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131.
Michael J. Manfredo Jeremy T. Bruskotter Tara L. Teel David Fulton Shalom H. Schwartz Robert Arlinghaus Shigehiro Oishi Ayse K. Uskul Kent Redford Shinobu Kitayama Leeann Sullivan 《Conservation biology》2017,31(4):772-780
The hope for creating widespread change in social values has endured among conservation professionals since early calls by Aldo Leopold for a “land ethic.” However, there has been little serious attention in conservation to the fields of investigation that address values, how they are formed, and how they change. We introduce a social–ecological systems conceptual approach in which values are seen not only as motivational goals people hold but also as ideas that are deeply embedded in society's material culture, collective behaviors, traditions, and institutions. Values define and bind groups, organizations, and societies; serve an adaptive role; and are typically stable across generations. When abrupt value changes occur, they are in response to substantial alterations in the social–ecological context. Such changes build on prior value structures and do not result in complete replacement. Given this understanding of values, we conclude that deliberate efforts to orchestrate value shifts for conservation are unlikely to be effective. Instead, there is an urgent need for research on values with a multilevel and dynamic view that can inform innovative conservation strategies for working within existing value structures. New directions facilitated by a systems approach will enhance understanding of the role values play in shaping conservation challenges and improve management of the human component of conservation. 相似文献
132.
Mitigating the massive impacts of defaunation on natural ecosystems requires understanding and predicting hunting effort across the landscape. But such understanding has been hindered by the difficulty of assessing the movement patterns of hunters in thick forests and across complex terrain. We statistically tested hypotheses about the spatial distribution of hunting with circuit theory and structural equation models. We used a data set of >7000 known kill locations in Guyana and hunter movement models to test these methods. Comparing models with different resistance layers (i.e., different estimates of how terrain and land cover influence human movement speed) showed that rivers, on average, limited movement rather than serving as transport arteries. Moreover, far more kills occurred close to villages than in remote areas. This, combined with the lack of support for structural equation models that included latent terms for prey depletion driven by past overhunting, suggests that kill locations in this system tended to be driven by where hunters were currently foraging rather than by influences of historical harvest. These analyses are generalizable to a variety of ecosystems, species, and data types, providing a powerful way of enhancing maps and predictions of hunting effort across complex landscapes. 相似文献
133.
ZOE JEWELL 《Conservation biology》2013,27(3):501-508
Monitoring free‐ranging animals in their natural habitat is a keystone of ecosystem conservation and increasingly important in the context of current rates of loss of biological diversity. Data collected from individuals of endangered species inform conservation policies. Conservation professionals assume that these data are reliable—that the animals from whom data are collected are representative of the species in their physiology, ecology, and behavior and of the populations from which they are drawn. In the last few decades, there has been an enthusiastic adoption of invasive techniques for gathering ecological and conservation data. Although these can provide impressive quantities of data, and apparent insights into animal ranges and distributions, there is increasing evidence that these techniques can result in animal welfare problems, through the wide‐ranging physiological effects of acute and chronic stress and through direct or indirect injuries or compromised movement. Much less commonly, however, do conservation scientists consider the issue of how these effects may alter the behavior of individuals to the extent that the data they collect could be unreliable. The emerging literature on the immediate and longer‐term effects of capture and handling indicate it can no longer be assumed that a wild animal's survival of the process implies the safety of the procedure, that the procedure is ethical, or the scientific validity of the resulting data. I argue that conservation professionals should routinely assess study populations for negative effects of their monitoring techniques and adopt noninvasive approaches for best outcomes not only for the animals, but also for conservation science. Efecto de la Técnica de Monitoreo en la Calidad de la Ciencia de la Conservación 相似文献
134.
Abstract: Indigenous people inhabit approximately 85% of areas designated for biodiversity conservation worldwide. They also continue to struggle for recognition and preservation of cultural identities, lifestyles, and livelihoods—a struggle contingent on control and protection of traditional lands and associated natural resources (hereafter, self‐determination). Indigenous lands and the biodiversity they support are increasingly threatened because of human population growth and per capita consumption. Application of the Endangered Species Act (ESA) to tribal lands in the United States provides a rich example of the articulation between biodiversity conservation and indigenous peoples' struggle for self‐determination. We found a paradoxical relationship whereby tribal governments are simultaneously and contradictorily sovereign nations; yet their communities depend on the U.S. government for protection through the federal‐trust doctrine. The unique legal status of tribal lands, their importance for conserving federally protected species, and federal environmental regulations' failure to define applicability to tribal lands creates conflict between tribal sovereignty, self‐determination, and constitutional authority. We reviewed Secretarial Order 3206, the U.S. policy on “American Indian tribal rights, federal–tribal trust responsibilities, and the ESA,” and evaluated how it influences ESA implementation on tribal lands. We found improved biodiversity conservation and tribal self‐determination requires revision of the fiduciary relationship between the federal government and the tribes to establish clear, legal definitions regarding land rights, applicability of environmental laws, and financial responsibilities. Such actions will allow provision of adequate funding and training to tribal leaders and resource managers, government agency personnel responsible for biodiversity conservation and land management, and environmental policy makers. Increased capacity, cooperation, and knowledge transfer among tribes and conservationists will improve biodiversity conservation and indigenous self‐determination. 相似文献
135.
Abstract: Successful protection of biodiversity requires increased understanding of the ecological characteristics that predispose some species to endangerment. Theory posits that species with polymorphic or variable coloration should have larger distributions, use more diverse resources, and be less vulnerable to population declines and extinctions, compared with taxa that do not vary in color. We used information from literature on 194 species of Australian frogs to search for associations of coloration mode with ecological variables. In general, species with variable or polymorphic color patterns had larger ranges, used more habitats, were less prone to have a negative population trend, and were estimated as less vulnerable to extinction compared with nonvariable species. An association of variable coloration with lower endangerment was also evident when we controlled statistically for the effects of range size. Nonvariable coloration was not a strong predictor of endangerment, and information on several characteristics is needed to reliably identify and protect species that are prone to decline and may become threatened by extinction in the near future. Analyses based on phylogenetic‐independent contrasts did not support the hypothesis that evolutionary transitions between nonvariable and variable or polymorphic coloration have been accompanied by changes in the ecological variables we examined. Irrefutable demonstration of a role of color pattern variation in amphibian decline and in the dynamics and persistence of populations in general will require a manipulative experimental approach. 相似文献
136.
Abstract: Marine protected areas (MPAs), including no‐take marine reserves (MRs), play an important role in the conservation of marine biodiversity. We document the status of MPAs and MRs in Latin America and the Caribbean, where little has been reported on the scope of such protection. Our survey of protected area databases, published and unpublished literature, and Internet searches yielded information from 30 countries and 12 overseas territories. At present more than 700 MPAs have been established, covering more than 300,000 km2 or 1.5% of the coastal and shelf waters. We report on the status of 3 categories of protection: MPAs (limited take throughout the area), MRs (no‐take throughout the area), and mixed‐use (a limited‐take MPA that contains an MR). The majority of protected areas in Latin America and the Caribbean are MPAs, which allow some or extensive extractive activities throughout the designated area. These 571 sites cover 51,505 km2 or 0.3% of coastal and shelf waters. There are 98 MRs covering 16,862 km2 or 0.1% of the coastal and shelf waters. Mixed‐use MPAs are the fewest in number (87), but cover the largest area (236,853 km2, 1.2%). Across Latin America and the Caribbean, many biogeographic provinces are underrepresented in these protected areas. Large coastal regions remain unprotected, in particular, the southern Pacific and southern Atlantic coasts of South America. Our analysis reveals multiple opportunities to strengthen marine conservation in Latin America and the Caribbean by improving implementation, management, and enforcement of existing MPAs; adding new MPAs and MRs strategically to enhance connectivity and sustainability of existing protection; and establishing new networks of MPAs and MRs or combinations thereof to enhance protection where little currently exists. 相似文献
137.
Abstract: Anthropogenic disturbances such as fragmentation are rapidly altering biodiversity, yet a lack of attention to species traits and abundance patterns has made the results of most studies difficult to generalize. We determined traits of extinction‐prone species and present a novel strategy for classifying species according to their population‐level response to a gradient of disturbance intensity. We examined the effects of forest fragmentation on dung beetle communities in an archipelago of 33 islands recently created by flooding in Venezuela. Species richness, density, and biomass all declined sharply with decreasing island area and increasing island isolation. Species richness was highly nested, indicating that local extinctions occurred nonrandomly. The most sensitive dung beetle species appeared to require at least 85 ha of forest, more than many large vertebrates. Extinction‐prone species were either large‐bodied, forest specialists, or uncommon. These explanatory variables were unrelated, suggesting at least 3 underlying causes of extirpation. Large species showed high wing loading (body mass/wing area) and a distinct flight strategy that may increase their area requirements. Although forest specificity made most species sensitive to fragmentation, a few persistent habitat generalists dispersed across the matrix. Density functions classified species into 4 response groups on the basis of their change in density with decreasing species richness. Sensitive and persistent species both declined with increasing fragmentation intensity, but persistent species occurred on more islands, which may be due to their higher baseline densities. Compensatory species increased in abundance following the initial loss of sensitive species, but rapidly declined with increasing fragmentation. Supertramp species (widespread habitat generalists) may be poor competitors but strong dispersers; their abundance peaked following the decline of the other 3 groups. Nevertheless, even the least sensitive species were extirpated or rare on the smallest and most isolated islands. 相似文献
138.
We present a case report on a fetus with multiple malformations, diagnosed by ultrasound at 20 weeks' gestation. From the combination of intrauterine growth retardation and limb abnormalities that were observed, the most likely diagnosis was considered to be Cornelia de Lange Syndrome (CdLS). Following counselling, the mother opted to terminate the pregnancy. Chromosome analysis of cultured amniotic fluid cells showed a karyotype of 46,XX,t(3;5)(q21;p13). Postmortem examination of the baby confirmed the presence of features consistent with a diagnosis of CdLS. This case provides a report of a definitive diagnosis of Cornelia de Lange Syndrome, suspected on the basis of ultrasound imaging and confirmed by amniocentesis findings. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
139.
Rebecca Niemiec Megan S. Jones Stacy Lischka Veronica Champine 《Conservation biology》2021,35(4):1073-1085
Research suggests that encouraging motivated residents to reach out to others in their social network is an effective strategy for increasing the scale and speed of conservation action adoption. However, little is known about how to effectively encourage large numbers of residents to reach out to others about conservation causes. We examined the influence of normative and efficacy-based messaging at motivating residents to engage in and to encourage others to participate in native plant gardening in their community. To do so, we conducted a field experiment with messages on mailings and tracked native plant vouchers used. Efficacy messages tended to be more effective than normative messages at increasing residents’ willingness to reach out to others to encourage conservation action, as indicated by a several percentage point increase in native plant voucher use by residents’ friends and neighbors. Messages sometimes had different impacts on residents based on past behaviors and perceptions related to native plant gardening. Among these subgroups, efficacy and combined efficacy and norm messages most effectively encouraged individual and collective actions, as indicated by increased voucher usage. Our findings suggest that interventions that build residents’ efficacy for engaging in a conservation behavior and for reaching out to others may be a promising path forward for outreach. However, given our results were significant at a false discovery rate cutoff of 0.25 but not 0.05, more experimental trials are needed to determine the robustness of these trends. 相似文献
140.
Pollinator welfare is a recognized research and policy target, and urban greenspaces have been identified as important habitats. Yet, landscape-scale habitat fragmentation and greenspace management practices may limit a city's conservation potential. We examined how landscape configuration, composition, and local patch quality influenced insect nesting success across inner-city Cleveland, Ohio (U.S.A.), a postindustrial legacy city containing a high abundance of vacant land (over 1600 ha). Here, 40 vacant lots were assigned 1 of 5 habitat treatments (T1, vacant lot; T2, grass lawn; T3, flowering lawn; T4, grass prairie; and T5, flowering prairie), and we evaluated how seeded vegetation, greenspace size, and landscape connectivity influenced cavity-nesting bee and wasp reproduction. Native bee and wasp larvae were more abundant in landscapes that contained a large patch (i.e., >6 ha) of contiguous greenspace, in habitats with low plant biomass, and in vacant lots seeded with a native wildflower seed mix or with fine-fescue grass, suggesting that fitness was influenced by urban landscape features and habitat management. Our results can guide urban planning by demonstrating that actions that maintain large contiguous greenspace in the landscape and establish native plants would support the conservation of bees and wasps. Moreover, our study highlights that the world's estimated 350 legacy cities are promising urban conservation targets due to their high abundance of vacant greenspace that could accommodate taxa's habitat needs in urban areas. 相似文献