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41.
Laura R. Perry Tom P. Moorhouse Andrew J. Loveridge David W. Macdonald 《Conservation biology》2020,34(4):879-890
Conflict between people and carnivores can lead to the widespread killing of predators in retaliation for livestock loss and is a major threat to predator populations. In Kenya, a large, rural, pastoralist population comes into regular conflict with predators, which persist across southern Kenya. We explored the social and psychological backdrop to livestock management practices in this area in a process designed to be easy to use and suitable for use across large areas for the study of conflict and transboundary implementation of wildlife conflict reduction measures, focusing on community involvement and needs. We carried out fully structured interviews of livestock managers with a survey tool that examined how social and psychological factors may influence livestock management behavior. We compared survey responses on 3 sites across the study area, resulting in 723 usable responses. Efficacy of individuals’ livestock management varied between and within communities. This variation was partially explained by normative and control beliefs regarding livestock management. Individual livestock managers’ self-reported management issues were often an accurate reflection of their practical management difficulties. Psychological norms, control beliefs, and attitudes differed among sites, and these differences partially explained patterns associated with conflict (i.e., variation in livestock management behavior). Thus, we conclude that a one-size-fits-all approach to improving livestock management and reducing human–predator conflict is not suitable. 相似文献
42.
Mohammad S. Farhadinia Paul J. Johnson Alexandra Zimmermann Philip J.K. McGowan Erik Meijaard Mark Stanley-Price David W. Macdonald 《Conservation biology》2020,34(4):988-996
The persistence of endangered species may depend on the fate of a very small number of individual animals. In situ conservation alone may sometimes be insufficient. In these instances, the International Union for Conservation of Nature provides guidelines for ex situ conservation and the Convention on Biological Diversity (CBD) indicates how ex situ management can support the CBD's objectives by providing insurance policies for species. The circumstances that justify its use are uncertain. To evaluate the current in situ extinction risk and ex situ management of 43 critically endangered species of mammalian megafauna, we used nonmetric multidimensional scaling and geopolitical variables related to governance, economics, and national policy within their extant ranges. We then fitted generalized additive models to assess the contribution of each variable to the ordination. Fifteen (almost one-third) of the world's terrestrial mammalian megafauna are not the subject of any ex situ management. Seventy-three percent of these taxa occur in areas characterized by political uncertainty, such as border zones or areas affected by armed conflicts, mainly in Africa and the Middle East. A further 23% of taxa in ex situ programs do not meet sustainability criteria for inbreeding avoidance. Strategic conservation planning, such as the One Plan approach, may improve ex situ management for these taxa. Given the escalating trend in threats afflicting megafauna, ex situ management should be considered more rigorously, particularly in politically unstable regions, to achieve CBD Target 12 (prevent extinction of threatened species). 相似文献
43.
This paper presents a hedonic property price model of rural land in a natural resource management region of the Murray-Darling Basin in Australia. In traditional hedonic models, the marginal value of environmental amenities is estimated using distance to or size of the environmental asset. The approach applied in this study offers the potential for a richer set of information, where environmental assets are described in terms of their 'recreational attractiveness'. The level of recreational attractiveness is represented as latent variables that are based on park facilities and recreational activities offered at each site. For a property in the study area that is 1?km away from the River Murray, moving half a kilometre closer will increase the property price by $245,000, holding every other variable constant at the mean. This value is magnified by $27,000 if the house is in an area where there is high river recreational attractiveness and drops by $14,000 if river recreational attractiveness is low. By including recreational quality indices in a typical hedonic framework that is corrected for spatial dependency, the model is able to capture how individuals value environmental amenities around their homes based on the site's natural characteristics as well as recreational services. 相似文献
44.
Duncan Macdonald Kaveh Sanati Ewan Macdonald 《International journal of occupational safety and ergonomics》2013,19(4):587-590
AbstractOccupational injuries requiring admission to a trauma unit were examined to outline the events surrounding the injury and to examine the costs. Sixty-nine patients were admitted over a 12-month period, representing 4.30% of all work-related injuries attending the emergency department and 4.25% of all admissions to the trauma unit. Most were male (91%), working in skilled trade occupations (65%), with a mean age of 38.8 years. Personal protective equipment was used only by 46% of injured workers who should have been using it. Sixty-one percent of patients believed that their injury was preventable. Half of the injuries were to the upper limb, fall was the most frequent mechanism (25%) and the median duration of admission was 2 days. The direct hospital costs were estimated at over 300 000 GBP. Failure to use protective equipment and to follow health and safety guidelines suggests that opportunities exist for injury prevention. 相似文献
45.
Incidence of adverse biological effects within ranges of chemical concentrations in marine and estuarine sediments 总被引:118,自引:0,他引:118
Edward R. Long Donald D. Macdonald Sherri L. Smith Fred D. Calder 《Environmental management》1995,19(1):81-97
Matching biological and chemical data were compiled from numerous modeling, laboratory, and field studies performed in marine
and estuarine sediments. Using these data, two guideline values (an effects range-low and an effects range-median) were determined
for nine trace metals, total PCBs, two pesticides, 13 polynuclear aromatic hydrocarbons (PAHs), and three classes of PAHs.
The two values defined concentration ranges that were: (1) rarely, (2) occasionally, or (3) frequently associated with adverse
effects. The values generally agreed within a factor of 3 or less with those developed with the same methods applied to other
data and to those developed with other effects-based methods. The incidence of adverse effects was quantified within each
of the three concentration ranges as the number of cases in which effects were observed divided by the total number of observations.
The incidence of effects increased markedly with increasing concentrations of all of the individual PAHs, the three classes
of PAHs, and most of the trace metals. Relatively poor relationships were observed between the incidence of effects and the
concentrations of mercury, nickel, total PCB, total DDT and p,p′-DDE. Based upon this evaluation, the approach provided reliable
guidelines for use in sediment quality assessments. This method is being used as a basis for developing National sediment
quality guidelines for Canada and informal, sediment quality guidelines for Florida.
The methods and guidelines presented in this report do not necessarily represent the policy of the National Oceanic and Atmospheric
Administration, Environment Canada, or Florida Department of Environmental Protection. 相似文献
46.
47.
P. Stockley J. B. Searle D. W. Macdonald C. S. Jones 《Behavioral ecology and sociobiology》1994,34(1):71-78
The common shrew (Sorex araneus) is a solitary small mammal with a promiscuous mating system. Previous studies of this species suggest that females typically mate multiply, and that males may adopt alternative mate-searching tactics. We studied two generations of common shrews in a population near Oxford, England. Males were found to adopt two different mate-searching tactics. Those classed as type A occupied relatively small exclusive ranges during March, and made repeated long-distance movements to visit female ranges around the time of first oestrus in April. Males classed as type B established large overlapping ranges in areas of relatively high female density during March, and maintained these ranges throughout April. Type B males were larger than type A males at an early stage of sexual maturation, but there was no difference in the adult body size of the two types of male. Type A males had significantly higher epididymal sperm counts than type B males. Paternity analyses of litters born during the first year of the study reveal that the mean number of offspring fathered by type B males was greater than the mean number fathered by type A males. It is concluded that different mate-searching tactics may be conditional upon the timing of sexual maturation. Differences in sperm production are discussed in relation to sperm competition theory. 相似文献
48.
David S. L. Ramsey Karl J. Campbell Christian Lavoie Norm Macdonald Scott A. Morrison 《Conservation biology》2022,36(4):e13898
The Judas technique is often used in control or eradication of particular vertebrate pests. The technique exploits the tendency of individuals to form social groups. A radio collar is affixed to an individual and its subsequent monitoring facilitates the detection of other conspecifics. Efficacy of this technique would be improved if managers could estimate the probability that a Judas individual would detect conspecifics. To calculate this probability, we estimated association rates of Judas individuals with other Judas individuals, given the length of time the Judas has been deployed. We developed a simple model of space-use for individual Judas animals and constrained detection probabilities to those specific areas. We then combined estimates for individual Judas animals to infer the probability that a wild individual could be detected in an area of interest via Judas surveillance. We illustrated the method by using data from a feral goat eradication program on Isla Santiago, Galápagos, and a feral pig eradication program on Santa Cruz Island, California. Association probabilities declined as the proximity between individual areas of use of a Judas pair decreased. Unconditional probabilities of detection within individual areas of use averaged 0.09 per month for feral pigs and 0.11 per month for feral goats. Probabilities that eradication had been achieved, given no detections of wild conspecifics, and an uninformative prior probability of eradication were 0.79 (90% CI 0.22–0.99) for feral goats and 0.87 (90% CI 0.44–1.0) for feral pigs. We envisage several additions to the analyses used that could improve estimates of Judas detection probability. Analyses such as these can help managers increase the efficacy of eradication efforts, leading to more effective effects to restore native biodiversity. 相似文献
49.
Angus H. H. Macdonald Eugenia M. Sampayo Tyrone Ridgway Michael H. Schleyer 《Marine Biology》2008,154(2):209-217
Studies on latitudinal gradients in Symbiodinium diversity on scleractinian corals are largely restricted to warm-water low latitude locations, and it appears that there
is a shift in symbiont distributions with increasing latitude. The Symbiodinium assemblages of high latitude coral communities have largely been undocumented despite occupying an important transitional
zone between tropical and temperate regions. Using a combination of the internal transcribed spacer region 2 (ITS2) and denaturing
gradient gel electrophoresis (DGGE), we assessed the cladal and subcladal variability of Symbiodinium in the widely distributed species Stylophora pistillata along a latitudinal transect in southeast African waters which extended into high latitude locations. All colonies examined
belonged to clade C. Six unique ITS2-DGGE banding profiles (designated Cspa to Cspf) were observed, which showed a latitudinal distribution from north to south, most likely a result of a gradient in water
temperature and irradiance driven by riverine input in the southern regions. Sequence analysis revealed that all sequences
except one did not match previously identified clade C sub-types, probably due to the lack of regional information in the
Western Indian Ocean when compared to the Caribbean and Pacific. This study further supports the applicability of ITS2-DGGE
in studies on Symbiodinium diversity, and highlights that potentially ecologically informative biogeographic patterns may be overlooked when only cladal
designations are employed. 相似文献
50.
R. W. Macdonald S. Carter Schofield P. R. Slawson 《Water, Air, & Soil Pollution: Focus》2002,2(5-6):541-554
The aerodynamic behaviour of large urbanagglomerations must be represented in increasingly greaterdetail, as large-scale numerical weather prediction and airpollution dispersion models are refined. The present studyprovides detailed measurements of the flow field in regulararrays of obstacles to obtain representative data on meanflow and turbulence statistics in urban-type areas. Obstacle arrays consisting of simple cubes and flat plateroughness commonly used in boundary layer simulations wereplaced in a simulated atmospheric boundary layer flow in ahydraulic flume. The scale factor was about 1:200 based onthe obstacle height (50 mm). The results show noappreciable `constant stress' region in the internalboundary layer above the buildings, since in any finite-length test array the boundary layer is always developing.However, if the RMS turbulence components are scaled by thelocal values of the shear stress, then there seems to be auniversal scaling, with u/u* = 2.1,v/u* = 1.65 and w/u* = 1.2. This greatly simplifies the parameterization of the first orderturbulence statistics in obstacle arrays. It was alsoobserved during the experiments that, compared to results inthe cube arrays, the turbulence kinetic energy and theReynolds stresses were almost doubled in the flat plateroughness arrays. 相似文献