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Millions of children visit zoos every year with parents or schools to encounter wildlife firsthand. Public conservation education is a requirement for membership in professional zoo associations. However, in recent years zoos have been criticized for failing to educate the public on conservation issues and related biological concepts, such as animal adaptation to habitats. I used matched pre‐ and postvisit mixed methods questionnaires to investigate the educational value of zoo visits for children aged 7–15 years. The questionnaires gathered qualitative data from these individuals, including zoo‐related thoughts and an annotated drawing of a habitat. A content analysis of these qualitative data produced the quantitative data reported in this article. I evaluated the relative learning outcomes of educator‐guided and unguided zoo visits at London Zoo, both in terms of learning about conservation biology (measured by annotated drawings) and changing attitudes toward wildlife conservation (measured using thought‐listing data). Forty‐one percent of educator‐guided visits and 34% of unguided visits resulted in conservation biology‐related learning. Negative changes in children's understanding of animals and their habitats were more prevalent in unguided zoo visits. Overall, my results show the potential educational value of visiting zoos for children. However, they also suggest that zoos’ standard unguided interpretive materials are insufficient for achieving the best outcomes for visiting children. These results support a theoretical model of conservation biology learning that frames conservation educators as toolmakers who develop conceptual resources to enhance children's understanding of science. Evaluación del Aprendizaje de Biología de la Conservación por Niños en el Zoológico Jensen  相似文献   
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Abstract: The majority of bird extinctions since 1800 have occurred on islands, and non‐native predators have been the greatest threat to the persistence of island birds. Island endemic species often lack life‐history traits and behaviors that reduce the probability of predation and they can become evolutionarily trapped if they are unable to adapt, but few studies have examined the ability of island species to respond to novel predators. The greatest threat to the persistence of the Oahu Elepaio (Chasiempis ibidis), an endangered Hawaiian forest bird, is nest predation by non‐native black rats (Rattus rattus). I examined whether Oahu Elepaio nest placement has changed at the individual and population levels in response to rat predation by measuring nest height and determining whether each nest produced offspring from 1996 to 2011. Average height of Oahu Elepaio nests increased 50% over this 16‐year period, from 7.9 m (SE 1.7) to 12.0 m (SE 1.1). There was no net change in height of sequential nests made by individual birds, which means individual elepaios have not learned to place nests higher. Nests ≤3 m off the ground produced offspring less often, and the proportion of such nests declined over time, which suggests that nest‐building behavior has evolved through natural selection by predation. Nest success increased over time, which may increase the probability of long‐term persistence of the species. Rat control may facilitate the evolution of nesting height by slowing the rate of population decline and providing time for this adaptive response to spread through the population.  相似文献   
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Multistakeholder collaboration in the environmental realm has been increasing steadily over the past decade. This trend is responding to several stimuli, including dissatisfaction with current regulatory regimes, a liberal economic climate emphasizing global competitiveness and short-term returns, and the growing roles of the business and nongovernmental organization sectors in the environmental policy arena. This paper grows out of ethnographic research conducted between 1994 and 1998 with four environmental partnerships in Europe and the United States. The research found all of these partnerships to be marked by practices of conflict minimization and diffusion. Drawing upon illustrative data from one of these case studies, a European Union level initiative aimed at enabling sustainable development in Europe, the paper asks why this was the case, especially given the diverse political and economic interests at stake and the history of contentious relations between the sectors in other venues. Employing a theoretical perspective highlighting the sociohistoric factors involved in these processes, the paper suggests that this proclivity toward nonconfrontational behavior stems in part from two sources: a prominent cultural model that conceptualizes the partnership process as fundamentally nonconflictual in nature, and the promotion of the discourse of ecological modernization over other competing discourses. The paper explores some of the implications of this finding and concludes that environmental partnerships characterized by such nonconfrontational practices risk inadvertently encouraging the delegitimization of conflictual approaches to environmental action and engendering a retreat from radical thinking and innovative environmental solutions.  相似文献   
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Two population-based surveys of South Dade County, Florida, were conducted after Hurricane Andrew to compare hurricane-related symptoms of mental distress and describe the impact of mental health outreach teams. Households were selected by three-stage cluster sampling and findings from the two surveys, 13 months apart, were compared. Response rates were 75 per cent and 84 per cent. The prevalence of symptoms of mental distress decreased over time. However, in the households contacted by the teams (25 per cent of sample), the prevalence of symptoms (50 per cent) did not differ from households not contacted (43 per cent). Households contacted by teams that reported symptoms were just as likely to have been referred for help by the teams (72 per cent) as those without symptoms (68 per cent). Households reporting symptoms were equally likely to get counselling regardless of whether the teams visited. Mental health teams had no significant impact on mental health symptoms or the use of mental health services. Alternative approaches to mental health outreach teams need to be explored.  相似文献   
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Anthropogenic carbon dioxide balancing can be evaluated by counting the amount of emissions and the sinks that absorb and release carbon. Local level planning can affect the emission-sinks balance. However when trying to meet international goals, it seems that local government mainly considers emission reduction and not sink losses. This paper investigates the implications of using carbon dioxide emissions and forest ecosystems as sinks in Swedish municipal planning. The results demonstrate how emission reduction can be offset by the losses in sinks derived by land use and transportation planning. This moves local government further away from achieving the national emission reduction goal. The results also show a potential for carbon trading between municipalities.  相似文献   
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Abstract: Many of the skills and resources associated with botanic gardens and arboreta, including plant taxonomy, horticulture, and seed bank management, are fundamental to ecological restoration efforts, yet few of the world's botanic gardens are involved in the science or practice of restoration. Thus, we examined the potential role of botanic gardens in these emerging fields. We believe a reorientation of certain existing institutional strengths, such as plant‐based research and knowledge transfer, would enable many more botanic gardens worldwide to provide effective science‐based support to restoration efforts. We recommend botanic gardens widen research to include ecosystems as well as species, increase involvement in practical restoration projects and training practitioners, and serve as information hubs for data archiving and exchange.  相似文献   
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Abstract: Since the late 1980s, Brazilian free‐tailed bats (Tadarida brasiliensis) have increasingly used bridges as roosts in the southern United States. We examined differences in blood cortisol levels, body condition, and parasite load, as measures of physiological stress in bats roosting in bridges and bats roosting in caves. We collected data during three periods, coinciding with female phases of reproduction. For all measures, bats were captured during the nightly emergence from the roost and immediately sampled. Cortisol levels were significantly higher during pregnancy and lactation and in individuals with lower body‐condition scores (length of forearm to mass ratio) and significantly higher in bats roosting in caves than in those roosting in bridges. Thus, we concluded that individuals of this species that roost in bridges are not chronically stressed and seem to be unaffected by human activities present at bridges. This is a rare documented instance where a human‐dominated environment does not appear to be adversely affecting the physiological health of a free‐ranging animal.  相似文献   
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