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The peregrine falcon (Falco peregrinus) population in southern Scandinavia was almost extinct in the 1970’s. A successful reintroduction project was launched in
1974, using captive breeding birds of northern and southern Scandinavian, Finnish and Scottish origin. We examined the genetic
structure in the pre-bottleneck population using eleven microsatellite markers and compared the data with the previously genotyped
captive breeding population and contemporary wild population. Museum specimens between 53 and 130 years old were analyzed.
Despite an apparent loss of historical genetic diversity, the contemporary population shows a relatively high level of genetic
variation. Considerable gene introgression from captive breeding stock used to repopulate the former range of southern Scandinavian
peregrines may have altered the genetic composition of this population. Both the historical and contemporary northern and
southern Scandinavian populations are genetically differentiated. The reintroduction project implemented in the region and
the use of non-native genetic stock likely prevented the southern Scandinavian population from extinction and thus helped
maintain the level of genetic diversity and prevent inbreeding depression. The population is rapidly increasing in numbers
and range and shows no indication of reduced fitness or adaptive capabilities in the wake of the severe bottleneck and the
reintroduction. 相似文献
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Using the movement patterns of reintroduced animals to improve reintroduction success 总被引:1,自引:0,他引:1
Despite their importance to conservation, reintroductions are still a risky endeavor and tend to fail, highlighting the need for more efficient post-release monitoring techniques. Reintroduced animals are released into unfamiliar novel environ ments and must explore their surroundings to gain knowledge in order to survive. According to theory, knowledge gain should be followed by subsequent changes to the animal's movement behavior, making movement behavior an excellent indicator of reintroduction progress. We aim to conceptually describe a logical process that will enable the inclusion of behavior (in particular, movement behavior) in management decision-making post-reintroductions, and to do so, we provide four basic components that a manager should look for in the behaviors of released animals. The suggested components are release-site fidelity, recurring locations, proximity to other individuals, and individual variation in movement behavior. These components are by no means the only possible ones available to a manager, but they provide an efficient tool to understanding animals' decision-making based on ecological theory; namely, the exploration-exploitation trade-off that released animals go through, and which underlies their behavior. We demonstrate our conceptual approach using data from two ungulate species reintroduced in Israel: the Persian fallow deer Dama mesopotamica and the Arabian oryx Oryx leucoryx [Current Zoology 60 (4): 515-526, 2014] . 相似文献
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The climate and biodiversity crises are inextricably linked and curbing both requires large-scale ecosystem restoration to be put into practice. In this context, trophic rewilding, which focusses on the restoration of megafauna and their ecological roles, remains a particularly major challenge. Many landscapes across the globe currently have low densities of megafauna or have lost these species altogether. Although some megafauna species have recovered in some places, through both passive and active rewilding, they are often confined to small areas. There is an increasing recognition that protected areas alone may not suffice to retain and recover high trophic complexity over large spatial extents in most of the world. This raises a clear need to scale up rewilding initiatives. Here, we discuss major challenges and potential solutions for such a scaling up of trophic rewilding, including land availability, supportive policies, the supply of animals for translocations and reintroductions, and funding. We illustrate these challenges and opportunities for two cases, the steppes of Kazakhstan and the Mediterranean rangelands. We highlight that ongoing structural change and agricultural abandonment offers opportunities for trophic rewilding in different world regions. Making use of these opportunities would require mainstreaming land-use planning that supports rewilding regardless of the current protection status of landscapes, and a reorientation of subsidies for agricultural activities in marginal lands to supporting restoration efforts. The supply of animals for reintroduction and population reinforcement projects represents another key challenge. This could be supported through a transition from farming to wildlife ranching, combined with ambitious breeding programs for keystone megafauna. Upscaling restoration efforts has recently been agreed upon as a global conservation target, and we here highlight the challenges and opportunities for restoring megafauna and their key role in ecosystems. 相似文献
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Outcome prediction is important for conservation; however, analysis may be hampered by specialist resource deficiencies. Mental modelling techniques offer a potential solution, drawing on accessible sources of knowledge held informally by local stakeholders. Mental models show linked social and ecological variables from the perspectives of community members, whose insights may otherwise be neglected. Currently, an important weakness in conservation mental modelling is inadequate attention paid to real-time model predictive validity. To address this knowledge gap, baseline mental model predictions concerning Beaver (Castor fiber) reintroduction in Southwest England were followed up at three years. Participants were invited to submit outcome observations for concept variables identified in their original models, blind to inferences based on model dynamic analysis, so that the two sets of data could be compared. Individual concept values and models were found to show weak and highly inconsistent predictive validity, however, multi-stakeholder aggregated mental models showed consistently strong predictive performance. This finding was enhanced by setting tighter thresholds for inclusion of individual model items in aggregation procedures. Threshold effects can be interpreted as a reflection of greater agreement: tighter thresholds retain more highly shared model components. It is proposed that enhanced real-time predictive validity for aggregated models is explained by a ‘wisdom of the crowd’ statistical effect, analogous to well-recognised crowd judgement effects observed in relation to much simpler questions. The findings show the scope for stakeholder mental modelling methods as an investigative tool, to supplement more conventional ecosystem assessments in predicting data-poor conservation outcomes. 相似文献
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Population viability and metapopulation theory and models are heuristic tools that can be used to plan restorations and assess their success. Using examples from South Florida, USA, we review background information and ongoing reintroduction experiments with the federally endangered coastal perennial vine, beach jacquemontia, Jacquemontia reclinata (Convolvulaceae). All known wild populations are declining in isolated habitat fragments varying in size, occupied area, and degree of isolation. Eleven reintroduction sites ranging in size from 422 to 4800 m2 within the extant species’ range have been identified that have characteristics suitable for J. reclinata introductions and have land managers amenable to restoration efforts. Previous RAPD analysis indicated that genetic diversity of natural populations was positively correlated with population size; the two largest populations had the highest genetic diversity and the smallest populations had relatively low genetic diversity. Despite habitat fragmentation and large distances between some populations, migration rates were very high among populations (m=4.05). Experimental crosses indicated the species has a mixed mating system. From 2001 to 2005, we have introduced 935 J. reclinata in seven experiments in five locations using plants propagated ex situ at Fairchild Tropical Botanic Garden. Reintroductions have dramatically increased the number of plants in the wild by 72%. Survival from the time of transplant to 2005 ranged from 2% to 97%, was not significantly correlated with metapopulation parameters, such as, founding population size, patch size, or connectivity to extant populations. Reintroduced plants are contributing seed and pollen to the wild populations, but no recruited seedlings have yet been observed. Although it may take decades before we can consider the reintroduced populations to be self-sustainable, we argue that planning restorations for rare species based on predictions from ecological theory is advisable to allow a higher probability of success. 相似文献
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