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This special issue ofDiversity and Distributionspresents six papers that contribute to the assembly of a general research agenda for studying long-distance dispersal (LDD) across a variety of taxonomic groups (e.g. birds, fish, aquatic invertebrates and plants), ecosystems (e.g. terrestrial and marine ecosystems, wetlands and grasslands) and thematic fields (e.g. biological transport, marine biology, biogeochemistry and biodiversity conservation). This editorial emphasizes the need to develop a network integrating different research approaches (‘yellow brick roads’) to address the great challenge (‘finding the end of the rainbow’) of quantifying, understanding and predicting LDD and its implications. I review the key avenues for future research suggested in the special issue contributions, and stress the critical importance of properly considering the spatial and temporal scales relevant to the process and system of interests. I propose combining absolute and proportional definitions of LDD as a default practice in any investigation of LDD processes. When LDD is defined primarily by an absolute critical distance that characterizes key feature(s) of the system of interest, a quantitative assessment of the proportion of dispersal events expected to move beyond this critical threshold distance should also be provided. When LDD is defined primarily by a certain small fraction of dispersal events that travel longer than all others, an estimate of the absolute distance associated with this high percentile at the tail of the dispersal curve should also be added. [ABSTRACT FROM AUTHOR]

Dispersal is universally considered important for biodiversity conservation. However, the significance of long- as opposed to short-distance dispersal is insufficiently recognized in the conservation context. Long-distance dispersal (LDD) events, although typically rare, are crucial to population spread and to maintenance of genetic connectivity. The main threats to global biodiversity involve excessive LDD of elements alien to ecosystems and insufficient dispersal of native species, for example, because of habitat fragmentation. In this paper, we attempt to bridge the gap in the treatment of LDD by reviewing the conservation issues for which LDD is most important. We then demonstrate how taking LDD into consideration can improve conservation management decisions. [ABSTRACT FROM AUTHOR]

The Guayana Highlands ( GH) are virtually pristine environments and constitute a unique natural laboratory to study the biogeographical and evolutionary origin of the Neotropical biota. In addition, the GH provide most of the water of the Guayana region, which feeds the more important tributaries of the Orinoco and the Amazon basins. However, the biota and the ecosystems of the GH are in danger of being profoundly altered by current human activities. Recent studies have identified the presence of aggressive invader plant species (e.g. Poa annua and Polypogon elongatus) and infectious faecal bacteria ( Helicobacter pilori), both carried by tourists, which could deeply affect biodiversity and ecological performance of terrestrial and aquatic GH ecosystems. If these hazards are not controlled as soon as possible, the potential consequences could disturb not only the GH ecosystems but also those of the rest of the Guayana region. We still have time to find solutions and implement specific regulations before the mentioned threats become uncontrollable. The GH are within a national park and other conservation figures but a management plan is lacking; therefore, current conservation rules are insufficient to deal with the newly detected menaces. We propose an international initiative, including all countries of the Guayana Shield, to take immediate actions. Otherwise, we are in danger of losing one of the few pristine biomes that remain in the world. [ABSTRACT FROM AUTHOR]

Aim Global conservation policies, such as the Convention on Biological Diversity ( CBD) decision to aim for the protection of 17% of the area of terrestrial ecosystems by 2020, are typically realized at national levels. We investigate the difference between continentally coordinated conservation versus nationally devolved conservation, in a manner relevant for the Nagoya resolution. Location The terrestrial areas of the Western Hemisphere. Methods We used IUCN distribution data for 8463 species of mammals, birds and amphibians in the Western Hemisphere. We investigated the consequences of prioritizing land at a continental scale, versus analysing priorities within each country separately. Spatial prioritization was performed using the Zonation software, which produces a complementarity-based hierarchical priority ranking across the area of interest. Results We found that coordinated continent-wide priorities achieved > 50% higher mean protection levels than national analyses for the top 17% of land. National prioritizations also result in spatial priority patterns that can be considered as artefacts at the continental scale: in bands of high-priority land concentrated at terrestrial political boundaries, such as at low-latitude edges of temperate zone countries. We find that this edge artefact also correlates with the present distribution of conservation areas, with the density of conservation areas within 50 km of a national border being > 50% higher than the density of conservation areas away from national borders. Main conclusions The means by which national priorities are integrated with continental or global conservation prioritization will have considerable influence on how much is achieved by the CBD resolution. Focus on national species distributions and priorities will result in lost performance because of emphasis on nationally rare species that are comparatively common elsewhere. National borders intersect species distributions (and possibly diversity gradients), leading to clustering of nationally rare species and priority areas close to the border. [ABSTRACT FROM AUTHOR]

South Africa's first national assessment of spatial priorities for biodiversity conservation, released in 2005, aimed to identify conservation priority areas for mainstreaming into all sectors at national and provincial scales. This National Spatial Biodiversity Assessment (NSBA) was based on a planning for implementation approach in order to deliver defensible products useful to decision-makers. The NSBA aimed to produce a map of broad-scale priority areas for future finer-scale assessment and conservation action. This map summarized information on species, ecosystems, ecological processes, and the pressures they face from human activities. Owing to the complexity of the priority area map, two additional user-friendly products — maps of ecosystem status and protection levels — were developed. These products represented the habitat loss and protected area coverage of South Africa's ecosystems relative to their conservation targets. A year after release, we reflect on the NSBA process, products and uptake by implementing agencies (with a specific focus on the terrestrial biodiversity assessment) in order to contribute to the growing body of documented best practice in conservation planning. The ecosystem status product has been widely used at national and provincial scales due in large to its clear and compelling message. The protection level and overall priority map have also witnessed uptake, the former in guiding the expansion of protected areas and the latter as an integrated map of national biodiversity status. The strong collaboration of local planners and implementers with in-depth experience of biodiversity assessment, using a systematic approach and focusing on communicating a few high level messages, appears to have contributed to the initial, successful uptake of the NSBA. We conclude with a call to address data and monitoring shortcomings before the next NSBA in 2010. [ABSTRACT FROM AUTHOR]