Biodiversity Conservation (biodiversity + conservation)

Distribution by Scientific Domains
Distribution within Life Sciences


Selected Abstracts


CREATION OF MARINE RESERVES AND INCENTIVES FOR BIODIVERSITY CONSERVATION

NATURAL RESOURCE MODELING, Issue 2 2010
QUACH THI KHANH NGOC
Abstract Despite a number of benefits, marine reserves provide neither incentives for fishermen to protect biodiversity nor compensation for financial loss due to the designation of the reserves. To obtain fishermen's support for marine reserves, some politicians have suggested that managers of new marine reserves should consider subsidizing or compensating those fishermen affected by the new operations. The objective of this paper is to apply principal,agent theory, which is still infrequently applied to fisheries, to define the optimal reserve area, fishing effort, and transfer payments in the context of symmetric and asymmetric information between managers and fishermen. The expected optimal reserve size under asymmetric information is smaller than that under symmetric information. Fishing efforts encouraged with a transfer payment are always less compared to those without payment. This reflects the fact that as the manager induces the fishermen to participate in the conservation program, the fishermen will take into account their effects on fish stock by decreasing their effort. Examples are also supplied to demonstrate these concepts. [source]


Biodiversity Conservation in Agricultural Landscapes: Challenges and Opportunities of Coffee Agroforests in the Western Ghats, India

CONSERVATION BIOLOGY, Issue 2 2010
CLAUDE A. GARCIA
agroforestería de café; Ghats Occidentales; medios de vida; mosaicos paisajísticos; proyectos integrados de conservación y desarrollo Abstract:,The new approaches advocated by the conservation community to integrate conservation and livelihood development now explicitly address landscape mosaics composed of agricultural and forested land rather than only protected areas and largely intact forests. We refer specifically to a call by Harvey et al. (2008) to develop a new approach based on six strategies to integrate biodiversity conservation with sustainable livelihoods in Mesoamerican landscape mosaics. We examined the applicability of this proposal to the coffee agroforests of the Western Ghats, India. Of the six strategies, only one directly addresses livelihood conditions. Their approach has a clear emphasis on conservation and, as currently formulated risks repeating the failures of past integrated conservation and development projects. It fails to place the aspirations of farmers at the core of the agenda. Thus, although we acknowledge and share the broad vision and many of the ideas proposed by this approach, we urge more balanced priority setting by emphasizing people as much as biodiversity through a careful consideration of local livelihood needs and aspirations. Resumen:,Los nuevos enfoques recomendados por la comunidad de conservación para integrar la conservación y el desarrollo ahora abordan explícitamente los mosaicos paisajísticos compuestos de tierras agrícolas y forestales en lugar de solo áreas protegidas y bosques casi intactos. Basado en seis estrategias para integrar la conservacion de la biodiversidad con modos de vida sustentables en los mosaicos paisajisticos de Mesoamerica. Nos referimos específicamente a la llamada de Harvey et al. (2008) para desarrollar un enfoque nuevo basado en seis estrategias para congraciar la conservación de la biodiversidad con modos de vida sustentables en los mosaicos paisajísticos de Mesoamérica. Examinamos la aplicabilidad de esta propuesta en los agrobosques de café de los Ghats occidentales en la India. Solo una de las seis estrategias mencionadas aborda directamente las condiciones de vida. La propuesta tiene un claro énfasis en la conservación y, tal como está formulada actualmente, falla en colocar las aspiraciones de los campesinos en el centro de la agenda. Corre pues el riesgo de repetir los fracasos de pasados proyectos integrados de conservación y desarrollo. Por lo tanto, aunque reconocemos y compartimos la amplia visión y muchas de las ideas de esta llamada, insistimos en una definición de prioridades balanceada que enfatice a la gente tanto como a la biodiversidad mediante una consideración cuidadosa de las necesidades y aspiraciones de los habitantes locales. [source]


The Multifaceted Nature of Biodiversity Conservation: Reply to Leroux and Schmiegelow

CONSERVATION BIOLOGY, Issue 1 2007
JOHN F. LAMOREUX
No abstract is available for this article. [source]


Salvage Logging, Ecosystem Processes, and Biodiversity Conservation

CONSERVATION BIOLOGY, Issue 4 2006
D.B. LINDENMAYER
conservación de la biodiversidad; gestión forestal; procesos ecosistémicos Abstract:,We summarize the documented and potential impacts of salvage logging,a form of logging that removes trees and other biological material from sites after natural disturbance. Such operations may reduce or eliminate biological legacies, modify rare postdisturbance habitats, influence populations, alter community composition, impair natural vegetation recovery, facilitate the colonization of invasive species, alter soil properties and nutrient levels, increase erosion, modify hydrological regimes and aquatic ecosystems, and alter patterns of landscape heterogeneity. These impacts can be assigned to three broad and interrelated effects: (1) altered stand structural complexity; (2) altered ecosystem processes and functions; and (3) altered populations of species and community composition. Some impacts may be different from or additional to the effects of traditional logging that is not preceded by a large natural disturbance because the conditions before, during, and after salvage logging may differ from those that characterize traditional timber harvesting. The potential impacts of salvage logging often have been overlooked, partly because the processes of ecosystem recovery after natural disturbance are still poorly understood and partly because potential cumulative effects of natural and human disturbance have not been well documented. Ecologically informed policies regarding salvage logging are needed prior to major natural disturbances so that when they occur ad hoc and crisis-mode decision making can be avoided. These policies should lead to salvage-exemption zones and limits on the amounts of disturbance-derived biological legacies (e.g., burned trees, logs) that are removed where salvage logging takes place. Finally, we believe new terminology is needed. The word salvage implies that something is being saved or recovered, whereas from an ecological perspective this is rarely the case. Resumen:,Resumimos los impactos documentados y potenciales de la cosecha de salvamento , una forma de cosecha de madera que remueve árboles y otros materiales biológicos después de una perturbación natural. Tales operaciones pueden reducir o eliminar legados biológicos, modificar hábitats post perturbación, influir en poblaciones, alterar la composición de comunidades, impedir la recuperación de la vegetación natural, facilitar la colonización de especies invasoras, alterar las propiedades del suelo y de niveles de nutrientes, incrementar la erosión, modificar regímenes hidrológicos y ecosistemas acuáticos, y alterar patrones de heterogeneidad del paisaje. Estos impactos se pueden asignar a tres efectos amplios e interrelacionados: (1) alteración de la complejidad estructural del bosque; (2) alteración de procesos y funciones ecológicas; y (3) alteración de poblaciones de especies y de la composición de la comunidad. Algunos impactos pueden ser diferentes a o adicionales a los efectos de la cosecha de madera tradicional que no es precedida de una perturbación natural severa porque las condiciones antes, durante y después de la cosecha de salvamento pueden diferir de las que caracterizan a la cosecha de madera tradicional. Los impactos potenciales de la cosecha de salvamento a menudo han sido pasados por alto, en parte porque los procesos de recuperación del ecosistema después de una perturbación natural son poco conocidos y en parte porque los efectos acumulativos potenciales de perturbaciones naturales y humanas no han sido bien documentados. Se requieren políticas ecológicamente informadas para la cosecha de salvamento para que cuando ocurran las perturbaciones naturales se evite la toma de decisiones en situaciones de crisis. Estas políticas deberán establecer zonas exentas de salvamento y límites a las cantidades de legados biológicos derivados de la perturbación (e. g., árboles quemados, troncos) que son removidos donde se lleva a cabo la cosecha de salvamento. Finalmente, creemos que se requiere una nueva terminología. La palabra salvamento implica que algo esta siendo salvado o recuperado, y este raramente es el caso desde una perspectiva ecológica. [source]


The Devil in the Detail of Biodiversity Conservation

CONSERVATION BIOLOGY, Issue 1 2003
Thomas O. McShane
No abstract is available for this article. [source]


Biogeographic Crossroads as Priority Areas for Biodiversity Conservation

CONSERVATION BIOLOGY, Issue 6 2002
Sacha Spector
I suggest that targeting the regions where biogeographic assemblages intersect,"biogeographic crossroads",is a strategy that may achieve significant conservation economy by focusing on areas that satisfy many conservation criteria. I used a combination of data on Scarabaeine beetles in Bolivia and on other taxa and locations from the literature to consider the short- and long-term benefits of conserving these biogeographic crossroads. Biogeographic crossroads are areas of high species richness and beta diversity, often across many taxonomic groups. They are also regions where representativeness can be achieved with relative efficiency. Recent evidence that ecotones may be loci of evolution suggests that evolutionary processes such as speciation and coevolution may be conserved at biogeographic crossroads. Biogeographic crossroads appear to be areas of high conservation priority and opportunity in both the short and long term and require increased attention in the process of setting conservation priorities. Resumen: Las amenazas a la biodiversidad rebasan los recursos de la comunidad conservacionista y requieren de una cuidadosa priorización de las acciones de conservación. Sugiero que enfocar en las regiones donde intersectan ensambles biogeográficos,"intersecciones biogeográficas", es una estrategia que puede lograr una economía significativa de los esfuerzos de conservación al atender áreas que satisfacen muchos criterios de conservación. Utilicé una combinación de datos de escarabajos Scarabaeine de Bolivia y de otros taxones y localidades de la literatura para considerar los beneficios a corto y largo plazo de conservar estas intersecciones biogeográficas. Las intersecciones biogeográficas son áreas de alta riqueza de especies y de diversidad beta, y probablemente éste sea el caso de muchos grupos taxonómicos. También son regiones en las que se puede alcanzar representatividad con relativa eficiencia. Evidencia reciente de que los ecotonos pueden ser sitios de evolución sugiere que los procesos evolutivos tales como la especiación y coevolución pueden ser conservados en intersecciones biogeográficas. Las intersecciones biogeográficas parecen ser áreas de alta prioridad y oportunidad de conservación tanto a corto como a largo plazo y requieren mayor atención en el proceso de definición de prioridades de conservación. [source]


Economically Destructive Fires and Biodiversity Conservation: an Australian Perspective

CONSERVATION BIOLOGY, Issue 6 2001
A. Malcolm Gill
No abstract is available for this article. [source]


Heavy Extinctions of Forest Avifauna in Singapore: Lessons for Biodiversity Conservation in Southeast Asia

CONSERVATION BIOLOGY, Issue 6 2000
Marjorie Castelletta
In Southeast Asia, Singapore, a newly developing country, has had 95% of its native lowland rainforest cleared. Most of the rainforest was lost in the mid- to late-nineteenth century. We compared avifauna checklists from 1923, 1949, and 1998 to determine the extent of extinctions between 1923 and 1998 in Singapore. Of 203 diurnal bird species, 65 were extirpated in Singapore in the past 75 years. Four of these species were nonforest- dependent species, whereas 61 (94%) were forest bird species dependent on the primary or old secondary forest to survive. Twenty-six forest bird species became extinct between 1923 and 1949, whereas 35 forest species disappeared after 1949. We compared the body lengths, feeding guilds, and vertical feeding zones between extinct and extant forest bird species to determine whether extinction patterns were dependent on these characteristics. Larger forest bird species went extinct between 1923 and 1949. Body sizes, however, did not affect the loss of forest bird species between 1949 and 1998. We observed high losses of insectivorous birds; the insectivore-carnivore and insectivore-granivore guilds lost> 80% of the species present in 1923. The highest losses were among birds that fed in the canopy. None of the forest bird species are currently common (>100 individuals/species) within Singapore. Our study shows that more than half the forest avifauna became locally extinct after extensive deforestation. Based on this fact, the countries within Southeast Asia should reconsider their heavy deforestation practices. Resumen: Las consecuencias de la tala rápida del bosque lluvioso sobre la avifauna nativa son poco conocidas. En Asia sudoriental, Singapur, un país en desarrollo, un 95% de su bosque nativo de tierras bajas ha sido talado. La mayoríia del bosque se perdió entre mediados y finales del siglo diecinueve. En este trabajo comparamos las listas de avifauna de 1923, 1949 y 1998 para determinar la extensión de las extinciones en Singapur entre 1923 y 1998. Sesenta y cinco de las 203 especies diurnas de aves fueron extirpadas de Singapur en los últimos 75 años. Cuatro de estas especies fueron especies no dependientes del bosque, mientras que 61 (94%) fueron especies de aves del bosque (especies que dependen del bosque primario o secundario viejo para sobrevivir). Veintiséis de las especies de aves del bosque se extinguieron entre 1923 y 1949, mientras que 35 especies del bosque desaparecieron después de 1949. Comparamos las longitudes del cuerpo, los gremios de alimentación y las zonas de alimentación vertical entre especies de aves de bosque extintas y existentes para determinar si los patrones de extinción fueron dependientes de estas características. Las especies de aves grandes del bosque se extinguieron entre 1923 y 1949. Sin embargo, el tamaño del cuerpo no afectó la pérdida de especies del bosque entre 1949 y 1998. Observamos altas pérdidas de aves insectívoras; los gremios de insectívoros-carnívoros e insectívoros-granívoros perdieron> 80% de las especies que estaban presentes en 1923. Los números más altos de pérdidas fueron de aves que se alimentan en el dosel. Ninguna de las especies de aves del bosque es común en la actualidad (>100 individuos/especie) dentro de Singapur. Nuestro estudio muestra que más de la mitad de la avifauna del bosque se ha extinguido localmente después de una deforestación extensiva. Con base en este hecho, los países dentro de Asia Sudoriental deberían reconsiderar sus prácticas de intensa deforestación. [source]


Regional Planning in Queensland's Rangelands: Challenges and Prospects for Biodiversity Conservation

GEOGRAPHICAL RESEARCH, Issue 1 2007
CLIVE A. MCALPINE
Abstract In Australia, the Commonwealth and State governments are increasingly devolving natural resource management (NRM) responsibilities to regional bodies. This move has led to the development of regional NRM plans. Native vegetation and biodiversity conservation, along with soil, pasture and water resources, are key components of the regional NRM plans in Queensland's extensive rangelands. This paper outlines and applies a set of criteria for evaluating the native vegetation and biodiversity content of accredited regional NRM plans for Queensland's rangelands. The evaluation showed considerable variation in the comprehensiveness of the information and knowledge base and management action targets among plans, including the poor articulation of impacts of excessive grazing pressure on biodiversity. The NRM plans lacked effective integration of natural resource, native vegetation and biodiversity conservation targets and actions. Several regions had too many biodiversity targets, many of which were poorly integrated. This is symptomatic of a limited understanding of rangelands as ecological systems and the lack of an integrated planning framework. We conclude regional NRM planning is not a ,silver bullet' for biodiversity conservation in the rangelands, but rather, it is the beginning of a long road to address complex, multi-scale problems at a regional level. [source]


Capitalism and Conservation: The Production and Reproduction of Biodiversity Conservation

ANTIPODE, Issue 3 2010
Dan Brockington
First page of article [source]


A Spectacular Eco-Tour around the Historic Bloc: Theorising the Convergence of Biodiversity Conservation and Capitalist Expansion

ANTIPODE, Issue 3 2010
Jim Igoe
Abstract:, The simultaneous proliferation of protected areas for biodiversity conservation and neoliberal market expansion has sparked a growing body of work, which suggests that these are mutually reinforcing processes that reflect alliances between conservationist and capitalist agendas. Because this alliance is so counter intuitive to the ways in which biodiversity conservation is popularly understood, theoretical perspectives concerning these relationships have been slow in emerging. Drawing from Gramsci's ideas of hegemony and historic bloc, we propose a theoretical framework systematically to inform understandings and investigations of these transformations. We suggest that they are driven by the convergence of networks of interests, which work to resolve the apparent contradictions between demands for continued economic growth and growing concerns about what it portends for the future of our planet. These in turn rely on spectacular presentations of conservation interventions, conservation success stories, and their putative linkages to ecosystems and the global economy. [source]


The Devil is in the (Bio)diversity: Private Sector "Engagement" and the Restructuring of Biodiversity Conservation

ANTIPODE, Issue 3 2010
Kenneth Iain MacDonald
Abstract:, Intensified relations between biodiversity conservation organizations and private-sector actors are analyzed through a historical perspective that positions biodiversity conservation as an organized political project. Within this view the organizational dimensions of conservation exist as coordinated agreement and action among a variety of actors that take shape within radically asymmetrical power relations. This paper traces the privileged position of "business" in aligning concepts of sustainable development and ecological modernization within the emerging institutional context of the Convention on Biological Diversity and the Global Environment Facility in ways that help to secure continued access to "nature as capital", and create the institutional conditions to shape the work of conservation organizations. The contemporary emergence of business as a major actor in shaping contemporary biodiversity conservation is explained in part by the organizational characteristics of modernist conservation that subordinates it to larger societal and political projects such as neoliberal capitalism. [source]


Disconnected Nature: The Scaling Up of African Wildlife Foundation and its Impacts on Biodiversity Conservation and Local Livelihoods

ANTIPODE, Issue 3 2010
Hassanali T. Sachedina
Abstract:, Much has been written about the resource crisis facing the conservation movement if it is to scale up successfully to face what are perceived as global threats such as biodiversity loss, poverty and climate change. But what happens to conservation organizations when they successfully scale up, and what are the impacts on biodiversity and local people? This paper attempts to chart the successful scaling up of an international conservation NGO, the African Wildlife Foundation, and examines the implications of this on its performance in community-based wildlife conservation in Tanzania. [source]


Corridor Ecology: The Science and Practice of Linking Landscapes for Biodiversity Conservation

AUSTRAL ECOLOGY, Issue 3 2007
GREG BAXTER
No abstract is available for this article. [source]


Biodiversity conservation in Mediterranean and Black Sea lagoons: a trait-oriented approach to benthic invertebrate guilds

AQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue S1 2008
A. Basset
Abstract 1. The extent to which conservation of biodiversity enforces the protection of ecosystem functioning, goods and services is a key issue in conservation ecology. 2. In order to address this conservation issue, this work focused on community organization, linking community structure, as described both in taxonomic and functional terms, to community functioning and ecosystem processes. 3. Body size is an individual functional trait that is deterministically related to components of ecosystem functioning such as population dynamics and energy flow, and which determines components of community structure. Since body size is an individual trait that reflects numerous factors, it is also exposed to trait selection and the niche filtering underlying the community. 4. An analysis of the relevance of body size to community organization in transitional water ecosystems in the eastern Mediterranean and Black Sea regions is presented, based on field research conducted on a sample of 15 transitional water ecosystems. 5. 250 taxa were identified, clumped in five orders of magnitude of body size. All body size patterns showed triangular distributions with an optimal size range of 0.13 mg to 1.0 mg individual body mass. 6. Deterministic components of size structure were emphasized and a hierarchical organization with dominance of large sizes was demonstrated by the slopes of the body size-abundance distributions, consistently larger than the EER threshold (b=,0.75), and by the direct relationship of energy use to body size for most of the body size range. 7. Consistent variations of body size-related descriptors were observed on three main gradients of environmental stress: eutrophication, confinement and metal pollution. 8. The results support the relevance of constraints imposed by individual body size on community organization in transitional water ecosystems and the adequacy of size patterns as an indicator for ecological conservation of these fragile ecosystems. Copyright © 2008 John Wiley & Sons, Ltd. [source]


Biodiversity Conservation in Agricultural Landscapes: Challenges and Opportunities of Coffee Agroforests in the Western Ghats, India

CONSERVATION BIOLOGY, Issue 2 2010
CLAUDE A. GARCIA
agroforestería de café; Ghats Occidentales; medios de vida; mosaicos paisajísticos; proyectos integrados de conservación y desarrollo Abstract:,The new approaches advocated by the conservation community to integrate conservation and livelihood development now explicitly address landscape mosaics composed of agricultural and forested land rather than only protected areas and largely intact forests. We refer specifically to a call by Harvey et al. (2008) to develop a new approach based on six strategies to integrate biodiversity conservation with sustainable livelihoods in Mesoamerican landscape mosaics. We examined the applicability of this proposal to the coffee agroforests of the Western Ghats, India. Of the six strategies, only one directly addresses livelihood conditions. Their approach has a clear emphasis on conservation and, as currently formulated risks repeating the failures of past integrated conservation and development projects. It fails to place the aspirations of farmers at the core of the agenda. Thus, although we acknowledge and share the broad vision and many of the ideas proposed by this approach, we urge more balanced priority setting by emphasizing people as much as biodiversity through a careful consideration of local livelihood needs and aspirations. Resumen:,Los nuevos enfoques recomendados por la comunidad de conservación para integrar la conservación y el desarrollo ahora abordan explícitamente los mosaicos paisajísticos compuestos de tierras agrícolas y forestales en lugar de solo áreas protegidas y bosques casi intactos. Basado en seis estrategias para integrar la conservacion de la biodiversidad con modos de vida sustentables en los mosaicos paisajisticos de Mesoamerica. Nos referimos específicamente a la llamada de Harvey et al. (2008) para desarrollar un enfoque nuevo basado en seis estrategias para congraciar la conservación de la biodiversidad con modos de vida sustentables en los mosaicos paisajísticos de Mesoamérica. Examinamos la aplicabilidad de esta propuesta en los agrobosques de café de los Ghats occidentales en la India. Solo una de las seis estrategias mencionadas aborda directamente las condiciones de vida. La propuesta tiene un claro énfasis en la conservación y, tal como está formulada actualmente, falla en colocar las aspiraciones de los campesinos en el centro de la agenda. Corre pues el riesgo de repetir los fracasos de pasados proyectos integrados de conservación y desarrollo. Por lo tanto, aunque reconocemos y compartimos la amplia visión y muchas de las ideas de esta llamada, insistimos en una definición de prioridades balanceada que enfatice a la gente tanto como a la biodiversidad mediante una consideración cuidadosa de las necesidades y aspiraciones de los habitantes locales. [source]


Quantifying Plant Population Persistence in Human-Dominated Landscapes

CONSERVATION BIOLOGY, Issue 4 2008
DAWN M. LAWSON
Base de Datos de la Diversidad Natural de California; conservación de plantas; crecimiento de la población; especies en peligro; paisajes urbanos Abstract:,We assessed population performance of rare plants across a gradient from rural to urban landscapes and evaluated 2 hypotheses central to strategic conservation planning: (1) population performance declines with increasing human dominance and (2) small populations perform poorly relative to larger ones. Assessing these hypotheses is critical to strategic conservation planning. The current conservation paradigm adheres to the well-established ecology theory that small isolated populations, particularly those in human-dominated landscapes, are the least likely to succeed over the long term. Consequently, conservation planning has strongly favored large, remote targets for protection. This shift in conservation toward ecosystem-based programs and protection of populations within large, remote systems has been at the expense of protection of the rarest of the rare species, the dominant paradigm for conservation driven by the endangered species act. Yet, avoiding conservation of small populations appears to be based more on theoretical understanding and expert opinion than empiricism. We used Natural Heritage data from California in an assessment of population performance of rare plants across a landscape with an urban-rural gradient. Population performance did not decrease in urban settings or for populations that were initially small. Our results are consistent with a pattern of few species extinctions within these landscapes over the past several decades. We conclude that these populations within compromised landscapes can contribute to overall biodiversity conservation. We further argue that conservation planning for biodiversity preservation should allocate relatively more resources to protecting urban-associated plant taxa because they may provide conservation benefit beyond simply protecting isolated populations; they may be useful in building social interest in conservation. Resumen:,Evaluamos el funcionamiento de la población de plantas raras a lo largo de un gradiente de paisajes rurales a urbanos y evaluamos 2 hipótesis centrales para la planificación estratégica de la conservación: (1) declinaciones en el funcionamiento poblacional con el incremento de la dominancia humana y (2) las poblaciones pequeñas funcionan pobremente en relación con las grandes. La evaluación de estas hipótesis es crítica para la planificación estratégica de la conservación. El paradigma actual de la conservación se adhiere a la teoría ecológica bien establecida que propone que las poblaciones pequeñas aisladas, particularmente en paisajes dominados por humanos, tienen menor probabilidad de sobrevivir a largo plazo. Consecuentemente, la planificación de la conservación ha favorecido objetivos grandes y remotos. Este cambio hacia programas de conservación basados en ecosistemas y la protección de poblaciones en sistemas extensos y remotos ha sido a costa de la protección de las especies más raras entre las raras, el paradigma dominante en la conservación conducida por el acta de especies en peligro. No obstante, la evasión de la conservación de poblaciones pequeñas parece estar basada más en entendimiento teórico y en la opinión de expertos que en el empirismo. Utilizamos datos del Patrimonio Natural de California en una evaluación del funcionamiento de plantas raras en un paisaje con un gradiente urbano a rural. El funcionamiento de la población no decreció en sitios urbanos o en poblaciones que eran pequeñas inicialmente. Nuestros resultados son consistentes con un patrón de extinción de especies en estos paisajes en las últimas décadas. Concluimos que estas poblaciones en paisajes comprometidos pueden contribuir a la conservación de la biodiversidad en general. También argumentamos que la planificación de la conservación para la preservación de la biodiversidad debería asignar más recursos para la protección de taxa de plantas asociadas a ambientes urbanos porque pueden proporcionar beneficios de conservación más allá de simplemente proteger poblaciones aisladas; pueden ser útiles para construir el interés social por la conservación. [source]


Incorporation of Recreational Fishing Effort into Design of Marine Protected Areas

CONSERVATION BIOLOGY, Issue 5 2006
TIM P. LYNCH
consulta pública; modelos de reservas marinas; pesca con caña; suposiciones de poza dinámica Abstract:,Theoretical models of marine protected areas (MPAs) that explore benefits to fisheries or biodiversity conservation often assume a dynamic pool of fishing effort. For instance, effort is homogenously distributed over areas from which subsets of reserves are chosen. I tested this and other model assumptions with a case study of the multiple-use Jervis Bay Marine Park. Prior to zoning of the park I conducted 166 surveys of the park's recreational fisheries, plotting the location of 16,009 anglers. I converted these plots into diagrams of fishing effort and analyzed correlates between fishing and habitat and the effect of two reserve designs,the draft and final zoning plans of the park,on the 15 fisheries observed. Fisheries were strongly correlated with particular habitats and had negatively skewed and often bimodal spatial distribution. The second mode of intensely fished habitat could be 6 SD greater than the fishery's mean allocation of effort by area. In the draft-zoning plan, sanctuary zone (no-take) area and potential subduction of fishing effort were similar. In the final plan, which was altered in response to public comment, the area of sanctuary zone increased, and the impact on fishing effort decreased. In only one case was a fishery's most intensely targeted location closed to fishing. Because of the discriminating manner with which fishers target habitats, if simple percentage targets are used for planning, sanctuary location can be adjusted to avoid existing fishing effort. According to modeled outcomes, the implication of this may be diminished reserve effectiveness. To address this, reserve area should be implicitly linked to subducted fishing effort when promoting or modeling MPAs. Resumen:,Los modelos teóricos de áreas marinas protegidas (AMPs) que exploran los beneficios para las pesquerías o la conservación de la biodiversidad a menudo asumen que hay una poza dinámica en el esfuerzo de pesca. Por ejemplo, el esfuerzo es distribuido homogéneamente en áreas en las que se seleccionan subconjuntos de reservas. Probé esta y otras suposiciones del modelo con un estudio de caso del Parque Marino Jarvis Bay. Antes de la zonificación del parque, realicé 166 muestreos de las pesquerías recreativas del parque, dibujando la localización de 16,009 pescadores con caña. Convertí estos dibujos en diagramas de esfuerzo de pesca y analicé las correlaciones entre la pesca, el hábitat y el efecto de dos diseños de reserva,el anteproyecto y los planes finales de zonificación del parque,sobre las 15 pesquerías observadas. Las pesquerías se correlacionaron fuertemente con los hábitats particulares y tenían una distribución espacial sesgada negativamente y a menudo bimodal. El segundo tipo de hábitat pescado intensivamente podría ser 6 DS mayor que la asignación promedio de esfuerzo de pesquería por unidad de área. En el anteproyecto de plan de zonificación, el área santuario (sin pesca) y la subducción potencial del esfuerzo de pesca eran similares. En el plan final, que fue alterado en respuesta a comentarios del público, el área del santuario fue incrementada, y el impacto del esfuerzo de pesca disminuyó. En solo un caso fue cerrado a la pesca la localidad de pesca más intensiva. Debido a la forma discriminada en que los pescadores eligen los hábitats, si se utilizan objetivos porcentuales simples para la planificación, la localización del santuario puede ser ajustada para evitar el esfuerzo de pesca existente. De acuerdo con los resultados del modelo, la implicación puede ser la disminución de la efectividad de la reserva. Para abordar esto, el área de la reserva debiera estar implícitamente relacionada con la reducción del esfuerzo de pesca cuando se promueven o modelan AMPs. [source]


Economic Growth and Biodiversity Loss in an Age of Tradable Permits

CONSERVATION BIOLOGY, Issue 4 2006
JON ROSALES
comercio de emisiones; límite y comercio; proceso ciencia-política; Protocolo de Kyoto Abstract:,Tradable permits are increasingly becoming part of environmental policy and conservation programs. The efficacy of tradable permit schemes in addressing the root cause of environmental decline,economic growth,will not be achieved unless the schemes cap economic activity based on ecological thresholds. Lessons can be learned from the largest tradable permit scheme to date, emissions trading now being implemented with the Kyoto Protocol. The Kyoto Protocol caps neither greenhouse gas emissions at a level that will achieve climate stability nor economic growth. If patterned after the Kyoto Protocol, cap-and-trade schemes for conservation will not ameliorate biodiversity loss either because they will not address economic growth. In response to these failures to cap economic growth, professional organizations concerned about biodiversity conservation should release position statements on economic growth and ecological thresholds. The statements can then be used by policy makers to infuse these positions into the local, national, and international environmental science-policy process when these schemes are being developed. Infusing language into the science-policy process that calls for capping economic activity based on ecological thresholds represents sound conservation science. Most importantly, position statements have a greater potential to ameliorate biodiversity loss if they are created and released than if this information remains within professional organizations because there is the potential for these ideas to be enacted into law and policy. Resumen:,Cada vez más, los permisos comerciables son parte de la política ambiental y de los programas de conservación. La eficacia de los esquemas de permisos comerciables para atender la causa principal de la declinación ambiental,crecimiento económico,será baja a menos que los esquemas limiten la actividad económica con base en umbrales ecológicos. Se pueden aprender lecciones del mayor esquema de permisos comerciables a la fecha, la comercialización de emisiones implementada con el Protocolo de Kyoto. El Protocolo de Kyoto no limita a las emisiones de gases a un nivel que logre la estabilidad climática ni al crecimiento económico. Si se sigue el modelo del Protocolo de Kyoto, los esquemas de límite y comercio tampoco reducirán las pérdidas de biodiversidad porque no considerarán al crecimiento económico. En respuesta a estas fallas para limitar el crecimiento económico, las organizaciones profesionales preocupadas por la conservación de la biodiversidad deberían emitir declaraciones sobre su posición respecto a umbrales ecológicos y de crecimiento económico. Las declaraciones luego pueden ser usadas por políticos para infundir estas posiciones en el proceso ciencia ambiental-política a nivel local, nacional e internacional cuando estos esquemas estén siendo desarrollados. La infusión de lenguaje que demanda la limitación de actividades de crecimiento económico con base en umbrales ecológicos es ciencia de la conservación sólida. Más notablemente, las declaraciones de posición tienen un mayor potencial para reducir las pérdidas de biodiversidad si son creadas y publicadas que si esta información permanece dentro de las organizaciones profesionales porque existe el potencial para que estas ideas se constituyan en leyes y políticas. [source]


Refining Biodiversity Conservation Priorities

CONSERVATION BIOLOGY, Issue 6 2005
GRANT M. HARRIS
Bosque del Atlántico; percepción remota; priorización; SIG; sitios prioritarios para la conservación Abstract:,Although there is widespread agreement about conservation priorities at large scales (i.e., biodiversity hotspots), their boundaries remain too coarse for setting practical conservation goals. Refining hotspot conservation means identifying specific locations (individual habitat patches) of realistic size and scale for managers to protect and politicians to support. Because hotspots have lost most of their original habitat, species endemic to them rely on what remains. The issue now becomes identifying where this habitat is and these species are. We accomplished this by using straightforward remote sensing and GIS techniques, identifying specific locations in Brazil's Atlantic Forest hotspot important for bird conservation. Our method requires a regional map of current forest cover, so we explored six popular products for mapping and quantifying forest: MODIS continuous fields and a MODIS land cover (preclassified products), AVHRR, SPOT VGT, MODIS (satellite images), and a GeoCover Landsat thematic mapper mosaic (jpg). We compared subsets of these forest covers against a forest map based on a Landsat enhanced thematic mapper. The SPOT VGT forest cover predicted forest area and location well, so we combined it with elevation data to refine coarse distribution maps for forest endemic birds. Stacking these species distribution maps enabled identification of the subregion richest in threatened birds,the lowland forests of Rio de Janeiro State. We highlighted eight priority fragments, focusing on one with finer resolved imagery for detailed study. This method allows prioritization of areas for conservation from a region >1 million km2 to forest fragments of tens of square kilometers. To set priorities for biodiversity conservation, coarse biological information is sufficient. Hence, our method is attractive for tropical and biologically rich locations, where species location information is sparse. Resumen:,Aunque hay acuerdo generalizado sobre las prioridades de conservación a escalas mayores (i. e., sitios prioritarios para la conservación de la biodiversidad), los límites son muy gruesos como para definir metas de conservación prácticas. La refinación de la conservación de sitios prioritarios significa la identificación de localidades específicas (parches de hábitat individuales) de tamaño y escala realistas para ser protegidos por gestores y apoyados por políticos. Debido a que los sitios prioritarios han perdido la mayor parte de su hábitat original, las especies endémicas dependen del que permanece. Ahora el asunto es identificar donde están el hábitat y las especies. Logramos lo anterior mediante técnicas directas de percepción remota y de SIG para identificar localidades específicas importantes para la conservación de aves en el sitio prioritario Bosque del Atlántico en Brasil. Nuestro método requiere de un mapa regional de la cobertura forestal actual, así que exploramos seis productos populares para el mapeo y cuantificación de bosques: campos continuos MODIS y una cobertura de suelo MODIS (productos preclasificados), AVHRR, SPOT VGT, MODIS (imágenes de satélite) y un mosaico GeoCover Landsat thematic mapper (jpg). Comparamos subconjuntos de estas coberturas forestales con las de un mapa basado en un Landsat enhanced thematic mapper. La cobertura forestal SPOT VGT predijo bien la superficie y localización del bosque, así que lo combinamos con datos de altitud para refinar los mapas generales de distribución de aves endémicas de bosques. La sobreposición de estos mapas de distribución permitió la identificación de la subregión más rica en aves amenazadas,los bosques en bajíos del Estado de Río de Janeiro. Dimos relevancia a ocho fragmentos prioritarios, con atención en uno con imágenes de resolución fina para estudio en detalle. Este método permite la priorización de áreas para conservación de fragmentos de decenas de kilómetros cuadrados en una región >1 millón km2. La información biológica general es suficiente para definir prioridades de conservación de la biodiversidad. Por lo tanto, nuestro método es atractivo para localidades tropicales y biológicamente ricas, para las que la información sobre la ocalización de las especies es escasa. [source]


A Review of Feral Cat Eradication on Islands

CONSERVATION BIOLOGY, Issue 2 2004
MANUEL NOGALES
efecto de depredación; erradicación; Felis catus; gato asilvestrado; islas Abstract:,Feral cats are directly responsible for a large percentage of global extinctions, particularly on islands. We reviewed feral cat eradication programs with the intent of providing information for future island conservation actions. Most insular cat introductions date from the nineteenth and twentieth centuries, whereas successful eradication programs have been carried out in the last 30 years, most in the last decade. Globally, feral cats have been removed from at least 48 islands: 16 in Baja California (Mexico), 10 in New Zealand, 5 in Australia, 4 in the Pacific Ocean, 4 in Seychelles, 3 in the sub-Antarctic, 3 in Macaronesia (Atlantic Ocean), 2 in Mauritius, and 1 in the Caribbean. The majority of these islands (75%; n= 36) are small (,5 km2). The largest successful eradication campaign took place on Marion Island (290 km2), but cats have been successfully removed from only 10 islands (21%) of ,10 km2. On Cousine Island (Seychelles) cat density reached 243 cats/km2, but on most islands densities did not exceed 79.2 cats/km2 (n= 22; 81%). The most common methods in successful eradication programs were trapping and hunting (often with dogs; 91% from a total of 43 islands). Frequently, these methods were used together. Other methods included poisoning (1080; monofluoracetate in fish baits; n= 13; 31%), secondary poisoning from poisoned rats (n= 4; 10%), and introduction of viral disease (feline panleucopaenia; n= 2; 5%). Impacts from cat predation and, more recently, the benefits of cat eradications have been increasingly documented. These impacts and benefits, combined with the continued success of eradication campaigns on larger islands, show the value and role of feral cat eradications in biodiversity conservation. However, new and more efficient techniques used in combination with current techniques will likely be needed for success on larger islands. Resumen:,Los gatos asilvestrados han sido responsables directos de un gran número de extinciones, particularmente en islas. En este estudio, se revisan los programas de erradicación de este felino con el fin de ofrecer información de utilidad en futuras acciones de conservación en islas. La mayor parte de las introducciones datan de los siglos diecinueve y veinte, mientras que las erradicaciones han sido realizadas básicamente durante los últimos 30 años, y sobre todo en la última década. Los gatos asilvestrados han sido erradicados de al menos 48 islas: 16 de ellas en Baja California (México), 10 en Nueva Zelanda, 5 en Australia, 4 en el Océano Pacífico, 4 en Seychelles, 3 en la Región Subantártica, 3 en Macaronesia (Océano Atlántico), 2 en Mauricio, y una en el Caribe. La mayoría de éstas (75%; n= 36) son de reducidas dimensiones (,5 km2), mientras que la más extensa es Marion Island (290 km2). En tan sólo 10 islas (21%) , 10 km2 se ha podido erradicar este depredador. En Cousine Island (Seychelles) la densidad de gatos alcanzó 243 individuos/km2; sin embargo, en la mayoría de las islas, las densidades no excedieron los 79,2 individuos/km2 (n= 22; 81%). Los métodos más comúnmente empleados fueron el trampeo y la caza, a menudo con perros (91% de un total de 43 islas). Con frecuencia dichas prácticas fueron empleadas conjuntamente. Otros métodos incluyeron venenos (1080, monofluoracetato de sodio en cebos de pescado: n= 13; 31%), envenenamiento secundario con ratas envenenadas (n= 4; 10%) y el virus de la leucemia felina (n= 2; 5%). La información sobre el efecto negativo de los gatos en islas y, más recientemente, el beneficio de su erradicación, se ha ido dando a conocer paulatinamente, poniendo de manifiesto su importancia en la conservación de la biodiversidad insular. No obstante, la combinación de técnicas nuevas y más eficientes junto con las habituales, será necesaria para el éxito de la erradicación de los gatos en islas de grandes dimensiones. [source]


Studying Biodiversity on Private Lands

CONSERVATION BIOLOGY, Issue 1 2003
Jodi Hilty
Private lands harbor a great amount of biodiversity, including at least some habitat for 95% of the federally listed species in the United States. It is important to conduct conservation biology research on private lands, but our review of the literature indicates that few conservation-oriented field studies are conducted on private property. Based on our success in obtaining permission to conduct research on 43 land parcels in Sonoma County, California, we developed methods to enhance a conservation biologist's chance of obtaining permission to work on private lands. We provide guidelines for researchers to conduct studies successfully on private land with the goal of improving access, data collection, and relationships with private landowners. We also discuss constraints researchers face, such as designing studies appropriate for working on privately owned parcels. In light of the importance of these lands to biodiversity conservation, greater effort should be made to conduct research on private lands. Resumen: Más de la mitad de la tierra en los Estados Unidos es propiedad privada. Las tierras de propiedad privada albergan una gran cantidad de biodiversidad, incluyendo al menos algunos hábitats para el 95% de las especies incluidas en la lista nacional de especies en peligro de extinción en los Estados Unidos. Es importante llevar a cabo investigación sobre biología de la conservación en tierras privadas, pero nuestra revisión de la literatura indica que existen pocos estudios a campo orientados hacia la conservación en propiedades privadas. En base a nuestro éxito en obtener permisos para llevar a cabo estudios de investigación en 43 parcelas de tierra en el condado de Sonoma, California, desarrollamos métodos para mejorar las posibilidades de los biólogos conservacionistas de obtener permisos para trabajar en tierras privadas. Hemos provisto lineamientos para que los investigadores lleven a cabo estudios exilosos en tierras privadas con el objeto de mejorar el acceso, la recolección de datos y las relaciones con los dueños de tierras privadas. También discutimos las limitantes que los investigadores enfrentan, tales como el diseño de estudios adecuados para trabajar en parcelas de propiedad privada. Dada la importancia de estas tierras para la conservación de la biodiversidad, se debería realizar un esfuerzo mayor para llevar a cabo investigaciones en tierras privadas. [source]


Roads, Development, and Conservation in the Congo Basin

CONSERVATION BIOLOGY, Issue 6 2000
David Wilkie
Research in the Republic of Congo shows that roads established and maintained by logging concessions intensify bushmeat hunting by providing hunters greater access to relatively unexploited populations of forest wildlife and by lowering hunters' costs to transport bushmeat to market. Reconciling the contrary effects of roads on economic development and biodiversity conservation is one of the key challenges to wildlife managers in all nations. As the Democratic Republic of Congo prepares to reconstruct its almost completely collapsed road system, the government, donors, and conservation organizations have a unique opportunity to strategically prioritize investment in segments of the network that would maximize local and national economic benefits while minimizing adverse effects on forest wildlife. Resumen: La densidad de carreteras está estrechamente ligada al acceso a mercados, el crecimiento económico, la explotación de recursos naturales, la fragmentación del hábitat, la deforestación y la desaparición de tierras y vida silvestre. Investigación en la República del Congo muestra que las carreteras establecidas y mantenidas por las concesiones para tala de árboles intensifican la cacería al proveer a los cazadores un mayor acceso a poblaciones forestales de vida silvestre relativamente sin explotar y al disminuir el costo de transporte de la carne obtenida por la caza hacia el mercado. La reconciliación de los efectos contrarios de las carreteras en el desarrollo económico y la conservación de la biodiversidad es uno de los retos clave para los manejadores de vida silvestre en todas las naciones. A medida que la República Democrática del Congo se prepara para reconstruir su casi completamente colapsado sistema carretero, el gobierno, los donadores y las organizaciones no gubernamentales conservacionistas tienen una oportunidad única para priorizar estratégicamente las inversiones en segmentos de la red carretera que podrían maximizar los beneficios económicos locales y nacionales al mismo tiempo que se minimicen los impactos adversos sobre la vida silvestre forestal. [source]


Cacao boom and bust: sustainability of agroforests and opportunities for biodiversity conservation

CONSERVATION LETTERS, Issue 5 2009
Yann Clough
Abstract Cacao cultivation holds a sweet promise, not only for chocolate consumers and cacao farmers but also for conservationists who argue that diverse cacao agroforests may be used to sustain both livelihoods of smallholders and ecological benefits such as the conservation of biodiversity within human-dominated tropical landscapes. However, regional boom-and-bust cycles are the rule in global cacao production: after initial forest conversion to cacao agroforests, sustaining production is difficult due to dwindling yields as trees age and pest and disease pressure increases. The failure to revitalize plantations often leads to a shift of cacao production to other regions. Shade removal dynamics within these cycles substantially reduce most of the biodiversity benefits. We investigate the conservation implications of these processes. Using examples from the current cacao crisis in Indonesia, we show that until now commitments to sustainability by the cacao-chocolate sector have not been successful, which endangers remaining forests. Conservation can be combined with smallholder cacao production, but if this is to be achieved, greater quantitative and qualitative efforts to halt cacao cycles are needed on the part of the industry by making use of existing opportunities to combine sustainability, carbon storage, and biodiversity conservation. [source]


Conservation biogeography , foundations, concepts and challenges

DIVERSITY AND DISTRIBUTIONS, Issue 3 2010
David M. Richardson
Abstract Conservation biogeography involves the application of biogeographical principles, theories, and analyses to problems regarding biodiversity conservation. The field was formally defined in 2005, and considerable research has been conducted in the ensuing 5 years. This editorial sets the context for 16 contributions in a special issue of Diversity and Distributions on developments and challenges in conservation biogeography. Papers are grouped into the following main themes: species distribution modelling; data requirements; approaches for assigning conservation priorities; approaches for integrating information from numerous disparate sources; special challenges involving invasive species; and the crucial issue of determining how elements of biodiversity are likely to respond to rapid climate change. One paper provides a synthesis of requirements for a robust conservation biogeography for freshwater ecosystems. Conservation biogeography is well poised to make a significant contribution to the process of providing policy makers with objectively formulated scenarios and options for the effective management of biodiversity. The editorial, and the papers in the special issue, deliberate on many of the exciting developments in play in the field, and the many complex challenges that lie ahead. [source]


The geography of climate change: implications for conservation biogeography

DIVERSITY AND DISTRIBUTIONS, Issue 3 2010
D. D. Ackerly
Abstract Aim, Climate change poses significant threats to biodiversity, including impacts on species distributions, abundance and ecological interactions. At a landscape scale, these impacts, and biotic responses such as adaptation and migration, will be mediated by spatial heterogeneity in climate and climate change. We examine several aspects of the geography of climate change and their significance for biodiversity conservation. Location, California and Nevada, USA. Methods, Using current climate surfaces (PRISM) and two scenarios of future climate (A1b, 2070,2099, warmer-drier and warmer-wetter), we mapped disappearing, declining, expanding and novel climates, and the velocity and direction of climate change in California and Nevada. We also examined fine-scale spatial heterogeneity in protected areas of the San Francisco Bay Area in relation to reserve size, topographic complexity and distance from the ocean. Results, Under the two climate change scenarios, current climates across most of California and Nevada will shrink greatly in extent, and the climates of the highest peaks will disappear from this region. Expanding and novel climates are projected for the Central Valley. Current temperature isoclines are projected to move up to 4.9 km year,1 in flatter regions, but substantially slower in mountainous areas because of steep local topoclimate gradients. In the San Francisco Bay Area, climate diversity within currently protected areas increases with reserve size and proximity to the ocean (the latter because of strong coastal climate gradients). However, by 2100 of almost 500 protected areas (>100 ha), only eight of the largest are projected to experience temperatures within their currently observed range. Topoclimate variability will further increase the range of conditions experienced and needs to be incorporated in future analyses. Main Conclusions, Spatial heterogeneity in climate, from mesoclimate to topoclimate scales, represents an important spatial buffer in response to climate change, and merits increased attention in conservation planning. [source]


Wilderness and future conservation priorities in Australia

DIVERSITY AND DISTRIBUTIONS, Issue 6 2009
James E.M. Watson
Abstract Aim, Most approaches to conservation prioritization are focused on biodiversity features that are already threatened. While this is necessary in the face of accelerating anthropogenic threats, there have been calls to conserve large intact landscapes, often termed ,wilderness', to ensure the long-term persistence of biodiversity. In this study, we examine the consequences of directing conservation expenditure using a threat-based framework for wilderness conservation. Location, The Australian continent. Methods, We measured the degree of congruence between the extent of wilderness and the Australian protected area network in 2000 and 2006, which was established using a threat-based systematic planning framework. We also assessed priority areas for future reserve acquisitions identified by the Australian government under the current framework. Results, In 2000, 14% of Australia's wilderness was under formal protection, while the protected area network covered only 8.5% of the continent, suggesting a historical bias towards wilderness protection. However, the expansion of the reserve system from 2000 to 2006 was biased towards non-wilderness areas. Moreover, 90% of the wilderness that was protected over this period comprised areas not primarily designated for biodiversity conservation. We found a significant (P < 0.05) negative relationship between bioregions considered to be a priority for future reserve prioritization and the amount of wilderness they contain. Main conclusions, While there is an urgent need to overcome past biases in reserve network design so as to better protect poorly represented species and habitats, prioritization approaches should not become so reactive as to ignore the role that large, intact landscapes play in conserving biodiversity, especially in a time of human-induced climate change. This can be achieved by using current or future threats rather than past threats to prioritize areas, and by incorporating key ecological processes and costs of acquisition and management within the planning framework. [source]


Where do Swainson's hawks winter?

DIVERSITY AND DISTRIBUTIONS, Issue 5 2008
Satellite images used to identify potential habitat
ABSTRACT During recent years, predictive modelling techniques have been increasingly used to identify regional patterns of species spatial occurrence, to explore species,habitat relationships and to aid in biodiversity conservation. In the case of birds, predictive modelling has been mainly applied to the study of species with little variable interannual patterns of spatial occurrence (e.g. year-round resident species or migratory species in their breeding grounds showing territorial behaviour). We used predictive models to analyse the factors that determine broad-scale patterns of occurrence and abundance of wintering Swainson's hawks (Buteo swainsoni). This species has been the focus of field monitoring in its wintering ground in Argentina due to massive pesticide poisoning of thousands of individuals during the 1990s, but its unpredictable pattern of spatial distribution and the uncertainty about the current wintering area occupied by hawks led to discontinuing such field monitoring. Data on the presence and abundance of hawks were recorded in 30 × 30 km squares (n = 115) surveyed during three austral summers (2001,03). Sixteen land-use/land-cover, topography, and Normalized Difference Vegetation Index (NDVI) variables were used as predictors to build generalized additive models (GAMs). Both occurrence and abundance models showed a good predictive ability. Land use, altitude, and NDVI during spring previous to the arrival of hawks to wintering areas were good predictors of the distribution of Swainson's hawks in the Argentine pampas, but only land use and NDVI were entered into the model of abundance of the species in the region. The predictive cartography developed from the models allowed us to identify the current wintering area of Swainson's hawks in the Argentine pampas. The highest occurrence probability and relative abundances for the species were predicted for a broad area of south-eastern pampas that has been overlooked so far and where neither field research nor conservation efforts aiming to prevent massive mortalities has been established. [source]


Effects of landscape structure and habitat type on a plant-herbivore-parasitoid community

ECOGRAPHY, Issue 3 2003
Andreas Kruess
The effects of local habitat and large-scale landscape factors on species diversity and species interactions were studied using the insect community in stems of the creeping thistle Cirsium arvense. Thistle abundance was higher in fallows than in crop fields and field margins, with fallows providing 67% of thistle abundance within 15 study areas on a landscape scale. Species richness of the herbivores was positively related with thistle abundance, parasitoid species richness was influenced by habitat type and was positively correlated with herbivore species richness. The abundance of herbivores and parasitoids was affected by local factors such as habitat type and host abundance, but also by landscape factors such as the percentage of non-crop area and the isolation of habitats. The infestation rate caused by the agromyzid Melanagromyza aeneoventris was positively related to percent non-crop area, whereas the parasitism rate of this fly increased with increasing habitat diversity on the landscape scale. For these two interactions and for total herbivore abundance, a scale-dependency of the landscape effects was found. The results emphasize that biological diversity and ecological functions within a plant-insect community are not only affected by local habitat factors but also by large-scale landscape characteristics. Hence, to improve future agri-environmental schemes for biodiversity conservation and biological control large-scale landscape effects and their scale-dependency should be considered. [source]


Assessing the habitat quality of oil mallees and other planted farmland vegetation with reference to natural woodland

ECOLOGICAL MANAGEMENT & RESTORATION, Issue 3 2009
F. Patrick Smith
Summary, Much of the tree and shrub planting that has been conducted on farms in Western Australia over the past three decades has not been done with the specific intention of creating habitat or conserving biodiversity, particularly commercially oriented monocultures like oil mallee plantings. However, such plantings may nonetheless provide some habitat resources for native plants and animals. This study assessed the habitat quality of farm plantings (most of which were not planted with the primary intention of biodiversity conservation) at 72 sites across a study region in the central wheatbelt of Western Australia. Widely accepted habitat metrics were used to compare the habitat resources provided by planted farmland vegetation with those provided by remnant woodland on the same farms. The impact of adjacency of plantings to woodland and, in the case of oil mallees, the planting configuration on predicted habitat quality is assessed. Condition Benchmarks for five local native vegetation communities are proposed. Farmland plantings achieved an average Vegetation Condition Score (VCS) of 46 out of a possible 100, while remnant woodland on the same farms scored an average 72. The average scores for farm plantings ranged from 38,59 depending on which of five natural vegetation communities was used as its benchmark, but farm plantings always scored significantly less than remnant woodland (P < 0.001). Mixed species plantings on average were rated more highly than oil mallees (e.g. scores of 42 and 36 respectively using the Wandoo benchmark) and adjacency to remnant woodland improved the score for mixed plantings, but not for oil mallees. Configuration of oil mallees as blocks or belts (i.e. as an alley farming system) had no impact on the VCS. Planted farmland vegetation fell short of remnant woodland in both floristic richness (51 planted native species in total compared with a total of more than 166 naturally occurring plant species in woodland) and structural diversity (with height, multiple vegetation strata, tree hollows and woody debris all absent in the relatively young 7,15-year-old farm plantings). Nonetheless farmland plantings do have measurable habitat values and recruitment and apparent recolonization of plantings with native plant species was observed. Habitat values might be expected to increase as the plantings age. The VCS approach, including the application of locally relevant Benchmarks is considered to be valuable for assessing potential habitat quality in farmland vegetation, particularly as a tool for engaging landholders and natural resource management practitioners. [source]