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  Effects of population disjunction on isozyme variation in the widespread Pilgerodendron uviferum »

  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 Papers
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  Genetic variation in wild Chilean and cultivated British populations of Podocarpus salignus D. Don (Podocarpaceae) »

  The threatened Chilean conifer Podocarpus salignus D. Don is currently the focus of ex situ conservation eorts being undertaken by the Conifer Conservation Programme of the Royal Botanic Garden Edinburgh. To assess variation within in and ex situ populations of the species, leaf material collected from four wild populations was analysed by random amplified polymorphic DNA (RAPD).

  RAPD was found to be an effective tool for assessing the genetic structure of P. salignus, for providing a guide to future germplasm-sampling strategies, and for hybrid identification. Implications for genetic conservation of the species and the role of ex situ approaches are discussed.

  Resource Type: Journal Papers
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  Reconstructing the movements of free-ranging demersal Fish in the North Sea: a data-matching and simulation method »

  Demersal fish cannot be readily tracked using data loggers that provide satellite-based or light-based geolocation. Moreover, fish that are highly mobile within the water column cannot readily be located with other methods, such as the tidal location method (TLM). As an alternative, we describe a process that provides estimates of geographic location by simulating movement paths through geographic locations that match temperature and depth data recorded by data loggers.

  Resource Type: Journal Papers
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  Mapping community change in modified landscapes »

  We generated biodiversity surfaces for both present-day and pre-human landscapes to map spatial patterns of change in a diverse ecological community to calculate the combined biodiversity impacts of habitat loss and fragmentation that accounts for the exact spatial pattern of deforestation. Our spatially-explicit, landscape-scale index of community change shows how the fine-scale configuration of habitat loss sums across a landscape to determine changes in biodiversity at a larger spatial scale. After accounting for naturally occurring within-forest heterogeneity, we estimate that the conversion of 43% of forest to grassland in a 1300 km2 landscape in New Zealand resulted in a 47% change to the beetle community.

  Resource Type: Journal Papers
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  Outcomes, not implementation, predict conservation success »

  We applied a conceptual framework and score-card developed by the Cambridge Conservation Forum (CCF) to a sample of 60 conservation activities to determine the predictive power of implementation measures versus measures of key outcomes (later steps in the models defined in the CCF tools). We show that assessing key outcomes is often more difficult than quantifying the degree of implementation of a project but that, while implementation is a poor predictor of success, key outcomes provide a feasible and much more reliable proxy for whether a project will deliver real conservation benefits. The CCF framework and evaluation tool provide a powerful basis for synthesizing past experience and, with wider application, will help to identify factors that affect the success of conservation activities.

  Resource Type: Journal Papers
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  Extinction risk from climate change »

  Climate change over the past ~30 years has produced numerous shifts in the distributions and abundances of species1,2 and has been implicated in one species-level extinction3. Using projections of species' distributions for future climate scenarios, we assess extinction risks for sample regions that cover some 20 of the Earth's terrestrial surface. Exploring three approaches in which the estimated probability of extinction shows a powerlaw relationship with geographical range size, we predict, on the basis of mid-range climate-warming scenarios for 2050, that 15-37% of species in our sample of regions and taxa will be 'committed to extinction'. When the average of the three methods and two dispersal scenarios is taken, minimal climate-warming scenarios produce lower projections of species committed to extinction (~18) than mid-range (~24) and maximumchange (~35) scenarios. These estimates show the importance of rapid implementation of technologies to decrease greenhouse gas emissions and strategies for carbon sequestration.

  Resource Type: Journal Papers
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  A global overview of the conservation status of tropical dry forests »

  Virtually all of the tropical dry forests that remain are currently exposed to a variety of different threats, largely resulting from human activity. Taking their high biodiversity value into consideration, this indicates that tropical dry forests should be accorded high conservation priority. The results presented here could be used to identify which forest areas should be accorded highest priority for conservation action. In particular, the expansion of the global protected area network, particularly in Mesoamerica, should be given urgent consideration.

  Resource Type: Journal Papers
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  Distribution and stand characteristics of relict populations Mexican beech (Fagus grandifolia var. mexicana) »

  Fagus grandifolia var. mexicana (Mexican beech) is limited to about 10 populations (2-35 ha) in the Sierra Madre Oriental, Mexico. The objectives were to assess the current status and distribution of beech by surveying five sites. Species richness varied between three to 27 tree species in the canopy, and from nine to 29 species in the understorey. Basal area of trees greater than or equal to 5 cm dbh varied between 27.87 and 70.98 m2 ha-1, and density from 370 to 1290 individual ha-1. Beech represented 22-99.6 of total basal area, and 6.8-83.3 of total density. Beech dominance varied from monodominant to codominance with Carpinus caroliniana, Quercus spp., Liquidambar styraciflua, Magnolia schiedeana, and Podocarpus spp. Beech total population size ranged from 180 to 6300 trees with a total of less than 1300 individuals in four sites. Anthropogenic disturbance remains a major threat to these forests. It is uncertain whether Mexican beech will be able to survive without conservation efforts.

  Resource Type: Journal Papers
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  Biodiversity trends in Europe: development and testing of a species trend indicator for evaluating progress towards the 2010 target »

  This paper presents a trial of a species population trend indicator for evaluating progress towards the 2010 biodiversity target in Europe, using existing data. The indicator integrates trends on different species (groups), and can be aggregated across habitats and countries. Thus, the indicator can deliver both headline messages for high-level decision-making and detailed information for in-depth analysis, using data from different sources, collected with different methods.

  Resource Type: Journal Papers
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  Distribution, status, and proposals for the conservation of mountain gazelle Gazella gazella cora in south-west Saudi Arabia »

  Nineteen different areas in south-west Saudi Arabia from which mountain gazelle Gazella gazella cora were reported between 1988 and 1992 were visited during a field survey conducted between August 1992 and February 1993. Evidence of the continued presence of gazelle was found at 11 of these locations. All populations were small: estimated population sizes ranged from 5 to 50. In the remaining eight areas it appeared that gazelle had become locally extinct since the last report. Thus gazelle populations appear to be becoming extinct at an alarming rate (eight out of 19, or 42, in five years). The major cause of extinctions and threat to existing populations is illegal hunting. Traditional conservation measures will take time to implement, and may be too late to save most gazelle populations. Instead, protection enforced by a system of auxiliary rangers, recruited from among the local population and working in cooperation with the forces of the local civilian administration, is recommended.

  Resource Type: Journal Papers