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Narrow-range Species (narrow-range + species)
Selected AbstractsPerformance of Sub-Saharan Vertebrates as Indicator Groups for Identifying Priority Areas for ConservationCONSERVATION BIOLOGY, Issue 1 2003Joslin L. Moore Often, these sets of important areas, referred to as priority sets, have been identified through use of data on a single taxon (e.g., birds), which is assumed to act as an indicator for all biodiversity. Using a database of the distributions of 3882 vertebrate species in sub-Saharan Africa, we conducted one of very few large-scale tests of this assumption. We used six potential indicator groups,birds, mammals, amphibians, snakes, threatened birds, and threatened mammals,to find priority sets of 200 areas that best represent the species in that group. Priority sets of grid cells designed to maximize representation of a single indicator group captured 83,93% of species in the other groups. This high degree of representation is consistent with observed high levels of overlap in the patterns of distribution of species in different groups. Those species of highest conservation interest were more poorly represented, however, with only 75,88% of other groups' threatened species and 63,76% of other groups' narrow-range species represented in the priority sets. We conclude that existing priority sets based on indicator groups provide a pragmatic basis for the immediate assessment of priorities for conservation at a continental scale. However, complete and efficient representation,especially of narrow-range species,will not be achieved through indicator groups alone. Therefore, priority-setting procedures must remain flexible so that new areas important for other taxa can be incorporated as data become available. Resumen: La meta de la identificación de prioridades globales y continentales de conservación es la identificación de áreas particularmente valiosas para la conservación en las cuales enfocar esfuerzos más detallados. A menudo, estos conjuntos de áreas importantes (referidas como conjuntos prioritarios) han sido identificados utilizando datos de un solo taxón (e. g. aves), el cual se supone que actúa como indicador de toda la biodiversidad. Utilizando una base de datos de la distribución de 3882 especies de vertebrados en África sub-Sahara, realizamos una de las pocas pruebas a gran escala de este supuesto. Utilizamos seis grupos de indicadores potenciales (aves, mamíferos, anfibios, serpientes, aves amenazadas y mamíferos amenazados ) para encontrar conjuntos prioritarios de 200 áreas que mejor representan las especies de ese grupo. Conjuntos prioritarios de celdas matriciales diseñadas para maximizar la representatividad de un grupo indicador capturaron 83,93% de las especies de los otros grupos. Este alto grado de representatividad es consistente con los altos niveles de superposición observados en los patrones de distribución de especies en los diferentes grupos. Sin embargo, las especies de mayor interés para la conservación estaban poco representadas, con solo 75,88% de las especies amenazadas de otros grupos y 63,76% de las especies de distribución restringida de otros grupos representados en los conjuntos prioritarios. Concluimos que los conjuntos prioritarios existentes, basados en grupos indicadores, proporcionan una base pragmática para la evaluación inmediata de las prioridades de conservación a escala continental. Sin embargo, no se logrará la representación completa y eficiente,especialmente de especies de distribución restringida,solo con grupos indicadores. Por lo tanto, los procedimientos de definición de prioridades deben permanecer flexibles para que se puedan incorporar nuevas áreas importantes para otros taxones a medida que se obtienen los datos. [source] Phytogeographical evidence for post-glacial dispersal limitation of European beech forest speciesECOGRAPHY, Issue 6 2009Wolfgang Willner The post-glacial migration of European beech Fagus sylvatica has been addressed by many studies using either genetic or fossil data or a combination of both. In contrast to this, only little is known about the migration history of beech forest understorey species. In a review of phytosociological literature, we identified 110 plant species which are closely associated with beech forest. We divided the distribution range of European beech forests into 40 geographical regions, and the presence or absence of each species was recorded for each region. We compared overall species numbers per region and numbers of narrow-range species (species present in <10 regions). A multiple regression model was used to test for the explanatory value of three potential diversity controls: range in elevation, soil type diversity, and distance to the nearest potential refuge area. A hierarchical cluster analysis of the narrow-range species was performed. The frequency of range sizes shows a U-shaped distribution, with 42 species occurring in <10 regions. The highest number of beech forest species is found in the southern Alps and adjacent regions, and species numbers decrease with increasing distance from these regions. With only narrow-range species taken into consideration, secondary maxima are found in Spain, the southern Apennines, the Carpathians, and Greece. Distance to the nearest potential refuge area is the strongest predictor of beech forest species richness, while altitudinal range and soil type diversity had little or no predictive value. The clusters of narrow-range species are in good concordance with the glacial refuge areas of beech and other temperate tree species as estimated in recent studies. These findings support the hypothesis that the distribution of many beech forest species is limited by post-glacial dispersal rather than by their environmental requirements. [source] Surrogacy and persistence in reserve selection: landscape prioritization for multiple taxa in BritainJOURNAL OF APPLIED ECOLOGY, Issue 1 2009Aldina M. A. Franco Summary 1A principal goal of protected-area networks is to maintain viable populations of as many species as possible, particularly those that are vulnerable to environmental change outside reserves. Ideally, one wants to be able to protect all biodiversity when selecting priority areas for conservation. 2Using the area-prioritization algorithm ZONATION, we identified the locations where UK Biodiversity Action Plan (BAP) species of mammals, birds, herptiles, butterflies and plants occur in concentrated populations with high connectivity. Both these features are likely to be correlated with population persistence. The analyses were successful in maintaining a high proportion of the connectivity of narrow-range species, and large total amounts of the connectivity of wider-range species over 10% of the land surface of Great Britain. 3Biodiversity Action Plan (BAP , high priority) species of one taxonomic group were not particularly good surrogates (indicators) for BAP species of other taxonomic groups. Hence, maintaining population concentrations of one taxonomic group did not guarantee doing likewise for other taxa. 4Species with narrow geographic ranges were most effective at predicting conservation success for other species, probably because they represent the range of environmental conditions required by other species. 5Synthesis and applications. This study identifies landscape-scale priority areas for conservation of priority species from several taxonomic groups, using the Zonation software. ,Indicator groups' were only partially successful as predictors of priority areas for other taxonomic groups, and therefore, the identification of priority areas for biodiversity conservation should include information from all taxonomic groups available. Larger areas should be protected to account for species not included in the analyses. Conservation solutions based on data for many different species, and particularly those species with narrowly defined ranges, appear to be most effective at protecting other rare taxa. [source] |