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Riparian areas are biologically rich ecosystems, but they are highly threatened across the globe. Invertebrates represent a large proportion of the animal diversity within riparian areas, perform various ecological functions, and serve as bioenergetic links between aquatic and riparian food webs. Although many studies have been done on riparian taxa, this is the first synthesis of invertebrate ecology in riparian areas. We first discuss five characteristics of riparian zones that may support specialist riparian invertebrates: high rates of disturbance, elevated nutrient and water availability, increased vegetation and microhabitat diversity, strong microclimate gradients, and unique food resources. We then review how these mechanisms change with distance from the stream (lateral gradients) and position within a catchment (longitudinal gradients) and the resulting effects on the riparian community. Finally, we highlight gaps in our current knowledge and offer suggestions for future research. [ABSTRACT FROM AUTHOR]

The article offers information on the marine species condition at Upper Gulf of California. Topics discussed include concern for extinction of vaquita porpoise, most endangered marine mammal of Mexico; reduction of freshwater flow into the Upper Gulf of California (UGC) due to damming and diversion of the Colorado River, cause decline in vaquita; and collaborative efforts required among fishermen, the seafood supply chain, and environmental and fisheries agencies for conservative solution.

A great part of the Earth's biodiversity occurs on islands, to which humans have brought a legion of invasive species that have caused population declines and even extinctions. The domestic cat is one of the most damaging species introduced to islands, being a primary extinction driver for at least 33 insular endemic vertebrates. Here, we examine the role of feral cats in the context of the island biodiversity crisis, by combining data from reviews of trophic studies, species conservation status reports, and eradication campaigns. The integration of these reviews permits us to identify priority islands where feral cat eradications are likely to be feasible and where cats are predicted to cause the next vertebrate extinctions. Funding agencies and global conservation organizations can use these results to prioritize scarce conservation funds, and national and regional natural resource management agencies can rank their islands in need of feral cat eradication within a global context. [ABSTRACT FROM AUTHOR]

Biodiversity conservation in an era of global change and scarce funding benefits from approaches that simultaneously solve multiple problems. Here, we discuss conservation management of the island scrub-jay (Aphelocoma insularis), the only island-endemic passerine species in the continental United States, which is currently restricted to 250-square-kilometer Santa Cruz Island, California. Although the species is not listed as threatened by state or federal agencies, its viability is nonetheless threatened on multiple fronts. We discuss management actions that could reduce extinction risk, including vaccination, captive propagation, biosecurity measures, and establishing a second free-living population on a neighboring island. Establishing a second population on Santa Rosa Island may have the added benefit of accelerating the restoration and enhancing the resilience of that island's currently highly degraded ecosystem. The proactive management framework for island scrub-jays presented here illustrates how strategies for species protection, ecosystem restoration, and adaptation to and mitigation of climate change can converge into an integrated solution. [ABSTRACT FROM AUTHOR]

Site conservation is among the most effective means to reduce global biodiversity loss. Therefore, it is critical to identify those sites where unique biodiversity must be conserved immediately. To this end, the concept of key biodiversity areas (KBAs) has been developed, seeking to identify and, ultimately, ensure that networks of globally important sites are safeguarded. This methodology builds up from the identification of species conservation targets (through the IUCN Red List) and nests within larger-scale conservation approaches. Sites are selected using standardized, globally applicable, threshold-based criteria, driven by the distribution and population of species that require site-level conservation. The criteria address the two key issues for setting site conservation priorities: vulnerability and irreplaceability. We also propose quantitative thresholds for the identification of KBAs meeting each criterion, based on a review of existing approaches and ecological theory to date. However, these thresholds require extensive testing, especially in aquatic systems. INSETS: The Alliance for Zero Extinction;Key biodiversity areas in Madagascar;Overview of key biodiversity area criteria;Congruence between restricted-range birds, mammals, and... [ABSTRACT FROM AUTHOR]

Global conservation assessments require information on the distribution of biodiversity across the planet. Yet this information is often mapped at a very coarse spatial resolution relative to the scale of most land-use and management decisions. Furthermore, such mapping tends to focus selectively on better-known elements of biodiversity (e.g., vertebrates). We introduce a new approach to describing and mapping the global distribution of terrestrial biodiversity that way help to alleviate these problems. This approach focuses on estimating spatial pattern in emergent properties of biodiversity (richness and compositional turnover) rather than distributions of individual species, making it well suited to lesser-known, yet highly diverse, biological groups. We have developed a global biodiversity model linking these properties to mapped ecoregions and fine-scale environmental surfaces. The model is being calibrated progressively using extensive biological data sets for a wide variety of taxa. We also describe un analytical approach to applying our model in global conservation assessments, illustrated with a preliminary analysis of the representativeness of the world's protected-area system. Our approach is intended to complement, not compete with, assessments based on individual species of particular conservation concern. [ABSTRACT FROM AUTHOR]

Protected areas are the single most important conservation tool. The global protected-area network has grown substantially in recent decades now occupying 11.5% of Earth's land surface, hut such growth has not been strategically aimed at maximizing the coverage of global biodiversity. In a previous study, we demonstrated that the global network is far from complete, even for the representation of terrestrial vertebrate species. Here we present a first attempt to provide a global framework for the next step of strategically expanding the network to cover mammals, amphibians, freshwater turtles and tortoises, and globally threatened birds. We identify unprotected areas of the world that have remarkably high conservation value (irreplaceability) and are under serious threat. These areas concentrate overwhelmingly in tropical and subtropical moist forests, particularly on tropical mountains and islands. The expansion of the global protected-area network in these regions is urgently needed to prevent the loss of unique biodiversity. [ABSTRACT FROM AUTHOR]

Protected-area targets of 10% of a biome, of a country, or of the planet have often been used hi conservation planning. The new World Database on Protected Areas shows that terrestrial protected-area coverage now approaches 12% worldwide. Does this mean that the establishment of new protected areas can ceased This was the core question of the "Building Comprehensive Protected Area Systems" stream of the Fifth World Parks Congress in Durban, South Africa, in 2003. To answer it requires global gap analysis, the subject of the special section of BioScience for which this article serves as an introduction. We also provide an overview of the extraordinary data sets now available to allow global gap analysis and based on these, an assessment of the degree to which existing protected-area systems represent biodiversity. Coverage varies geographically, but is less than 2% for some bioregions, and more than 12% of 11,633 bird, mammal, amphibian, and turtle species are wholly unrepresented. The global protected-area systems are far from complete. [ABSTRACT FROM AUTHOR]

Discusses Mexico's Sian Ka'an Biosphere Reserve, which allows experimental scientific research as well as human habitation and use of natural resources. Observation that the reserve is one of an international network of protected areas launched by Unesco's Man and Biosphere Program (MAB) in the 1970s; Comparison of the designation of biosphere reserve to national parks; Conservation role of the biosphere preserve, which calls for the preservation of a minimally disturbed ecosystem large enough to ensure maintenance of both species and genetic diversity over time.

Within our lifetimes, at least a fifth of all plants and animals on earth are likely to become extinct. Federal officials have drafted a US government strategy to preserve biological diversity in the Third World. Called the `US Strategy on the Conservation of Biological Diversity' the report calls for several changes in the way The Agency for International Development reviews environmental impacts of projects they sponsor.

Presents a reader response to an article appearing in a previous issue of 'Bioscience' about the problems associated with the conservation of Hawaiin birds. Why the forest passernines are such a great loss to Hawaii; Inaccuracies with respect to Hawaii's efforts at forest-bird conservation and the acquired knowledge about those birds. INSET: J.M. Scott, C.B. Kepler, C. van Riper III, C. Stone, and S.I....