Protected Areas and Effective Biodiversity Conservation Le Saout, Soizic; Hoffmann, Michael; Shi, Yichuan ...
Science (American Association for the Advancement of Science),
11/2013, Letnik:
342, Številka:
6160
Journal Article
Recenzirano
Although protected areas (PAs) cover 13% of Earth's land (1), substantial gaps remain in their coverage of global biodiversity (2). Thus, there has been emphasis on strategic expansion of the global ...PA network (3-5). However, because PAs are often understaffed, underfunded, and beleaguered in the face of external threats (6, 7), efforts to expand PA coverage should be complemented by appropriate management of existing PAs. Previous calls for enhancing PA management have focused on improving operational effectiveness of each PA e.g., staffing and budgets (6). Little guidance has been offered on how to improve collective effectiveness for meeting global biodiversity conservation goals (3). We provide guidance for strategically allocating management efforts among and within existing PAs to strengthen their collective contribution toward preventing global species extinctions.
Protected areas (PAs) are the most important conservation tool, yet assessing their effectiveness is remarkably challenging. We clarify the links between the many facets of PA effectiveness, from ...evaluating the means, to analysing the mechanisms, to directly measuring biodiversity outcomes.
The first global assessment of amphibians provides new context for the well-publicized phenomenon of amphibian declines. Amphibians are more threatened and are declining more rapidly than either ...birds or mammals. Although many declines are due to habitat loss and overutilization, other, unidentified processes threaten 48% of rapidly declining species and are driving species most quickly to extinction. Declines are nonrandom in terms of species' ecological preferences, geographic ranges, and taxonomic associations and are most prevalent among Neotropical montane, stream-associated species. The lack of conservation remedies for these poorly understood declines means that hundreds of amphibian species now face extinction.
Aim: Bird migration poses a challenge to macroecology, because with one in five species moving twice yearly between breeding and non-breeding grounds, macroecological patterns in birds are dynamic ...rather than static. But migration is also a natural experiment for testing hypotheses about the ecological mechanisms driving species distributions. Here, we use macroecological patterns of migratory bird diversity to test whether seasonality, winter harshness and the cost of migration drive the global distribution of migratory birds. Location: Global. Methods: We used data on the distribution of the world's bird species to derive global empirical patterns of: the number of breeding migrants, the number of non-breeding migrants and the difference in seasonal diversity. We built statistical models with ecologically meaningful predictors related to each of the hypotheses and investigated if they can significantly explain global empirical patterns of migratory bird diversity. We formally tested these models by training on one hemisphere (Western or Eastern) to predict the other hemisphere in turn. Model predictions were assessed in terms of match to the empirical data and their ability to predict the spatial features of patterns. Results: We found strong support for the hypotheses that birds move to breeding grounds to exploit a surplus in resources, preferring areas with harsh winters (presumably to avoid competition). In contrast, distribution during the nonbreeding season seems driven by avoidance of harsh winters and connectivity to breeding grounds. Models integrating these hypotheses explain well the observed variance in the empirical patterns and reproduce key spatial features, even when models trained in one hemisphere are used to predict another. Main conclusions: The strong predictive power of the models suggests that we have captured the main mechanisms that drive global patterns in bird migration. The fact that the models perform well despite being applied to species with very different ecologies suggests general mechanisms driving migration across taxa.
Abstract
Protected areas (PAs) are the cornerstones of global biodiversity conservation efforts, but to fulfil this role they must be effective at conserving the ecosystems and species that occur ...within their boundaries. Adequate monitoring datasets that allow comparing biodiversity between protected and unprotected sites are lacking in tropical regions. Here we use the largest citizen science biodiversity dataset – eBird – to quantify the extent to which protected areas in eight tropical forest biodiversity hotspots are effective at retaining bird diversity. We find generally positive effects of protection on the diversity of bird species that are forest-dependent, endemic to the hotspots, or threatened or Near Threatened, but not on overall bird species richness. Furthermore, we show that in most of the hotspots examined this benefit is driven by protected areas preventing both forest loss and degradation. Our results provide evidence that, on average, protected areas contribute measurably to conserving bird species in some of the world’s most diverse and threatened terrestrial ecosystems.
The Brazilian Amazon is globally important for biodiversity, climate, and geochemical cycles, but is also among the least developed regions in Brazil. Economic development is often pursued through ...forest conversion for cattle ranching and agriculture, mediated by logging. However, on the basis of an assessment of 286 municipalities in different stages of deforestation, we found a boom-and-bust pattern in levels of human development across the deforestation frontier. Relative standards of living, literacy, and life expectancy increase as deforestation begins but then decline as the frontier evolves, so that pre- and postfrontier levels of human development are similarly low. New financial incentives and policies are creating opportunities for a more sustained development trajectory that is not based on the depletion of nature and ecosystem services.
Humanity will soon define a new era for nature-one that seeks to transform decades of underwhelming responses to the global biodiversity crisis. Area-based conservation efforts, which include both ...protected areas and other effective area-based conservation measures, are likely to extend and diversify. However, persistent shortfalls in ecological representation and management effectiveness diminish the potential role of area-based conservation in stemming biodiversity loss. Here we show how the expansion of protected areas by national governments since 2010 has had limited success in increasing the coverage across different elements of biodiversity (ecoregions, 12,056 threatened species, 'Key Biodiversity Areas' and wilderness areas) and ecosystem services (productive fisheries, and carbon services on land and sea). To be more successful after 2020, area-based conservation must contribute more effectively to meeting global biodiversity goals-ranging from preventing extinctions to retaining the most-intact ecosystems-and must better collaborate with the many Indigenous peoples, community groups and private initiatives that are central to the successful conservation of biodiversity. The long-term success of area-based conservation requires parties to the Convention on Biological Diversity to secure adequate financing, plan for climate change and make biodiversity conservation a far stronger part of land, water and sea management policies.
Nearly one in five bird species has separate breeding and overwintering distributions, and the regular migrations of these species cause a substantial seasonal redistribution of avian diversity ...across the world. However, despite its ecological importance, bird migration has been largely ignored in studies of global avian biodiversity, with few studies having addressed it from a macroecological perspective. Here, we analyse a dataset on the global distribution of the world's birds in order to examine global spatial patterns in the diversity of migratory species, including: the seasonal variation in overall species diversity due to migration; the contribution of migratory birds to local bird diversity; and the distribution of narrow-range and threatened migratory birds. Our analyses reveal a striking asymmetry between the Northern and Southern hemispheres, evident in all of the patterns investigated. The highest migratory bird diversity was found in the Northern Hemisphere, with high inter-continental turnover in species composition between breeding and non-breeding seasons, and extensive regions (at high latitudes) where migratory birds constitute the majority of the local avifauna. Threatened migratory birds are concentrated mainly in Central and Southern Asia, whereas narrow-range migratory species are mainly found in Central America, the Himalayas and Patagonia. Overall, global patterns in the diversity of migratory birds indicate that bird migration is mainly a Northern Hemisphere phenomenon. The asymmetry between the Northern and Southern hemispheres could not have easily been predicted from the combined results of regional scale studies, highlighting the importance of a global perspective.
Biodiversity is not completely known anywhere, so conservation planning is always based on surrogates for which data are available and, hence, assumed effective for the conservation of unknown ...biodiversity. We review the literature on the effectiveness of surrogates for conservation planning based on complementary representation. We apply a standardized approach based on a Species Accumulation Index of surrogate effectiveness to compare results from 575 tests in 27 studies. Overall, we find positive, but relatively weak, surrogacy power. Cross-taxon surrogates are substantially more effective than surrogates based on environmental data. Within cross-taxon tests, surrogacy was higher for tests within the same realm (terrestrial, marine, freshwater). Surrogacy was higher when extrapolated (rather than field) data were used. Our results suggest that practical conservation planning based on data for well-known taxonomic groups can cautiously proceed under the assumption that it captures species in less well-known taxa, at least within the same realm.
Migration is a widespread response of birds to seasonally varying climates. As seasonality is particularly pronounced during interglacial periods, this raises the question of the significance of bird ...migration during past periods with different patterns of seasonality. Here, we apply a mechanistic model to climate reconstructions to simulate the past 50,000 years of bird migration worldwide, a period encompassing the transition between the last glacial period and the current interglacial. Our results indicate that bird migration was also a prevalent phenomenon during the last ice age, almost as much as today, suggesting that it has been continually important throughout the glacial cycles of recent Earth history. We find however regional variations, with increasing migratory activity in the Americas, which is not mirrored in the Old World. These results highlight the strong flexibility of the global bird migration system and offer a baseline in the context of on-going anthropogenic climate change.
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