Geographical range is considered a good predictor of the levels of isozyme variation in plants. Widespread species, often consisting of historically larger and more continuous populations, maintain higher polymorphism and are less affected by drift, which tends to erode genetic variation in more geographically restricted species. However, widespread species occurring in small and disjunct populations may not fit this pattern. In this study we examined genetic variation in Pilgerodendron uviferum, a conifer endemic to temperate forests of southern South America.
Resource Type: Journal PapersAdvice on assessment of biodiversity impacts is required to support trade negotiations and reduce risks of unforeseen consequences for important biodiversity and those who depend on it for their livelihoods. This paper explores linkages between biodiversity and trade and draws on examples from the agriculture sector to reinforce the need to build a biodiversity-inclusive process for as-sessing impacts of trade policies and agreements.
Resource Type: Journal PapersGrowing deterministic and stochastic threats to many wild populations of large vertebrates have focused attention on the conservation significance of captive breeding and subsequent reintroduction. However, work on both gorillas and black rhinos questions this shift in emphasis. In these species, field-based conservation can be effective if properly supported and, although this is not cheap, per capita costs may still be considerably lower than for ex situ propagation in captivity. Here we attempt to broaden the scope of this debate by contrasting the breeding success and costs of in situ and captive programmes for a range of threatened mammals.
Resource Type: Journal PapersMost multilateral environmental agreements require Parties to report at regular intervals on the measures they have taken to implement the agreement. National reporting not only aims to inform the Convention bodies such as the secretariat or the Conference of the Parties of an improved implementation of the convention in question but also serves a number of other purposes.
Resource Type: Journal PapersThere is an urgent need to evaluate the status of groups of species for conservation purposes. A species' status is indicated by both its distribution and abundance, and the rate at which these components are changing. This information is scarce for many tropical forest species. We produced four measures of status based on locality and habitat data for 25 partridges and pheasants of Southeast Asia.
Resource Type: Journal PapersStipitate hydnoid ('tooth') fungi are considered to be threatened throughout much of central and northern Europe. In response to concern about the status of these fungi in the UK, a Biodiversity Action Plan has been developed for 14 species in this group. As a first step towards implementation of this plan, a number of surveys have been initiated, to determine the current status and distribution of hydnoid fungi. An overview of the results of these surveys is described. A series of distribution maps are presented, based on a compilation of early records and the results of a recent field survey in Scottish coniferous forests. The difficulties of interpreting early records are discussed, with particular reference to the taxonomie confusion that has surrounded this group of fungi. Although available data provide little evidence for decline of hydnoid fungi, a number of species display very restricted distributions within Scotland. The recent discovery of several species new to Britain emphasises the need for further field surveys to define the current status of these fungi with greater accuracy.
Resource Type: Journal PapersRecent CITES decisions that accepted an obligation to take into account the impacts of CITES listings on the livelihoods of the poor, have some affinities with the ‘Do no harm’ approach to the livelihoods of the poor. The process will produce guidelines and rapid assessment tools. If these guidelines and tools are to be effective they will need to take account of the context-specific nature of solutions in this area. The CITES case provides lessons for other international conservation institutions whose activities affect the livelihoods of the poor at the local level.
Resource Type: Journal PapersRuff breeding populations have declined widely and in all habitats across temperate Eurasia. Of an estimated population of 2.2-2.8 million birds, 98% are now confined to habitats in the Arctic tundra.
The emerging picture is that the population has shifted northwards and eastwards and has retreated from the wet grassland habitats formerly occupied along the southern edges of its range. It is suggested that the causes are probably of a global nature and may be linked with climate change. It is unclear whether the total population has declined or only shifted north and east. More co-ordinated and systematic monitoring of breeding and wintering populations will be necessary before a full understanding of these changes can be reached.
Resource Type: Journal PapersIn the past few years, a number of analyses have been undertaken to measure progress towards the 2010 and 2012 CBD targets. This report demonstrates how the measurement of progress is influenced by decisions on which protected areas are included (for instance, whether internationally designated sites, or sites without an assigned IUCN category are included) and which biogeographic datasets used (for instance which mountain dataset is chosen), and highlights the need for standardised methods and datasets.
Resource Type: Journal PapersThe effects of Pleistocene glaciations on the genetic characteristics of the most austral conifer in the world, Pilgerodendron uviferum, were analysed with specific reference to the hypothesis that the species persisted locally in ice-free areas in temperate South America.
Results indicated that Pilgerodendron populations are highly monomorphic, probably reflecting past population bottlenecks and reduced gene flow. Southernmost populations tend to be the least genetically variable and were therefore probably more affected by glacial activity than northern ones. Populations located outside ice limits seem to have been isolated during the glacial period. The presence of centres of genetic diversity, together with the lack of a significant correlation between genetic and geographical distances and the absence of geographical patterns of allelic frequencies at most analysed alleles, may indicate that Pilgerodendron did not advance southward after the last glaciation from a unique northern refugium, but spread from several surviving populations in ice-free areas in Patagonia instead.
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