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Endangered Species (endangered + species)
Terms modified by Endangered Species Selected AbstractsDiscrepancies in Reported Levels of International Wildlife TradeCONSERVATION BIOLOGY, Issue 6 2005ARTHUR G. BLUNDELL aduanas; CITES; especies en peligro; programa de aranceles armonizados Abstract:,The international wildlife trade is a principal cause of biodiversity loss, involving hundreds of millions of plants and animals each year, yet wildlife trade records are notoriously unreliable. We assessed the precision of wildlife trade reports for the United States, the world's largest consumer of endangered wildlife, by comparing data from the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) with U.S. Customs data. For both U.S. imports and exports, CITES and Customs reported substantially different trade volumes for all taxa in all years. Discrepancies ranged from a CITES-reported volume 376% greater than that reported by Customs (live coral imports, 2000) to a Customs' report 5202% greater than CITES (conch exports, 2000). These widely divergent data suggest widespread inaccuracies that may distort the perceived risk of targeted wildlife exploitation, leading to misallocation of management resources and less effective conservation strategies. Conservation scientists and practitioners should reexamine assumptions regarding the significance of the international wildlife trade. Resumen:,El comercio internacional de vida silvestre es una causa principal de la pérdida de biodiversidad, ya que involucra a cientos de millones de plantas y animales cada año; no obstante eso, los registros del comercio son notoriamente poco confiables. Evaluamos la precisión de los registros de comercio de vida silvestre de Estados Unidos, el mayor consumidor de vida silvestre en peligro en el mundo, mediante la comparación de datos del Convenio Internacional para el Comercio de Especies de Flora y Fauna Silvestre en Peligro (CITES) con datos de la Aduana de E.U.A. Tanto para importaciones como exportaciones, CITES y Aduana reportaron volúmenes de comercio de todos los taxa sustancialmente diferentes en todos los años. Las discrepancias abarcaron desde un volumen reportado por CITES 376% más grande que el reportado por la Aduana (importaciones de coral vivo, 2000) hasta un reporte de la Aduana 5202% mayor que el de CITES (exportaciones de caracol, 2000). Estos datos ampliamente divergentes sugieren imprecisiones generalizadas que pueden distorsionar el riesgo percibido por la explotación de vida silvestre, lo que conducirá a la incorrecta asignación de recursos para la gestión y a estrategias de conservación menos efectivas. Los científicos y profesionales de la conservación deberían reexaminar sus suposiciones respecto al significado del comercio internacional de vida silvestre. [source] Private Property and Public Benefit: Habitat Conservation Planning for Endangered SpeciesCONSERVATION BIOLOGY, Issue 1 2000Gregory A. Thomas No abstract is available for this article. [source] Primates in traditional folk medicine: a world overviewMAMMAL REVIEW, Issue 2 2010Rômulo R. N. ALVES ABSTRACT 1Almost 50% of primate species are in danger of becoming extinct, according to the criteria of the International Union for Conservation of Nature (IUCN) Red List of Threatened Species. This is partly because of their consumption by humans. The reasons for hunting vary by region. One pretext is the medicinal or magical value of products derived from these animals. 2In this paper, we provide an overview of the global use of primates in traditional folk medicines as well as identifying the species used as remedies associated with folk beliefs. Some important questions relating to the conservation of primates are addressed. 3Our results revealed that at least 101 species of primates, which belong to 38 genera and 10 families, were used in traditional folk practices and in magic,religious rituals throughout the world. 4Of the 101 species of primates recorded in our review, 12 species were classified as Critically Endangered, 23 as Endangered, 22 as Vulnerable, seven as Near Threatened, 36 as Least Concern and one as Data Deficient in the IUCN Red List. All species were also included in The Convention on International Trade in Endangered Species of Wild Fauna and Flora Appendices I or II, although the reasons for their inclusion were not necessarily related to their medicinal use. 5The widespread utilization of primates in traditional medicine is evidence of the importance of understanding such uses in the context of primate conservation as well as the need for considering socio-cultural factors when establishing management plans concerning the sustainable use of these mammals. [source] Genetic tracking of basking shark products in international tradeANIMAL CONSERVATION, Issue 2 2007J. E. Magnussen Abstract Mounting evidence that sharks are being over-fished to supply shark fin markets is causing widespread concern about the sustainability of these practices. The basking shark Cetorhinus maximus, whose fins command high market prices, has proven especially sensitive to exploitation. To prevent further population declines, this species is now protected in the territorial waters of several countries, and is listed on Appendix II of the Convention on International Trade in Endangered Species (CITES) requiring monitoring of trade in its products by all parties to CITES. Tracking trade in basking shark products, however, is often hampered by difficulties in identifying shark products to species of origin. Here, we present the development and application of a streamlined genetic forensics assay that does not require DNA sequencing to identify basking shark products. The dual-primer, species-specific polymerase chain reaction strategy provides diagnostic redundancy for robustness in legal venues. It is also effective for identifying basking shark products regardless of geographic origin, an important consideration, given the global distribution of the species and international sourcing of fins to the trade. Application of the assay confirmed the presence of basking shark fins in the Hong Kong and Japan markets, and indicated an apparent relationship between the Chinese fin trader category ,Nuo Wei Tian Jiu' and fins from basking sharks. The assay was also used in a law enforcement investigation to document illegal trade in basking shark fins in the United States where this species is prohibited from harvest and trade. These trade detections suggest that the high market value of basking shark fins is continuing to drive the exploitation, surreptitious and otherwise, of this highly threatened species, underscoring the need for improved trade monitoring. The streamlined assay developed here can assist in monitoring and conservation on a worldwide scale. [source] Preservation causes shrinkage in seahorses: implications for biological studies and for managing sustainable trade with minimum size limitsAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 4 2009Julie L. Nadeau Abstract 1.The implications of shrinkage associated with desiccation and ethanol preservation for seahorses (genus Hippocampus) were investigated using Hippocampus guttulatus (European long-snouted seahorse) as a model. Specifically, this research addressed the implications of preservation for taxonomy and life history studies and the application of minimum size limits (MSL) for managing seahorse trade. 2.In 2004, the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) listed all seahorse species on its Appendix II, and recommended a 10,cm MSL as an interim means of ensuring sustainable international trade. Inconsistencies in seahorse measurement methods and repeatability posed challenges for applying the MSL. Moreover, the shrinking effect of desiccation on body length observed in other fish was assumed to be negligible for seahorses because of their high degree of ossification. 3.Changes in seahorse sizes were measured following immersion in ethanol and desiccation. H. guttulatus shrank on average by 0.1,2.3% when preserved in ethanol and 3.0,6.4% when dried, depending on the trait measured. Similar trends were observed in a sample of H. kuda (yellow seahorse). Specimen posture during drying, and measurement methods also influenced estimates of size. 4.Based on the shrinkage observed, 14,44% of captured seahorses that are dried could shrink to below the recommended MSL, even if all seahorses were longer than the MSL at capture. This demonstrates that small changes in body lengths can have significant implications for trade of species managed with size limits. 5.Recommendations are to (1) standardize seahorse measurement methods, (2) consider the effects of preservation and measurement technique on body lengths, and apply appropriate corrections in comparative studies and when developing fisheries management strategies, and (3) adjust size limits at the point of capture to ensure retained seahorses comply with the CITES recommended MSL. Copyright © 2008 John Wiley & Sons, Ltd. [source] Wildlife trade and endangered species protectionAUSTRALIAN JOURNAL OF AGRICULTURAL & RESOURCE ECONOMICS, Issue 4 2004Paul C. Missios Markets for endangered species potentially generate incentives for both legal supply and poaching. To deter poaching, governments can spend on enforcement or increase legal harvesting to reduce the return from poaching. A leader,follower commitment game is developed to examine these choices in the presence of illegal harvesting and the resulting impacts on species stocks. In addition, current trade restrictions imposed under the Convention on International Trade in Endangered Species of Wild Fauna and Flora are examined. With Cournot conjectures among poachers, the model details the subgame perfect equilibrium interactions between poaching levels, enforcement and legal harvesting. [source] Endangered species traded on-line.AUSTRALIAN VETERINARY JOURNAL, Issue 9 2005Mark Thornley No abstract is available for this article. [source] Phylogenetic Comparative Methods Strengthen Evidence for Reduced Genetic Diversity among Endangered TetrapodsCONSERVATION BIOLOGY, Issue 5 2010PATRICK A. FLIGHT evolución de la historia de vida; extinción; heterocigosidad de proteínas; regresión filogenética; tamaño poblacional efectivo Abstract:,The fitness of species with little genetic diversity is expected to be affected by inbreeding and an inability to respond to environmental change. Conservation theory suggests that endangered species will generally demonstrate lower genetic diversity than taxa that are not threatened. This hypothesis has been challenged because the time frame of anthropogenic extinction may be too fast to expect genetic factors to significantly contribute. I conducted a meta-analysis to examine how genetic diversity in 894 tetrapods correlates with extinction threat level. Because species are not evolutionarily independent, I used a phylogenetic regression framework to address this issue. Mean genetic diversity of tetrapods, as assessed by protein heterozygosity, was 29.7,31.5% lower on average in threatened species than in their nonthreatened relatives, a highly significant reduction. Within amphibians as diversity decreased extinction risk increased in phylogenetic models, but not in nonphylogenetic regressions. The effects of threatened status on diversity also remained significant after accounting for body size in mammals. These results support the hypothesis that genetic effects on population fitness are important in the extinction process. Resumen:,Se espera que la adaptabilidad de una especie con poca diversidad genética sea afectada por la endogamia y una incapacidad para responder a cambios ambientales. La teoría de la conservación sugiere que las especies en peligro generalmente muestran menor diversidad genética que taxa que no están amenazados. Esta hipótesis ha sido cuestionada porque el período de tiempo de la extinción antropogénica puede ser muy rápido para esperar que los factores genéticos contribuyan significativamente. Realice un meta-análisis para examinar cómo se correlaciona la diversidad genética de 894 tetrápodos con el nivel de amenaza de extinción. Debido a que las especies no son independientes evolutivamente, utilice un marco de regresión filogenética para abordar este tema. La media de la diversidad genética de tetrápodos, medida como la heterocigosidad de proteínas, fue 29.7,31.5% menor en las especies amenazadas que en sus parientes no amenazados, una reducción altamente significativa. En anfibios, a medida que disminuía la diversidad el riesgo de extinción incrementaba en los modelos filogenéticos, pero no en las regresiones no filogenéticas. El efecto del estatus de amenaza sobre la biodiversidad también permaneció significativo después de considerar el tamaño corporal de mamíferos. Estos resultados dan soporte a la hipótesis de que los efectos genéticos sobre la adaptabilidad de la población son importantes en el proceso de extinción. [source] Conservation Biology in Asia: the Major Policy ChallengesCONSERVATION BIOLOGY, Issue 4 2009JEFFREY A. McNEELY Asia; bosques; comercio de vida silvestres; conflicto humano-animal; economía Abstract:,With about half the world's human population and booming economies, Asia faces numerous challenges to its biodiversity. The Asia Section of the Society for Conservation Biology has identified some key policy issues in which significant progress can be made. These include developing new sources of funding for forest conservation; identifying potential impacts of energy alternatives on the conservation of biodiversity; curbing the trade in endangered species of plants and animals; a special focus on the conservation of mountain biodiversity; enhancing relevant research; ensuring that conservation biology contributes to major international conventions and funding mechanisms; using conservation biology to build a better understanding of zoonotic diseases; more effectively addressing human,animal conflicts; enhancing community-based conservation; and using conservation biology to help address the pervasive water-deficit problems in much of Asia. These challenges can be met through improved regional cooperation among the relevant stakeholders. Resumen:,Con aproximadamente la mitad de la población humana y economías prósperas, Asia enfrenta numerosos retos para su biodiversidad. La sección Asia de la Sociedad para la Biología de la Conservación ha identificado algunos temas políticos claves en los que se puede hacer un progreso significativo. Estos incluyen el desarrollo de nuevas fuentes de financiamiento para la conservación de bosques; la identificación de impactos potenciales de las energías alternativas sobre la conservación de la biodiversidad; reducción del comercio de especies de animales y plantas en peligro; un enfoque especial en la conservación de la biodiversidad montana; promoción de investigación relevante; garantía de que la biología de la conservación contribuye a convenios internacionales y mecanismos de financiamiento; utilización de la biología de la conservación para lograr un mejor entendimiento de enfermedades zoonóticas; mejor atención a los conflictos humanos-animales; reforzamiento de la conservación basada en comunidades y utilización de la biología de la conservación para atender los problemas de déficit de agua en gran parte de Asia. Estos retos se pueden atender mediante una mejor cooperación regional entre los principales actores. [source] Pacific Salmon Extinctions: Quantifying Lost and Remaining DiversityCONSERVATION BIOLOGY, Issue 4 2007RICHARD G. GUSTAFSON biodiversidad; diversidad de salmones; extinción de poblaciones; historia de vida de salmones Abstract:,Widespread population extirpations and the consequent loss of ecological, genetic, and life-history diversity can lead to extinction of evolutionarily significant units (ESUs) and species. We attempted to systematically enumerate extinct Pacific salmon populations and characterize lost ecological, life history, and genetic diversity types among six species of Pacific salmon (Chinook [Oncorhynchus tshawytscha], sockeye [O. nerka], coho [O. kisutch], chum [O. keta], and pink salmon [O. gorbuscha] and steelhead trout [O. mykiss]) from the western contiguous United States. We estimated that, collectively, 29% of nearly 1400 historical populations of these six species have been lost from the Pacific Northwest and California since Euro-American contact. Across all species there was a highly significant difference in the proportion of population extinctions between coastal (0.14 extinct) and interior (0.55 extinct) regions. Sockeye salmon (which typically rely on lacustrine habitats for rearing) and stream-maturing Chinook salmon (which stay in freshwater for many months prior to spawning) had significantly higher proportional population losses than other species and maturation types. Aggregate losses of major ecological, life-history, and genetic biodiversity components across all species were estimated at 33%, 15%, and 27%, respectively. Collectively, we believe these population extirpations represent a loss of between 16% and 30% of all historical ESUs in the study area. On the other hand, over two-thirds of historical Pacific salmon populations in this area persist, and considerable diversity remains at all scales. Because over one-third of the remaining populations belong to threatened or endangered species listed under the U.S. Endangered Species Act, it is apparent that a critical juncture has been reached in efforts to preserve what remains of Pacific salmon diversity. It is also evident that persistence of existing, and evolution of future, diversity will depend on the ability of Pacific salmon to adapt to anthropogenically altered habitats. Resumen:,Las extirpaciones generalizadas de poblaciones y la consecuente pérdida de diversidad ecológica, genética y de historia natural puede llevar a la extinción de unidades evolutivamente significativas (UES) y especies. Intentamos enumerar sistemáticamente a las poblaciones extintas de salmón del Pacífico y caracterizar a los tipos de diversidad ecológica, de historia natural y genética de seis especies de salmón del Pacífico Oncorhynchus tshawytscha, O. nerka, O. kisutch, O. keta, y O. gorbuscha; y trucha O. mykiss en el occidente de Estados Unidos. Estimamos que, colectivamente, se ha perdido a 29% de casi 1400 poblaciones históricas de estas seis especies en el Pacífico Noroeste y California desde la colonización europea. En todas las especies hubo una diferencia altamente significativa en la proporción de extinción de poblaciones entre regiones costeras (0.14 extintas) e interiores (0.55 extintas). O. nerka (que típicamente cría en hábitats lacustres) y O. tshawytscha (que permanece en agua dulce por muchos meses antes del desove) tuvieron pérdidas poblacionales significativamente mayores que las otras especies y tipos de maduración. Se estimó que las pérdidas agregadas de componentes mayores de la biodiversidad ecológica, de historia natural y genética en todas las especies fueron de 33%, 15% y 27%, respectivamente. Colectivamente, consideramos que estas extirpaciones de poblaciones representan una pérdida entre 16% y 30% de todas las UES históricas en el área de estudio. Por otro lado, más de dos tercios de las poblaciones históricas de salmón del Pacífico persisten en esta área, y aun hay considerable diversidad en todas las escalas. Debido a que más de un tercio de las poblaciones restantes pertenecen a especies enlistadas como amenazadas o en peligro en el Acta de Especies en Peligro de E. U. A., es evidente que se ha llegado a una disyuntiva crítica en los esfuerzos para preservar lo que queda de la diversidad de salmón del Pacífico. También es evidente que la persistencia de la diversidad existente, y su futura evolución, dependerá de la habilidad del salmón del Pacífico para adaptarse a hábitats alterados antropogénicamente. [source] The Conservation Relevance of Epidemiological Research into Carnivore Viral Diseases in the SerengetiCONSERVATION BIOLOGY, Issue 3 2007SARAH CLEAVELAND conservación de carnívoros; investigación epidemiológica; moquillo; rabia; Serengeti Abstract:,Recent outbreaks of rabies and canine distemper in wildlife populations of the Serengeti show that infectious disease constitutes a significant cause of mortality that can result in regional extirpation of endangered species even within large, well-protected areas. Nevertheless, effective management of an infectious disease depends critically on understanding the epidemiological dynamics of the causative pathogen. Pathogens with short infection cycles cannot persist in small populations in the absence of a more permanent reservoir of infection. Development of appropriate interventions requires detailed data on transmission pathways between reservoirs and wildlife populations of conservation concern. Relevant data can be derived from long-term population monitoring, epidemic and case-surveillance patterns, genetic analyses of rapidly evolving pathogens, serological surveys, and intervention studies. We examined studies of carnivore diseases in the Serengeti. Epidemiological research contributes to wildlife conservation policy in terms of management of endangered populations and the integration of wildlife conservation with public health interventions. Long-term, integrative, cross-species research is essential for formulation of effective policy for disease control and optimization of ecosystem health. Resumen:,Brotes recientes de rabia y moquillo en poblaciones silvestres del Serengeti muestran que las enfermedades infecciosas constituyen una causa significativa de mortandad que puede resultar en la extirpación regional de especies en peligro, aun en áreas extensas bien protegidas. Sin embargo, el manejo efectivo de una enfermedad infecciosa depende críticamente del entendimiento de la dinámica epidemiológica del patógeno. Los patógenos con ciclo infeccioso corto no pueden persistir en poblaciones pequeñas en ausencia de un reservorio de la infección más permanente. El desarrollo de intervenciones adecuadas requiere de datos detallados de las vías de transmisión entre reservorios y poblaciones de vida silvestre de preocupación para la conservación. Se pueden derivar datos importantes del monitoreo de poblaciones a largo plazo, de patrones de epidemias y de estudios de caso, del análisis genético de patógenos que evolucionan rápidamente, de muestreos sexológicos y de estudios de intervención. Examinamos estudios de enfermedades de carnívoros en el Serengeti. La investigación epidemiológica contribuye a las políticas de conservación de vida silvestre en términos de la gestión de poblaciones en peligro y de la integración de la conservación con intervenciones de salud pública. La investigación a largo plazo e integradora es esencial para la formulación de políticas efectivas para el control de enfermedades y la optimización de la salud del ecosistema. [source] On the Compatibility of a Conservation Ethic with Biological ScienceCONSERVATION BIOLOGY, Issue 2 2007MARK SAGOFF Darwinismo; estética; ética de conservación; teología Abstract:,If value entails or implies purpose, it follows that natural objects (e.g., endangered species) lack value and thus cannot be worth protecting except for a purpose they may serve,either the end for which God created the world (according to natural theology) or some use to which human beings may put them (according to a consequentialist or utilitarian ethic). If value requires purpose, the refutation of natural theology after Darwin implies that humanity has no obligation to respect or preserve the natural world except insofar as it is economically efficient to do so. Drawing on the distinction between explanation and communication found in Calvinist theology, I argue that value does not entail purpose. The expressive, aesthetic, or communicative aspects of nature may be valuable or endow natural objects with value apart from any use or purpose these objects may serve. The crucial distinction between explanation and communication,one scientific, the other aesthetic,offers a rationale for an obligation to protect the natural world that may appeal to members of faith communities and to biologists and other scientists. This approach also helps resolve the "lurking inconsistency" some scholars see in the relationship between a deterministic biological science and a conservationist ethic. Resumen:,Si el valor conlleva o implica propósito, se entiende que los objetos naturales (e.g., especies en peligro) carecen de valor y por lo tanto no merecen ser protegidos excepto porque pueden servir para el fin por el que Dios creó al mundo (de acuerdo con la teología natural) o para algún uso asignado por humanos (de acuerdo con la ética consecuentalista o utilitaria). Si el valor requiere propósito, la refutación de la teología natural después de Darwin implica que la humanidad no tiene obligación para respetar o preservar el mundo natural excepto si es económicamente eficiente hacerlo. Con base en la distinción entre explicación y comunicación encontrada en la teología Calvinista, argumento que el valor no implica propósito. Los aspectos expresivos, estéticos o comunicativos de la naturaleza pueden ser valiosos o proveer valor a los objetos naturales independientemente de cualquier uso o propósito que puedan tener estos objetos. La distinción crucial entre explicación y comunicación,una científica y la otra estética,ofrece un fundamento para la obligación de proteger el mundo natural que pueda interesar a miembros de comunidades religiosas, a biólogos y otros científicos. Este método también ayuda a resolver la "inconsistencia al acecho" en la relación entre una ciencia biológica determinista y una ética conservacionista que algunos académicos ven. [source] Area-Based Refinement for Selection of Reserve Sites with the Benefit-Function ApproachCONSERVATION BIOLOGY, Issue 2 2007ANNI ARPONEN algoritmo de selección de sitios; persistencia; peso de especies; relaciones especies-área; selección de reservas Abstract:,Optimization of resource use is necessary for efficient conservation planning. Many reserve-selection algorithms aim to identify representative but inexpensive networks, which may lead to selecting small sites due to their lower costs and collectively higher species richness. Nevertheless, larger sites would be preferable regarding species' long-term persistence. An area-based refinement can be used to overcome this problem. We used a reserve-planning framework in which continuous benefit functions valued representation (numbers of populations), and differential species weights were based on a species' local rarity and threatened status. We introduced a refinement based on the species-area relationship that provides relatively higher values for larger sites. We applied the proposed method to rich fen vegetation in southern Finland. The species-area refinement resulted in a network of significantly larger sites with minor trade-offs with representation (numbers of populations). Giving endangered species higher weights ensured that the trade-off occurred mostly between site size and representation of low-priority species. We recommend using a species-area refinement for practical, maximum-coverage conservation planning. Resumen:,La optimización del uso de recursos es necesaria para la planificación eficiente de la conservación. Muchos algoritmos para la selección de reservas tratan de identificar redes representativas pero poco costosas, que pueden conducir a la selección de sitios pequeños debido a sus costos menores y mayor riqueza de especies colectiva. Sin embargo, los sitios grandes serían preferibles para la persistencia de las especies a largo plazo. Para sobreponerse a este problema se puede utilizar un refinamiento basado en el área. Utilizamos un marco de referencia para la planificación de reservas en el que las funciones de beneficio continuas valoraron la representación (número de poblaciones), y los pesos diferenciales de las especies se basaron en la rareza local de una especie y en su estatus de amenaza. Introdujimos un refinamiento basado en la relación especies-área que proporciona valores relativamente mayores a los sitios grandes. Aplicamos el método propuesto a la rica vegetación de ciénegas en el sur de Finlandia. El refinamiento de las especies-área resultó en una red de sitios significativamente más grandes con desequilibrios menores en la representación (número de poblaciones). La asignación de valores más altos a las especies en peligro aseguró que el desequilibrio ocurriera principalmente entre el tamaño del sitio y la representación de especies de prioridad baja. Recomendamos la utilización de de un refinamiento de especies-área para una planificación de la conservación de cobertura máxima. [source] The Journal of the Society for Conservation Biology A global community of conservation professionalsCONSERVATION BIOLOGY, Issue 2 2006Article first published online: 27 MAR 200 Cover: Old-growth forest of the Hoh River Valley, Olympic National Park, Washington (U.S.A.). For decades the U.S. Pacific Norwest has been a center of controversy over logging and endangered species. This special section explores progress made by the Northwest Forest Plan,a global example of land-use planning,a decade after it was established to end the stalemate over logging and endangered species. Authors include some of the key architects involved in its creation and implementation. Photo by Kevin Schafer. See pages 274,374. [source] A Freshwater Classification Approach for Biodiversity Conservation PlanningCONSERVATION BIOLOGY, Issue 2 2005JONATHAN V. HIGGINS biodiversidad de agua dulce; clasificación; planificación de conservación; representativo Abstract:,Freshwater biodiversity is highly endangered and faces increasing threats worldwide. To be complete, regional plans that identify critical areas for conservation must capture representative components of freshwater biodiversity as well as rare and endangered species. We present a spatially hierarchical approach to classify freshwater systems to create a coarse filter to capture representative freshwater biodiversity in regional conservation plans. The classification framework has four levels that we described using abiotic factors within a zoogeographic context and mapped in a geographic information system. Methods to classify and map units are flexible and can be automated where high-quality spatial data exist, or can be manually developed where such data are not available. Products include a spatially comprehensive inventory of mapped and classified units that can be used remotely to characterize regional patterns of aquatic ecosystems. We provide examples of classification procedures in data-rich and data-poor regions from the Columbia River Basin in the Pacific Northwest of North America and the upper Paraguay River in central South America. The approach, which has been applied in North, Central, and South America, provides a relatively rapid and pragmatic way to account for representative freshwater biodiversity at scales appropriate to regional assessments. Resumen:,La biodiversidad de agua dulce está en peligro y enfrenta amenazas crecientes en todo el mundo. Para ser completos, los planes regionales que identifican áreas críticas para la conservación deben incluir componentes representativos de la biodiversidad de agua dulce así como especies raras y en peligro. Presentamos un método espacialmente jerárquico para clasificar sistemas de agua dulce para crear un filtro grueso que capte a la biodiversidad de agua dulce en los planes regionales de conservación. La estructura de la clasificación tiene cuatro niveles que describimos utilizando factores abióticos en un contexto zoogeográfico y localizamos en un sistema de información geográfico. Los métodos para clasificar y trazar mapas son flexibles y pueden ser automatizados, donde existen datos espaciales de alta calidad, o desarrollados manualmente cuando tales datos no están disponibles. Los productos incluyen un inventario completo de unidades mapeadas y clasificadas que pueden ser usadas remotamente para caracterizar patrones regionales de ecosistemas acuáticos. Proporcionamos ejemplos de procedimientos de clasificación en regiones ricas y pobres en datos en la cuenca del Río Columbia en el noroeste de Norte América y del Río Paraguay en Sudamérica central. El método, que ha sido aplicado en Norte, Centro y Sudamérica, proporciona una forma relativamente rápida y pragmática de contabilizar biodiversidad de agua dulce representativa en escalas adecuadas para evaluaciones regionales. [source] A Quantitative Conservation Approach for the Endangered Butterfly Maculinea alconCONSERVATION BIOLOGY, Issue 2 2004MICHIEL F. WallisDeVries The quality and size of habitat patches and their isolation from other patches are the main parameters for an assessment of population persistence, but translating persistence probabilities into practical measures is still a weak link in conservation management. I provide a quantitative conservation approach for the endangered myrmecophilous butterfly Maculinea alcon in the Netherlands. All 127 colonies known on heathland since 1990 were investigated for patch quality, size, and isolation. I assessed habitat quality in three 10 × 10 m plots for most colonies. Site occupancy in 1998,1999 was only 56%. Occupancy was best explained by a logistic regression including patch area, host ant presence, host plant abundance, overall heathland area, and connectivity between sites ( R2= 0.410, p < 0.0001); it correctly classified the occupied or vacant status for 82% of the sites. Connectivity contributed only 3.6% to the total explained variation of site occupancy, indicating that habitat characteristics were more important than isolation in determining population persistence at the examined scale level (>500 m). Grazing and sod cutting had a beneficial impact, but in combination these practices proved detrimental. Hydrological measures to prevent drainage were also associated with lowered occupancy. I used the different components in the logistic regression to formulate objective management recommendations. These consisted of sod cutting, reduction of management intensity, enlargement of habitat, or combinations of these recommendations. The results highlight the importance of careful management when site quality is determined by multiple factors. The quantitative conservation approach followed here can be fruitfully extended to other endangered species, provided enough is known about their ecological requirements and how management actions affect them. Resumen:,La preservación de fragmentos individuales es extremadamente importante para especies en peligro con capacidad de dispersión limitada. La calidad y tamaño de los fragmentos de hábitat y su aislamiento de otros fragmentos son los parámetros principales para la evaluación de la persistencia de la población, pero la traducción de probabilidades de persistencia en medidas prácticas aun es un eslabón débil en la gestión de conservación. Proporciono un método cuantitativo de conservación para la mariposa mirmecófila Maculinea alcon en peligro en Holanda. Se investigó a las 127 colonias conocidas en brezales desde 1990 para calidad, tamaño y aislamiento del fragmento. Evalué la calidad del hábitat en tres parcelas de 10 × 10 m en la mayoría de las colonias. La ocupación de sitios en 1998-1999 fue sólo 56%. La ocupación fue mejor explicada por regresión logística incluyendo la superficie del fragmento, presencia de hormigas huésped, abundancia de plantas huésped, superficie total del brezal y conectividad entre sitios ( R2= 0.410, p < 0.0001); clasificó el estatus de ocupado o vacante en 82% de los sitios. La conectividad contribuyó con solo 36% de la variación total de sitio de ocupación, lo que indica que las características de hábitat fueron más importantes que el aislamiento en la determinación de la persistencia de la población en el nivel de escala examinado (>500 m). El pastoreo y el corte de pasto tuvieron un impacto benéfico pero combinadas, estas prácticas fueron perjudiciales. Obras hidrológicas para prevenir la desecación también se asociaron con una disminución en la ocupación. Utilicé los diferentes componentes de la regresión logística para formular recomendaciones objetivas de gestión. Estas incluyeron el corte de pasto, reducción en la intensidad de manejo, aumento de hábitat o combinaciones de estas recomendaciones. Los resultados resaltan la importancia de la gestión cuidadosa cuando la calidad del sitio está determinada por múltiples factores. El método cuantitativo de preservación utilizado puede ser extendido exitosamente a otras especies en peligro, siempre que sean suficientemente conocidos sus requerimientos ecológicos y la forma en que le afectan las acciones de manejo. [source] Migration of hawksbill turtles Eretmochelys imbricata from Tortuguero, Costa RicaECOGRAPHY, Issue 3 2005Sebastian Troëng The hawksbill turtle Eretmochelys imbricata is a widely distributed and critically endangered species that feeds on sponges and fills an important ecological role in the coral reef ecosystem. At Tortuguero, Costa Rica, trend analyses indicate considerable decline in nesting estimated at 77.2,94.5% between 1956 and 2003, as a result of excessive turtle fishing. We analyzed flipper tag returns, satellite telemetry and genetic samples to determine movements and habitat use of adult female Tortuguero hawksbills. Tag returns and satellite telemetry show hawksbills migrate to foraging grounds in Nicaragua and Honduras. Genetic analysis indicates the hawksbills may also migrate to Cuban, Puerto Rican, and possibly Mexican waters. We conclude hawksbills represent an internationally shared resource. There is a close correlation between tag recapture sites, hawksbill foraging grounds and coral reef distribution. Caribbean coral reef decline may reduce food availability and negatively impact hawksbill turtles. Conversely, hawksbill decline may shift the balance on coral reefs by reducing predation pressure on sponges and hence make coral reefs less resilient to natural and anthropogenic threats. Strategies aiming to conserve hawksbills and coral reefs must consider both the extensive hawksbill migrations and the close relationship between the species and the coral reef ecosystem. [source] Mixed biodiversity benefits of agri-environment schemes in five European countriesECOLOGY LETTERS, Issue 3 2006D. Kleijn Abstract Agri-environment schemes are an increasingly important tool for the maintenance and restoration of farmland biodiversity in Europe but their ecological effects are poorly known. Scheme design is partly based on non-ecological considerations and poses important restrictions on evaluation studies. We describe a robust approach to evaluate agri-environment schemes and use it to evaluate the biodiversity effects of agri-environment schemes in five European countries. We compared species density of vascular plants, birds, bees, grasshoppers and crickets, and spiders on 202 paired fields, one with an agri-environment scheme, the other conventionally managed. In all countries, agri-environment schemes had marginal to moderately positive effects on biodiversity. However, uncommon species benefited in only two of five countries and species listed in Red Data Books rarely benefited from agri-environment schemes. Scheme objectives may need to differentiate between biodiversity of common species that can be enhanced with relatively simple modifications in farming practices and diversity or abundance of endangered species which require more elaborate conservation measures. [source] Pesticide residues in the aquatic environment of banana plantation areas in the North Atlantic Zone of Costa RicaENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 8 2000Luisa E. Castillo Abstract A study of pesticide residues in surface waters and sediments was undertaken in the Suerte River Basin, Costa Rica, that drains into the Tortuguero conservation area. Samples were collected in streams, packing plants, and the Suerte River. The most frequently measured compounds in surface water samples were the fungicides thiabendazole, propiconazole, and imazalil; the nematicides terbufos and cadusafos; and the insecticide chlorpyrifos. At the conservation area, propiconazole was detected in 43% of the samples at concentrations ranging from 0.05 to 1.0 ,g/L. In 25% of the samples collected at this site, a nematicide (cadusafos, carbofuran, or ethoprophos) was detected (0.06,6.2 ,g/L). According to this study, most of the insecticide-nematicides analyzed pose a risk for acute or chronic toxicity to aquatic organisms based on the exposure levels and toxicity values from the literature. Ametryn, imazalil, and thiabendazole also exceeded the calculated chronic risk ratio. The most frequently detected compounds in sediments were thiabendazole, chlorpyrifos, imazalil, and propiconazole. The occurrence was higher in the packing plants and streams. Pesticides in waters and sediments of Tortuguero conservation area could pose a threat to this wetland and an additional stress to the endangered species that inhabit this area. More information is needed regarding the distribution and stability of pesticides in the lagoon system as well as of the effects of mixtures of low levels of pesticides and their degradation products on representative species of the Tortuguero ecosystem. Meanwhile, all measures to reduce the emissions of pesticides from the banana plantations and the packing plants should be taken. [source] Olfactory Communication and Neighbor Recognition in Giant Kangaroo RatsETHOLOGY, Issue 2 2001Heather Gardner Murdock We hypothesized that olfactory communication facilitates neighbor recognition in the giant kangaroo rat, Dipodomys ingens, and is therefore influential in coordinating social interactions in this solitary, desert rodent. We tested whether (i) D. ingens can discriminate between odors of same- and opposite-sex conspecifics; and (ii) the kangaroo rats exhibit scent preferences based on familiarity. In habituation-discrimination tests, we found that both genders distinguish differences between the scent of individuals of the same- and opposite-sex. In olfactory preference tests, both males and females spent significantly more time investigating the scent of their familiar cagemate than the scent of an unfamiliar conspecific. Giant kangaroo rats may be able to recognize familiar neighbors from olfactory cues, thus supporting a hypothesis of neighbor recognition. Neighbor recognition may be an important mechanism of social interactions in this endangered species. [source] ORIGINAL ARTICLE: Potential for anthropogenic disturbances to influence evolutionary change in the life history of a threatened salmonidEVOLUTIONARY APPLICATIONS (ELECTRONIC), Issue 2 2008John G. Williams Abstract Although evolutionary change within most species is thought to occur slowly, recent studies have identified cases where evolutionary change has apparently occurred over a few generations. Anthropogenically altered environments appear particularly open to rapid evolutionary change over comparatively short time scales. Here, we consider a Pacific salmon population that may have experienced life-history evolution, in response to habitat alteration, within a few generations. Historically, juvenile fall Chinook salmon (Oncorhynchus tshawytscha) from the Snake River migrated as subyearlings to the ocean. With changed riverine conditions that resulted from hydropower dam construction, some juveniles now migrate as yearlings, but more interestingly, the yearling migration tactic has made a large contribution to adult returns over the last decade. Optimal life-history models suggest that yearling juvenile migrants currently have a higher fitness than subyearling migrants. Although phenotypic plasticity likely accounts for some of the change in migration tactics, we suggest that evolution also plays a significant role. Evolutionary change prompted by anthropogenic alterations to the environment has general implications for the recovery of endangered species. The case study we present herein illustrates the importance of integrating evolutionary considerations into conservation planning for species at risk. [source] Factors affecting habitat selection by a small spawning charr population, bull trout, Salvelinus confluentus: implications for recovery of an endangered speciesFISHERIES MANAGEMENT & ECOLOGY, Issue 1 2004R. C. Wissmar Abstract Bull trout, Salvelinus confluentus (Suckley), populations are declining in many streams of North America and are listed under the Endangered Species Act in the United States. Many small populations are isolated in fragmented habitats where spawning conditions and success are not well understood. Factors affecting habitats selected for redds by spawning bull trout and redd habitat characteristics within Gold Creek, a headwater stream in the Yakima River within the Columbia River basin, Washington State, USA, were evaluated. Most spawning (>80% of the redds) occurred in upstream habitats after dewatering of downstream channels isolated fish. Habitats were selected or avoided in proportions different to their availability. For example, most bull trout selected pools and glides and avoided riffles despite the latter being more readily available. Although preferences suggest influences of prolonged fish entrapment, site fidelity could be important. A habitat with redds commonly contained abundant cover, gravel substratum and higher stream flows. The major factors influencing habitat selection by spawning fish and their persistence in streams of the Yakima and Columbia River regions include entrapment of fish by dewatering of channels and geographical isolation by dams. The goal of the US Government's recovery plan is ,to ensure the long-term persistence of self-sustaining bull trout populations'. Recovery plans linked to provisions for protecting and conserving bull trout populations and their habitats were recommended. Landscape approaches are needed that provide networks of refuge habitats and greater connectivity between populations. Concurrent recovery efforts are encouraged to focus on protecting small populations and minimizing dangers of hybridization. [source] Finnish lake fisheries and conservation of biodiversity: coexistence or conflict?FISHERIES MANAGEMENT & ECOLOGY, Issue 1-2 2000P. Salmi The conservation of biodiversity in aquatic habitats has become an increasingly important challenge in the management of water resources. In addition to the complexity of the lake fishery and the management structure, the popularity of gill net fishing, in particular, has brought problems when re-establishing populations of Arctic charr, Salvelinus alpinus (L.), collecting genetically sustainable numbers of spawners of the land-locked salmon, Salmo salar m. sebago (Girard), and increasing the population of the Saimaa ringed seal, Phoca hispida saimensis (Nordq.) to a sustainable level in the Vuoksi watercourse, south-east Finland. The attitudes towards protection among the users and other interested parties vary. In order to enhance the coexistence of the lake fishery and endangered species over large water areas, improved institutional linkages are needed among the local, regional and governmental levels of the fragmented decision-making regime. Environmental interests should also be integrated into the communication structure. [source] Population size, weight distribution and food in a persistent population of the rare medicinal leech, Hirudo medicinalisFRESHWATER BIOLOGY, Issue 8 2008J. M. ELLIOTT Summary 1. It is important for species recovery and conservation management projects to know the minimum viable population size for rare and endangered species, such as the medicinal leech, Hirudo medicinalis. Therefore, using a catch-removal method, this study estimated every two years (1986, 1988, 1990, 1992) the total number of medicinal leeches in a tarn in the English Lake District, and the number of mature adults in the population. 2. Four samples were taken each year in June and July, when water temperatures exceeded 20 °C. Population size was estimated both by maximum likelihood and regression methods. All leeches were weighed alive and size groups were separated by polymodal frequency analysis. A small sample of the blood meal in each leech gut was taken before the leeches were returned to the tarn, and was used to estimate the proportion of mammalian and non-mammalian blood in the meals. 3. Both methods of estimation produced similar values, increasing confidence in the population estimates. Values for the total population in June and July varied among years from 248 to 288, the maximum value being only 16% higher than the minimum. Values for the number of mature leeches varied from 48 to 58 (19,20% of the total population), and this was an estimate of the effective population size. 4. There were four size groups. The largest mature leeches (live weight >5 g) in group IV formed only 1% of the population, and the smallest (0.02,0.5 g) in group I 14,17%. Most leeches were in two overlapping groups of immature (64,67% of population) and mature (18%) leeches with size ranges of 0.4,3.4 g and 2.5,5 g respectively. The percentage of leeches in each size group was very consistent among years. Blood meals were found in 38,44% of the leeches in group I, 45,50% in group II, 70,75% in group III, and 100% in group IV, but mammalian blood was present only in larger mature leeches (>3.5 g). 5. Medicinal leeches were first detected in the tarn in 1980 and are still present in 2007, so the population has persisted for at least 27 years. Compared with minimum viable population sizes for other species, including many endangered species, values for this medicinal leech population are extremely low, but may be typical of some rare freshwater invertebrates in isolated habitats. [source] Habitat shifts of endangered species under altered climate conditions: importance of biotic interactionsGLOBAL CHANGE BIOLOGY, Issue 11 2008KRISTINE L. PRESTON Abstract Predicting changes in potential habitat for endangered species as a result of global warming requires considering more than future climate conditions; it is also necessary to evaluate biotic associations. Most distribution models predicting species responses to climate change include climate variables and occasionally topographic and edaphic parameters, rarely are biotic interactions included. Here, we incorporate biotic interactions into niche models to predict suitable habitat for species under altered climates. We constructed and evaluated niche models for an endangered butterfly and a threatened bird species, both are habitat specialists restricted to semiarid shrublands of southern California. To incorporate their dependency on shrubs, we first developed climate-based niche models for shrubland vegetation and individual shrub species. We also developed models for the butterfly's larval host plants. Outputs from these models were included in the environmental variable dataset used to create butterfly and bird niche models. For both animal species, abiotic,biotic models outperformed the climate-only model, with climate-only models over-predicting suitable habitat under current climate conditions. We used the climate-only and abiotic,biotic models to calculate amounts of suitable habitat under altered climates and to evaluate species' sensitivities to climate change. We varied temperature (+0.6, +1.7, and +2.8 °C) and precipitation (50%, 90%, 100%, 110%, and 150%) relative to current climate averages and within ranges predicted by global climate change models. Suitable habitat for each species was reduced at all levels of temperature increase. Both species were sensitive to precipitation changes, particularly increases. Under altered climates, including biotic variables reduced habitat by 68,100% relative to the climate-only model. To design reserve systems conserving sensitive species under global warming, it is important to consider biotic interactions, particularly for habitat specialists and species with strong dependencies on other species. [source] Applying climatically associated species pools to the modelling of compositional change in tropical montane forestsGLOBAL ECOLOGY, Issue 2 2008Duncan J. Golicher ABSTRACT Aim, Predictive species distribution modelling is a useful tool for extracting the maximum amount of information from biological collections and floristic inventories. However, in many tropical regions records are only available from a small number of sites. This can limit the application of predictive modelling, particularly in the case of rare and endangered species. We aim to address this problem by developing a methodology for defining and mapping species pools associated with climatic variables in order to investigate potential species turnover and regional species loss under climate change scenarios combined with anthropogenic disturbance. Location, The study covered an area of 6800 km2 in the highlands of Chiapas, southern Mexico. Methods, We derived climatically associated species pools from floristic inventory data using multivariate analysis combined with spatially explicit discriminant analysis. We then produced predictive maps of the distribution of tree species pools using data derived from 451 inventory plots. After validating the predictive power of potential distributions against an independent historical data set consisting of 3105 botanical collections, we investigated potential changes in the distribution of tree species resulting from forest disturbance and climate change. Results, Two species pools, associated with moist and cool climatic conditions, were identified as being particularly threatened by both climate change and ongoing anthropogenic disturbance. A change in climate consistent with low-emission scenarios of general circulation models was shown to be sufficient to cause major changes in equilibrium forest composition within 50 years. The same species pools were also found to be suffering the fastest current rates of deforestation and internal forest disturbance. Disturbance and deforestation, in combination with climate change, threaten the regional distributions of five tree species listed as endangered by the IUCN. These include the endemic species Magnolia sharpii Miranda and Wimmeria montana Lundell. Eleven vulnerable species and 34 species requiring late successional conditions for their regeneration could also be threatened. Main conclusions, Climatically associated species pools can be derived from floristic inventory data available for tropical regions using methods based on multivariate analysis even when data limitations prevent effective application of individual species modelling. Potential consequences of climate change and anthropogenic disturbance on the species diversity of montane tropical forests in our study region are clearly demonstrated by the method. [source] Nest-site selection by Great Bustards Otis tarda suggests a trade-off between concealment and visibilityIBIS, Issue 1 2010MARINA MAGAÑA Great Bustards Otis tarda have expanded their habitat range from historical occupancy of natural steppes to arable farmland, where the species initially benefited from favourable feeding conditions. More recently, the species has suffered severe declines due partly to agricultural intensification. Nest losses and juvenile mortality are amongst the factors most seriously affecting survival probabilities of many populations of this endangered species, suggesting that management of nesting habitats would bring conservation benefits. We studied nest-site selection in a Great Bustard population of central Spain by radiotracking 42 females for periods of between 1 and 4 years. Females selected nest-sites in fallows or cereal fields, in areas of low patch-type diversity, far from human infrastructure, and with good horizontal visibility. These results suggest that females look for shelter, but also need to have good visibility while incubating, and they support the hypothesis that nest selection is a trade-off between concealment and visibility. We interpret both preferences as adaptations to reduce predation pressure, one of the main causes of nest failure in this species. Nests were placed on slopes significantly orientated to the southeast, which suggests that females also seek sites protected from the cold north-westerly winds that are prevalent in the study area. To reduce nest destruction, harvesting should be delayed as long as possible and habitat conservation measures should not be restricted to lek sites but also include nesting areas, which are frequently located far from leks. [source] Biology of a critically endangered species, the Toki (Japanese Crested Ibis) Nipponia nipponIBIS, Issue 1 2000JOHN C. WINGFIELD First page of article [source] Are Australasian academic physicians an endangered species?INTERNAL MEDICINE JOURNAL, Issue 11 2007A. Wilson Abstract It has been stated that academic medicine is in a worldwide crisis. Is this decline in hospital academic practice a predictable consequence of modern clinical practice with its emphasis on community and outpatient-based services as well as a corporate health-care ethos or does it relate to innate problems in the training process and career structure for academic clinicians? A better understanding of the barriers to involvement in academic practice, including the effect of gender, the role and effect of overseas training, expectation of further research degrees and issues pertaining to the Australian academic workplace will facilitate recruitment and retention of the next generation of academic clinicians. Physician-scientists remain highly relevant as medical practice and education evolves in the 21st century. Hospital-based academics carry out a critical role in the ongoing mentoring of trainees and junior colleagues, whose training is still largely hospital based in most specialty programmes. Academic clinicians are uniquely placed to translate the rapid advances in medical biology into the clinical sphere, by guiding and carrying out translational research as well as leading clinical studies. Academic physicians also play key leadership in relations with government and industry, in professional groups and medical colleges. Thus, there is a strong case to assess the problems facing recruitment and retention of physician-scientists in academic practice and to develop workable solutions. [source] Patterns of mortality for each life-history stage in a population of the endangered New Zealand stitchbirdJOURNAL OF ANIMAL ECOLOGY, Issue 4 2009Matthew Low Summary 1Using data from 396 breeding attempts over an 8-year period, we investigated age- and stage-specific survival rates and their modifying factors in a closed island population of the New Zealand stitchbird (or hihi, Notiomystis cincta Du Bus). 2Survival probability generally increased over time; however, at each life-history transition, survival in the new stage started lower than at the end of the previous stage, creating a ,saw-tooth' function of age-related survival. 3The probability of an egg hatching was low (0·73 ± 0·01): most likely a consequence of genetic bottlenecks previously endured by this population. There was strong support for a positive relationship between hatching rate and the subsequent survival of the female parent, and hatching success declining for females > 4 years old. 4Nestling survival probability increased as a function of brood size and days since hatching, and decreased relative to daily maximum ambient temperature and hatching date. Support for models including ambient temperature was greater than for other covariates, with the majority of this temperature-mediated survival effect being restricted to the early nestling stage. 5Fledglings had low survival rates in the first two weeks after leaving the nest, with post-fledging survival related to the fledgling's mass. Two months after fledging, juvenile survival probability plateaued and remained relatively constant for the following autumn, winter and spring/summer breeding season. There was no effect of sex or season on adult survival probability. However, there was strong support for age-specific variation in adult survival, with survival likelihood increasing during the first four years before showing evidence of a senescence decline. 6Within-stage survival increases were likely related to stage-specific selection pressures initially weeding out individuals of poorer phenotypes for the environment specific to each life-history stage. Such a mechanism explains the initial high mortality at life-history transitions; a well-adapted phenotype for one stage may not necessarily be so well adapted for subsequent stages. These patterns are not only valuable for examining life-history theory, but also for understanding the regulation of vital rates in an endangered species and providing a basis from which better population management models and harvesting regimes can be derived. [source] | |||||||||||||||||||||||||||||||||||||||||||