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71.
Numerous road and railway construction projects include costly mitigation measures to offset the barrier effect produced on local fauna, despite the scarcity of data on the effectiveness of such mitigation measures. In this study, we evaluate the utility of different types of crossing structures. Vertebrate use of 43 transverse crossing structures along the A-52 motorway (north-western Spain) was studied during spring 2001. Research centered on wildlife passages (9), wildlife-adapted box culverts (7), functional passages (6 overpasses, 7 underpasses) and culverts (14), with marble dust being used to record animal tracks. A total of 424 track-days were recorded, with most of the larger vertebrate groups present in the area being detected. All crossing structure types were used by animals, although the intensity of use varied significantly among them (Kruskal-Wallis test, p<0.05); culverts were used less frequently than other structures. Crossing structure type and width were identified as the most important factors in their selection for use. Wildlife passages and adapted culverts allowed crossing by certain species (wild boar, roe deer, Eurasian badger), which do not tend to cross elsewhere. These results highlight the importance of using both mixed-type structures and wildlife passages in reducing the barrier effect of roads.  相似文献   
72.
The Iberian wild goat (Capra pyrenaica), an endemic species to the Iberian Peninsula, was represented in the past by four subspecies. Currently, the conservation status of the recognized subspecies - C. p. hispanica and C. p. victoriae - is quite different, being the former broadly distributed while the latter inhabits fewer and smaller areas. In this global context, our specific aims were to assess the biogeographical relationships, similarities and differences between the Iberian wild goat subspecies, and to evaluate their conservation status from a biogeographical perspective. We modelled the ecogeographical favourability for each subspecies, and also for the whole species, and we comparatively analyzed the spatial relationships among models in order to detect differential biogeographical patterns. Our results showed a differential pattern for each Iberian wild goat subspecies, and thus each one should be independently considered when designing management strategies. The distribution of C. p. victoriae was closely related to climatic conditions, thus it is highly sensitive to variations in climatic characteristics. Finally, from the perspective of metapopulation theory, and according to the geographical structure of their favourable areas, C. p. victoriae is at higher risk than C. p. hispanica. We discuss the implications of our results for species/subspecies conservation, and highlight the importance of conservation biogeography.  相似文献   
73.
Recently, new approaches to wildlife management are being developed, such as coexistence management and convivial conservation. These approaches aim to shift management practices from mitigating human–wildlife conflicts towards cohabitation and explore mutual benefits. To align empirical research to these new approaches, we argue for the relevance of positive psychology theory to inspire and structure research into the benefits of human–wildlife interactions. Positive psychology suggests three pathways through which human–wildlife interactions may lead to happiness and well-being: pleasure, engagement, and meaning. Applying these pathways to human–wildlife research may (i) structure existing research into the benefits of human–wildlife interactions, (ii) disclose unidentified benefits of human–wildlife interactions, and (iii) unravel mechanisms which make experiencing and protecting wildlife worthwhile and rewarding. Also, we suggest a potential feedback loop between wildlife experiences, happiness and well-being, and pro-environmental behaviours. More in-depth research into these mechanisms may improve our understanding of attitudes towards conservation of wildlife and its habitat and may suggest strategies to strengthen stewardship actions and public support for conservation strategies. Together, these strands of research could initiate research into what could be called a “Positive Ecology”.  相似文献   
74.
The use of poison to eliminate predators is causing African vulture populations to collapse. To understand the prevalence and motivations of this practice we conducted an extensive survey with South African commercial farmers. Using a specialised questioning technique and ad hoc quantitative methods we found that an estimated 22% and 31% of farmers used poison over a 1-year and 5-year period, respectively. Poison use hotspots generally coincided with small stock farming areas. The strongest predictor of poison use was whether farmers believed the practice to be common amongst their peers. Our results suggest that farmers’ attitudes to vultures are primarily positive, and farmers are less likely to use poisons if they frequently encounter vultures on their farm. Overall, our findings provide an understanding on poison use that provides leverage points to change farmers’ behaviour and help avert the African vulture crisis and possible cascading ecosystem impacts.Supplementary informationThe online version of this article (10.1007/s13280-020-01461-2) contains supplementary material, which is available to authorized users.  相似文献   
75.
The Endangered Species Act (ESA) of the United States was enacted in 1973 to prevent the extinction of species. Recovery plans, required by 1988 amendments to the ESA, play an important role in organizing these efforts to protect and recover species. To improve the use of science in the recovery planning process, the Society for Conservation Biology (SCB) commissioned an independent review of endangered species recovery planning in 1999. From these findings, the SCB made key recommendations for how management agencies could improve the recovery planning process, after which the U.S. Fish and Wildlife Service and the National Marine Fisheries Service redrafted their recovery planning guidelines. One important recommendation called for recovery plans to make threats a primary focus, including organizing and prioritizing recovery tasks for threat abatement. We sought to determine the extent to which results from the SCB study were incorporated into these new guidelines and whether the SCB recommendations regarding threats manifested in recovery plans written under the new guidelines. Recovery planning guidelines generally incorporated the SCB recommendations, including those for managing threats. However, although recent recovery plans have improved in their treatment of threats, many fail to adequately incorporate threat monitoring. This failure suggests that developing clear guidelines for monitoring should be an important priority in improving ESA recovery planning.  相似文献   
76.
Wildlife use is a strategy for livelihood diversification, and markets depend on the characteristics of consumers and providers as well as on regional socioeconomic variables, such as the accommodation infrastructure, population density, land use, and economic activities, which are all aspects considered in this study. In Mexico wildlife subsidy is applied with general criteria and economic information related to wildlife uses is scarce. Assessing a municipality's socioeconomic characteristics and the probability of the occurrence of Wildlife Management Units (UMAs) in Mexico provides useful information for identifying the present conditions that have an influence on the location and development of UMAs providing useful information for decision making. Geographical and socioeconomic approaches for describing the distribution of UMAs can lead to better decisions related to focalization and therefore to the improvement of wildlife and environmental policies that have an influence on livelihood quality.  相似文献   
77.
Global positioning system (GPS) collars have revolutionized the collection of animal location data; however, it is well-recognized that considerable bias can be present in these data due to habitat or behavior-induced obstruction of satellite signals resulting in inaccurate or missing locations. To date, no explicit theoretical framework of GPS fix acquisition specific to animal telemetry has been presented, and studies make differing assumptions regarding factors influencing GPS fix acquisition and how these data should be analyzed. Inappropriate statistical models have been used, interaction effects have been misunderstood, and the implementation of bias mitigation techniques has been problematic. Herein we outline current conceptual and analytical problems in the GPS animal telemetry literature, and subsequently present a theoretical model-based framework for GPS fix acquisition that clarifies the single and interactive effects of habitat and behavioral obstruction, fix interval, and collar model on GPS collar performance. By recognizing that GPS fix acquisition is a Bernoulli process, it becomes apparent that all forms of obstruction inherently interact with each other, making generalizations across study areas, study species, and collar models problematic. Stationary collar tests to determine the probability of fix acquisition (PFA), location accuracy, and the response to sources of obstruction are thus of limited applicability to animal-deployed collars. Bias mitigation techniques that extrapolate PFA models across samples, especially those using stationary collar tests to correct animal-deployed collars, are theoretically unsound. It is also demonstrated that nonlinearities in the relationships between sources of obstruction and PFA complicate PFA modeling with limited data and that even slight model misspecification can lead to considerable errors in correction factors, especially when using inverse weighting to mitigate bias. By emphasizing the importance of GPS collar sensitivity and ephemeris retention, the theoretical framework predicts that newer, more sensitive GPS collars will be less severely biased by sources of obstruction than reported for the older, less sensitive collars that have been used in the majority of GPS performance studies to date and we expect this trend to continue. This heuristic modeling exercise should be of value to researchers planning and analyzing studies using GPS collars and it also establishes a starting point for future theoretical investigations into GPS collar performance and bias mitigation.  相似文献   
78.
This paper examines the effects of wildlife tourism‐based payments for ecosystem services (PES) on poverty, wealth inequality and the livelihoods of herders in the Maasai Mara Ecosystem in south‐western Kenya. It uses the case of Olare Orok Conservancy PES programme in which pastoral landowners have agreed to voluntary resettlement and exclusion of livestock grazing from their sub‐divided lands. These lands are set aside for wildlife tourism, in return for direct monetary payments by a coalition of five commercial tourism operators. Results show that, on the positive side, PES is the most equitable income source that promotes income diversification and buffers households from the livestock income declines during periods of severe drought, such as in 2008‐2009. Without accounting for the opportunity costs, the magnitude of the PES cash transfer to households is, on average, sufficient to close the poverty gap. The co‐benefits of PES implementation include the creation of employment opportunities in the conservancy and provision of social services. There is however a need to mitigate the negative effects of PES, including the widening inequality in income between PES and non‐PES households and the leakages resulting from the displacement of settlements and livestock to currently un‐subdivided pastoral commons.  相似文献   
79.
Not all disease activity causes an impact. Not all impacts are negative. The aim of this study was to examine a method that could conceptually specify when impacts occur and that could quantify both negative and positive disease impacts. For this study, dwarf mistletoe (Arceuthobium douglasi) of Douglas fir (Pseudotsuga menziesii) in southwestern Oregon was used as a case study. The method uses six variables for forest growth, mortality, and stand structure, and six categorical disease severity scores. The impact model displays stands as points in multidimensional scaling space, where relative position is determined by values of the six stand variables. Positions in this two-dimensional space change when stand characteristics change. Differences associated with disease severity could be traced as trajectories, and impact was quantified using the length and direction of these trajectories. This multivariate impact assessment method was contrasted to impact assessments based on single variables. Methods based on multiple variables offer a useful way of characterizing impact on multiple objectives. The model indicates that dwarf mistletoe has positive, negative, and neutral impacts and that these could be illustrated and quantified using this method.  相似文献   
80.
An alternative method of estimating relative demand among nonconsumptive uses of wildlife and among wildlife species is proposed. A demand intensity score (DIS), derived from the relative extent of an individual's involvement in outdoor recreation and conservation activities, is used as a weighting device to adjust the importance of preference rankings for wildlife uses and wildlife species relative to other members of a survey population. These adjusted preference rankings were considered to reflect relative demand levels (RDLs) for wildlife uses and for species by the survey population. This technique may be useful where it is not possible or desirable to estimate demand using traditional economic means. In one of the findings from a survey of municipal conservation commission members in Massachusetts, presented as an illustration of this methodology, poisonous snakes were ranked third in preference among five groups of reptiles. The relative demand level for poisonous snakes, however, was last among the five groups.  相似文献   
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