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Conservation Approach (conservation + approach)
Selected AbstractsA 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] Payments for Ecosystem Services in Nicaragua: Do Market-based Approaches Work?DEVELOPMENT AND CHANGE, Issue 3 2010Gert Van Hecken ABSTRACT The concept of Payments for Ecosystem Services (PES) is gaining increasing attention among scholars as well as conservation and development practitioners. The premises of this innovative conservation approach are appealing: private land users, usually poorly motivated to protect nature on their land, will do so if they receive payments from environmental service buyers which cover part of the land users' opportunity costs of developing the land. However, this article warns against an over-enthusiastic adoption of a one-sided market-based PES approach. Based on a field study of the Regional Integrated Silvopastoral Approaches to Ecosystem Management Project (RISEMP), one of the main PES pilot projects in Nicaragua, it suggests that a mixture of economic and non-economic factors motivated farmers to adopt the envisaged silvopastoral practices and that the actual role of PES is mistakenly understood as a simple matter of financial incentives. The authors argue that PES approaches should be understood as a part of a broader process of local institutional transformation rather than as a market-based alternative for allegedly ineffective government and/or community governance. [source] Potential impacts of climate change on Sub-Saharan African plant priority area selectionDIVERSITY AND DISTRIBUTIONS, Issue 6 2006Colin J. McClean ABSTRACT The Global Strategy for Plant Conservation (GSPC) aims to protect 50% of the most important areas for plant diversity by 2010. This study selects sets of 1-degree grid cells for 37 sub-Saharan African countries on the basis of a large database of plant species distributions. We use two reserve selection algorithms that attempt to satisfy two of the criteria set by the GSPC. The grid cells selected as important plant cells (IPCs) are compared between algorithms and in terms of country and continental rankings between cells. The conservation value of the selected grid cells are then considered in relation to their future species complement given the predicted climate change in three future periods (2025, 2055, and 2085). This analysis uses predicted climate suitability for individual species from a previous modelling exercise. We find that a country-by-country conservation approach is suitable for capturing most, but not all, continentally IPCs. The complementarity-based reserve selection algorithms suggest conservation of a similar set of grid cells, suggesting that areas of high plant diversity and rarity may be well protected by a single pattern of conservation activity. Although climatic conditions are predicted to deteriorate for many species under predicted climate change, the cells selected by the algorithms are less affected by climate change predictions than non-selected cells. For the plant species that maintain areas of climatic suitability in the future, the selected set will include cells with climate that is highly suitable for the species in the future. The selected cells are also predicted to conserve a large proportion of the species richness remaining across the continent under climate change, despite the network of cells being less optimal in terms of future predicted distributions. Limitations to the modelling are discussed in relation to the policy implications for those implementing the GSPC. [source] Conservation laryngeal surgery versus total laryngectomy for radiation failure in laryngeal cancer,HEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 9 2006F. Christopher Holsinger MD Abstract Background. Total laryngectomy is the standard of care for surgical salvage of radiation failure in laryngeal cancer. However, the role of conservation laryngeal surgery in this setting remains unclear. The objective was to compare the efficacy of conservation versus total laryngectomy for salvage of radiation failure in patients who initially presented with T1 or T2 squamous cancer of the larynx. Methods. A 21-year retrospective analysis of patients who received surgery at a single comprehensive cancer center after definitive radiation therapy is reported. At recurrence, the patients were reevaluated and then underwent a total laryngectomy or, if possible, a conservation laryngeal procedure. The charts of 105 patients who failed radiation treatment for primary laryngeal cancer and who subsequently underwent surgical salvage were reviewed for this study. Eighty-nine were male (84.8%). The mean age was 60.3 years. The median follow-up time after surgery was 69.4 months. Most patients with recurrence after radiotherapy required total laryngectomy (69.5%; 73/105). Conservation laryngeal surgery was performed for 32 patients (31.5%). Concomitant neck dissections were performed on 45 patients (45.5%). Results. In 14 patients, local or regional recurrence developed after salvage surgery: 9 patients after total laryngectomy (12.3%; 9/73), and 5 patients (15.6%; 5/32) after conservation laryngeal surgery. This difference was not statistically significant, nor was there a difference in disease-free interval for the two procedures (p = .634, by log-rank test). Distant metastasis developed in 13 patients. Most developed in the setting of local and/or regional recurrence, but distant metastasis occurred as the only site of failure in 6 of the patients who had undergone total laryngectomy but in 1 of the conservation surgery patients treated for a supraglottic laryngeal cancer. The overall mortality for patients who underwent total laryngectomy was also higher: 73.74% (54/73) versus 59.4% (19/32) for patients who underwent a conservation approach (p = .011 by log-rank test). Conclusions. Although conservation laryngeal surgery was possible in a few patients with local failure after radiotherapy, conservation laryngeal surgery is an oncologically sound alternative to total laryngectomy for these patients. © 2006 Wiley Periodicals, Inc. Head Neck, 2006 [source] Calibrating conservation: new tools for measuring successCONSERVATION LETTERS, Issue 4 2008Valerie Kapos Abstract Conservation practitioners, policy makers, and donors agree that there is an urgent need to identify which conservation approaches are most likely to succeed in order to use more effectively the limited resources available for conservation. While recently developed standards of good practice in conservation are helpful, a framework for evaluation is needed that supports systematic analysis of conservation effectiveness. A conceptual framework and scorecard developed by the Cambridge Conservation Forum help to address common constraints to evaluating conservation success: unclear objectives, ineffective information management, the long time frames of conservation outcomes, scarcity of resources for evaluation, and lack of incentives for such evaluation. For seven major categories of conservation activity, the CCF tools help clarify conservation objectives and provide a standardized framework that is a useful basis for managing information about project outcomes and existing conservation experience. By identifying key outcomes that can predict conservation success and can be assessed in relatively short time frames, they help to make more efficient use of scarce monitoring and evaluation resources. With wide application, the CCF framework and evaluation tool can provide a powerful platform for drawing on the experience of past and ongoing conservation projects to identify quantitatively factors that contribute to conservation success. [source] Partitioned Nature, Privileged Knowledge: Community-based Conservation in TanzaniaDEVELOPMENT AND CHANGE, Issue 5 2003Mara Goldman Community Based Conservation (CBC) has become the catch,all solution to the social and ecological problems plaguing traditional top,down, protectionist conservation approaches. CBC has been particularly popular throughout Africa as a way to gain local support for wildlife conservation measures that have previously excluded local people and their development needs. This article shows that, despite the rhetoric of devolution and participation associated with new CBC models, conservation planning in Tanzania remains a top,down endeavour, with communities and their specialized socio,ecological knowledge delegated to the margins. In addition to the difficulties associated with the transfer of power from state to community hands, CBC also poses complex challenges to the culture or institution of conservation. Using the example of the Tarangire,Manyara ecosystem, the author shows how local knowledge and the complexities of ecological processes challenge the conventional zone,based conservation models, and argues that the insights of local Maasai knowledge claims could better reflect the ecological and social goals of the new CBC rhetoric. [source] Managing the matrix for large carnivores: a novel approach and perspective from cheetah (Acinonyx jubatus) habitat suitability modellingANIMAL CONSERVATION, Issue 1 2006J. R. Muntifering Abstract Effective management within the human-dominated matrix, outside of formally protected areas, is of paramount importance to wide-ranging carnviores. For instance, the largest extant population of cheetahs Acinonyx jubatus currently persists on privately owned Namibian ranchlands, and provides an excellent case study to examine and design matrix conservation approaches. Although human-caused mortality is likely the principal threat to this population, ancedotal evidence suggests that ,bush encroachment', the widespread conversion of mixed woodland and savannah habitats to dense, Acacia -dominated thickets, is another probable threat. A better understanding of cheetah habitat use, outside of protected areas, could be used to directly influence habitat management strategies and design local restoration and conflict mitigation efforts. To identify specific habitat characteristics associated with cheetah use, we used radio-telemetry locations to identify areas used intensively by cheetahs on commercial Namibian farms. We then compared the habitat characteristics of these ,high-use' areas with adjacent ,low-use' areas. A binary logistic regression model correctly categorized 92% of plot locations as high or low use, and suggested that cheetahs may be utilizing ,rewarding patches' with better sighting visibility and greater grass cover. We discuss the possible reasons for kudu Tragelaphus strepsiceros, Namibian cheetahs' preferred prey, exhibiting significantly lower abundance in high-use areas. Using habitat characteristics to identify areas intensively utilized by cheetahs has important implications for guiding future habitat restoration and developing effective predator conflict mitigation efforts. [source] Genetic diversity of dog breeds: between-breed diversity, breed assignation and conservation approachesANIMAL GENETICS, Issue 3 2009G. Leroy Summary Genetic relationships between 61 dog breeds were investigated, using a sampling of 1514 animals and a panel of 21 microsatellite markers. Based on the results from distance-based and Bayesian methods, breed constituted the main genetic structure, while groups including genetically close breeds showed a very weak structure. Depending on the method used, between 85.7% and 98.3% of dogs could be assigned to their breed, with large variations according to the breed. However, breed heterozygosity influenced assignment results differently according to the method used. Within-breed and between-breed diversity variations when breeds were removed were highly negatively correlated (r = ,0.963, P < 0.0001), because of the genetic structure of the breed set. [source] | ||||||||||