-analysis requires both mean and standard deviation values for [...]