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Other Taxonomic Groups (other + taxonomic_groups)
Selected AbstractsFrom Red Lists to Species of Conservation ConcernCONSERVATION BIOLOGY, Issue 6 2004VERENA KELLER aves; conservación de especies; listas rojas; prioridades de conservación; Suiza Abstract:,National red lists of threatened animal and plant species prepared according to the criteria of the World Conservation Union (IUCN) adequately reflect the extinction risk of species within a country but cannot be used directly to set conservation priorities. In particular, the significance of national populations for the conservation of the species as a whole is not taken into account. We present a procedure that can be used to assess national responsibility based on the national red-list status of a species, the international importance of the national population, and the species' "historical rarity" status. We distinguished five responsibility classes for breeding birds: B1, threatened species with internationally important populations in Switzerland; B2, threatened species with internationally less important populations; B3, nonthreatened species with internationally important populations; B4, nonthreatened species with internationally less important populations; and B5, species that have never been common in Switzerland. Two responsibility classes were distinguished for birds occurring in Switzerland as visitors: G1, species with large concentrations in Switzerland and an unfavorable conservation status in Europe, and G2, species with large concentrations in Switzerland and a favorable conservation status in Europe. Two additional classes (G3 and G4) for visiting species occurring in internationally less important numbers are possible but were not analyzed in detail. Responsibility classes B1, B2, B3, G1, and G2 were defined as species of national conservation concern. We developed the method for birds in Switzerland, but it can be used in other countries and for other taxonomic groups as well. It is particularly suitable where national red lists are established according to IUCN guidelines. Resumen:,Las listas rojas nacionales de especies de animales y plantas amenazadas que siguen los criterios de la World Conservation Union (IUCN) reflejan adecuadamente el riesgo de extinción de especies en un país pero no pueden ser utilizadas directamente para definir prioridades de conservación. En particular, no se toma en cuenta el significado de poblaciones nacionales para la conservación de especies como tales. Presentamos un procedimiento que se puede utilizar para evaluar la responsabilidad nacional con base en el estatus de lista roja de una especie en un país, la importancia internacional de la población nacional y el estatus de "rareza histórica" de la especie. Distinguimos cinco clases de responsabilidad para aves residentes: B1, especies amenazadas con poblaciones internacionalmente importantes en Suiza; B2, especies amenazadas con poblaciones internacionalmente menos importantes; B3, especies no amenazadas con poblaciones internacionalmente importantes; B4, especies no amenazadas con poblaciones internacionalmente menos importantes; y B5, especies que nunca han sido comunes en Suiza. Se distinguieron dos clases de responsabilidad para aves que ocurren como visitantes en Suiza: G1, especies con grandes concentraciones en Suiza y un estatus de conservación desfavorable en Europa y G2, especies con grandes concentraciones en Suiza y un estatus de conservación favorable en Europa. Son posibles dos clases más, (G3 y G4) para especies visitantes que ocurren en números menos importantes internacionalmente, pero no fueron analizados en detalle. Las clases de responsabilidad B1, B2, B3, G1 y G2 fueron definidas como especies de interés nacional para la conservación. Desarrollamos el método para aves en Suiza, pero también se puede utilizar en otros países y con otros grupos taxonómicos, Es particularmente adecuado donde las listas rojas nacionales se establecen de acuerdo con lineamientos de IUCN. [source] EMPIRICAL EVIDENCE FOR AN OPTIMAL BODY SIZE IN SNAKESEVOLUTION, Issue 2 2003Scott M. Boback Abstract The concept of optimal size has been invoked to explain patterns in body size of terrestrial mammals. However, the generality of this phenomenon has not been tested with similarly complete data from other taxonomic groups. In this study we describe three statistical patterns of body size in snakes, all of which indicate an optimal length of 1.0 m. First, a distribution of largest body lengths of 618 snake species had a single mode at 1.0 m. Second, we found a positive relationship between the size of the largest member of an island snake assemblage and island area and a negative relationship between the size of the smallest member of an island snake assemblage and island area. Best-fit lines through these data cross at a point corresponding to 1.0 m in body length, the presumed optimal size for a one-species island. Third, mainland snake species smaller than 1.0 m become larger on islands whereas those larger than 1.0 m become smaller on islands. The observation that all three analyses converge on a common body size is concordant with patterns observed in mammals and partial analyses of four other disparate animal clades. Because snakes differ so strikingly from mammals (ectotherms, gape-limited predators, elongate body shape) the concordant patterns of these two groups provide strong evidence for the evolution of an optimal body size within independent monophyletic groups. However, snakes differ from other taxonomic groups that have been studied in exhibiting a body size distribution that is not obviously skewed in either direction. We suggest that idiosyncratic features of the natural history of ectotherms allow relatively unconstrained distributions of body size whereas physiological limitations of endotherms constrain distributions of body size to a right skew. [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] Species richness and structure of three Neotropical bat assemblagesBIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 3 2008KATJA REX We compared the assemblages of phyllostomid bats in three Neotropical rainforests with respect to species richness and assemblage structure and suggested a method to validate estimates of species richness for Neotropical bat assemblages based on mist-netting data. The fully inventoried bat assemblage at La Selva Biological Station (LS, 100 m elevation) in Costa Rica was used as a reference site to evaluate seven estimators of species richness. The Jackknife 2 method agreed best with the known bat species richness and thus was used to extrapolate species richness for an Amazonian bat assemblage (Tiputini Biodiversity Station; TBS, 200 m elevation) and an Andean premontane bat assemblage (Podocarpus National Park; BOM, 1000 m elevation) in Ecuador. Our results suggest that more than 100 bat species occur sympatrically at TBS and about 50 bat species coexist at BOM. TBS harbours one of the most species-rich bat assemblages known, including a highly diverse phyllostomid assemblage. Furthermore, we related assemblage structure to large-scale geographical patterns in floral diversity obtained from botanical literature. Assemblage structure of these three phyllostomid assemblages was influenced by differences in floral diversity at the three sites. At the Andean site, where understorey shrubs and epiphytes exhibit the highest diversity, the phyllostomid assemblage is mainly composed of understorey frugivores and nectarivorous species. By contrast, canopy frugivores are most abundant at the Amazonian site, coinciding with the high abundance of canopy fruiting trees. Assemblage patterns of other taxonomic groups also may reflect the geographical distribution patterns of floral elements in the Andean and Amazonian regions. © 2008 The Linnean Society of London, Biological Journal of the Linnean Society, 2008, 94, 617,629. [source] | ||||||||||