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71.
S. T. Garnett S. H. M. Butchart G. B. Baker E. Bayraktarov K. L. Buchanan A. A. Burbidge A. L. M. Chauvenet L. Christidis G. Ehmke M. Grace D. G. Hoccom S. M. Legge I. Leiper D. B. Lindenmayer R. H. Loyn M. Maron P. McDonald P. Menkhorst H. P. Possingham J. Radford A. E. Reside D. M. Watson J. E. M. Watson B. Wintle J. C. Z. Woinarski H. M. Geyle 《Conservation biology》2019,33(2):456-468
Although evidence-based approaches have become commonplace for determining the success of conservation measures for the management of threatened taxa, there are no standard metrics for assessing progress in research or management. We developed 5 metrics to meet this need for threatened taxa and to quantify the need for further action and effective alleviation of threats. These metrics (research need, research achievement, management need, management achievement, and percent threat reduction) can be aggregated to examine trends for an individual taxon or for threats across multiple taxa. We tested the utility of these metrics by applying them to Australian threatened birds, which appears to be the first time that progress in research and management of threats has been assessed for all threatened taxa in a faunal group at a continental scale. Some research has been conducted on nearly three-quarters of known threats to taxa, and there is a clear understanding of how to alleviate nearly half of the threats with the highest impact. Some management has been attempted on nearly half the threats. Management outcomes ranged from successful trials to complete mitigation of the threat, including for one-third of high-impact threats. Progress in both research and management tended to be greater for taxa that were monitored or occurred on oceanic islands. Predation by cats had the highest potential threat score. However, there has been some success reducing the impact of cat predation, so climate change (particularly drought), now poses the greatest threat to Australian threatened birds. Our results demonstrate the potential for the proposed metrics to encapsulate the major trends in research and management of both threats and threatened taxa and provide a basis for international comparisons of evidence-based conservation science. 相似文献
72.
NICK M. HADDAD†† BRIAN HUDGENS† CHRIS DAMIANI‡ KEVIN GROSS§ DANIEL KUEFLER KEN POLLOCK 《Conservation biology》2008,22(4):929-940
Abstract: Determining population viability of rare insects depends on precise, unbiased estimates of population size and other demographic parameters. We used data on the endangered St. Francis' satyr butterfly (Neonympha mitchellii francisci) to evaluate 2 approaches (mark–recapture and transect counts) for population analysis of rare butterflies. Mark–recapture analysis provided by far the greatest amount of demographic information, including estimates (and standard errors) of population size, detection, survival, and recruitment probabilities. Mark–recapture analysis can also be used to estimate dispersal and temporal variation in rates, although we did not do this here. Models of seasonal flight phenologies derived from transect counts (Insect Count Analyzer) provided an index of population size and estimates of survival and statistical uncertainty. Pollard–Yates population indices derived from transect counts did not provide estimates of demographic parameters. This index may be highly biased if detection and survival probabilities vary spatially and temporally. In terms of statistical performance, mark–recapture and Pollard–Yates indices were least variable. Mark–recapture estimates were less likely to fail than Insect Count Analyzer, but mark–recapture estimates became less precise as sampling intensity decreased. In general, count‐based approaches are less costly and less likely to cause harm to rare insects than mark–recapture. The optimal monitoring approach must reconcile these trade‐offs. Thus, mark–recapture should be favored when demographic estimates are needed, when financial resources enable frequent sampling, and when marking does not harm the insect populations. The optimal sampling strategy may use 2 sampling methods together in 1 overall sampling plan: limited mark–recapture sampling to estimate survival and detection probabilities and frequent but less expensive transect counts. 相似文献
73.
Abstract: Some conservationists argue for a focused effort to protect the most critically endangered species, and others suggest a large‐scale endeavor to safeguard common species across large areas. Similar arguments are applicable to the distribution of scientific effort among species. Should conservation scientists focus research efforts on threatened species, common species, or do all species deserve equal attention? We assessed the scientific equity among 1909 mammals, birds, reptiles, and amphibians of southern Africa by relating the number of papers written about each species to their status on the International Union for Conservation of Nature Red List. Threatened large mammals and reptiles had more papers written about them than their nonthreatened counterparts, whereas threatened small mammals and amphibians received less attention than nonthreatened species. Threatened birds received an intermediate amount of attention in the scientific literature. Thus, threat status appears to drive scientific effort among some animal groups, whereas other factors (e.g., pest management and commercial interest) appear to dictate scientific investment in particular species of other groups. Furthermore, the scientific investment per species differed greatly between groups—the mean number of papers per threatened large mammal eclipsed that of threatened reptiles, birds, small mammals, and amphibians by 2.6‐, 15‐, 216‐, and more than 500‐fold, respectively. Thus, in the eyes of science, all species are not created equal. A few species commanded a great proportion of scientific attention, whereas for many species information that might inform conservation is virtually nonexistent. 相似文献
74.
John G. Sidle 《Environmental management》1987,11(4):429-437
The critical habitat provision of the US Endangered Species Act was believed by many to be a key feature of the Act. It was believed that this provision would benefit federally listed endangered and threatened species. However, only 23% of the listed species in the United States have their critical habitats designated. The current trend is to forego critical habitat designation because the federal government believes that the Endangered Species Act can protect most listed species without resort to the critical habitat provision. Required publication of critical habitat locations in theFederal Register may draw vandals and collectors to rare species. In other cases, existing habitat protection already provides adequate protection for species. In a few instances critical habitat changes over time and is difficult to delineate. Lastly, designating critical habitat is time consuming, delays species listing, and is controversial, detracting from the positive image of the Endangered Species Act. 相似文献
75.
Angehr GR Siegel J Aucca C Christian DG Pequeño T 《Environmental monitoring and assessment》2002,76(1):69-87
We developed an assessment and monitoring plan for birds in connection with the exploration and potential development of a large natural gas field in the Lower Urubamba drainage of Peru, a project of Shell Prospecting and Development Peru (SPDP). Our objectives were to: (1) inventory the birds in the area, including information on habitat use and abundance, and (2) devise long-term monitoring protocols for birds. We sampled birds through a combination of visual and auditory surveys and mist-netting at 4 well sites and 3 sites along the Urubamba and Camisea rivers. We recorded 420 speciesduring 135 days of field work. We consider the highest prioritiesfor a future monitoring program to be: (1) establish whether edge effects are occurring at well sites, along roads and alongthe planned pipeline route and determine the significance and extent of these effects and (2) assess the impact of increased human access to the area on game and other exploited species. The remoteness of the area, its rugged terrain and dense vegetation and the lack of trained personnel limit the choice of survey and monitoring methods. We recommend use of mist-netting and transects for monitoring edge effects and useof transects for monitoring game and other exploited species. 相似文献
76.
Development of a Bird Integrity Index: Measuring Avian Response to Disturbance in the Blue Mountains of Oregon, USA 总被引:1,自引:0,他引:1
Bryce SA 《Environmental management》2006,38(3):470-486
The Bird Integrity Index (BII) presented here uses bird assemblage information to assess human impacts to 28 stream reaches
in the Blue Mountains of eastern Oregon. Eighty-one candidate metrics were extracted from bird survey data for testing. The
metrics represented aspects of bird taxonomic richness, tolerance or intolerance to human disturbance, dietary preferences,
foraging techniques, and nesting strategies that were expected to be positively or negatively affected by human activities
in the region. To evaluate the responsiveness of each metric, it was plotted against an index of reach and watershed disturbance
that included attributes of land use/land cover, road density, riparian cover, mining impacts, and percent area in clearcut
and partial-cut logging. Nine of the 81 candidate bird metrics remained after eliminating unresponsive and highly correlated
metrics. Individual metric scores ranged from 0 to 10, and BII scores varied between 0 and 100. BII scores varied from 78.6
for a minimally disturbed, reference stream reach to 30.4 for the most highly disturbed stream reach. The BII responded clearly
to varying riparian conditions and to the cumulative effects of disturbances, such as logging, grazing, and mining, which
are common in the mountains of eastern Oregon. This BII for eastern Oregon was compared to an earlier BII developed for the
agricultural and urban disturbance regime of the Willamette Valley in western Oregon. The BII presented here was sensitive
enough to distinguish differences in condition among stream riparian zones with disturbances that were not as obvious or irreversible
as those in the agricultural/urban conditions of western Oregon. 相似文献
77.
Ainara Corts-Avizanda Henrique M. Pereira Ellen McKee Olga Ceballos Berta Martín-Lpez 《Ambio》2022,51(4):990
AbstractIn the current Anthropocene Era, with numerous escalating challenges for biodiversity conservation, the inclusion of the social dimension into management decisions regarding wildlife and protected areas is critical to their success. By conducting 354 questionnaires in a Mediterranean protected area (the Biosphere Reserve of Bardenas Reales, Northern Spain), we aim to determine sociodemographic factors influencing knowledge levels and perceptions of species and functional groups as, emblematic and threatened. We found that hunters and animal husbandry workers knew more species than other social actors. Additionally, the perception of functional groups as threatened or emblematic differed between social actor groups, with statistically significant associations between perceptions and the characteristics of respondents. Interestingly, we found that although elusive steppe species are globally considered as endangered, these species were the least known by all social actor groups and rarely perceived as emblematic. This research is a novel approach and provides a better understanding of how perceptions can facilitate conservation decisions, particularly regarding endangered speciesGraphic abstract Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01546-6. 相似文献
78.
重庆三峡库区鸟类生物多样性研究 总被引:11,自引:2,他引:9
通过1996-1997年的调查,记录三峡工程重庆库区鸟类293种,分属17目45科,159属,比文献记录新增加33种,其中重庆市鸟类新记录9种。鸟类区系成分以东洋界为主体。国家重点保护动物29种,Ⅰ类2种,Ⅱ类27种;除红腹锦鸡种群数量较多外,其余都较稀少。从分布上看,库区东段的种类和数量比西段多;海拔1200m以上物种丰富;1200m以下为强度农耕区,种类较为贫乏,主要是一些与人为活动相关的种类。表1参9 相似文献
79.
Historical operations at the Hanford Site (Washington State, USA) have released a wide array of non-radionuclide and radionuclide contaminants into the environment. As a result, there is a need to characterize contaminant effects on site biota. Within this framework, the main purpose of our study was to evaluate radionuclide concentrations in bird tissue, obtained from the Hanford Environmental Information System (HEIS). The database was sorted by avian group (water bird vs. upland bird), radionuclide (over 20 analytes), tissue (muscle, bone, liver), location (onsite vs. offsite), and time period (1971-1990 vs. 1991-2009). Onsite median concentrations in water birds were significantly higher (Bonferroni P < 0.05) than those in onsite upland birds for Cs-137 in muscle (1971-1990) and Sr-90 in bone (1991-2009), perhaps due to behavioral, habitat, or trophic species differences. Onsite median concentrations in water birds were higher (borderline significance with Bonferroni P = 0.05) than those in offsite birds for Cs-137 in muscle (1971-1990). Onsite median concentrations in the earlier time period were significantly higher (Bonferroni P < 0.05) than those in the later time period for Co-60, Cs-137, Eu-152, and Sr-90 in water bird muscle and for Cs-137 in upland bird muscle tissue. Median concentrations of Sr-90 in bone were significantly higher (Bonferroni P < 0.05) than those in muscle for both avian groups and both locations. Over the time period, 1971-2009, onsite median internal dose was estimated for each radionuclide in water bird and upland bird tissues. However, a meaningful dose comparison between bird groups was not possible, due to a dissimilar radionuclide inventory, mismatch of time periods for input radionuclides, and lack of an external dose estimate. Despite these limitations, our results contribute toward ongoing efforts to characterize ecological risk at the Hanford Site. 相似文献
80.
Field Validation of a Conservation Network on the Eastern Shore of Maryland,USA, Using Breeding Birds as Bio-Indicators 总被引:1,自引:0,他引:1
Maryland’s Green Infrastructure (GI) is a network of large, intact natural areas (hubs), interconnected by linear swaths of
riparian or upland vegetation (corridors). The GI serves significant ecological functions and provides the bulk of the state’s
natural support system. This study examined whether the GI as mapped does, in fact, identify Maryland’s most ecologically
valuable forested lands, using forest interior dwelling birds (hereafter called “forest birds”) as bio-indicators. We conducted
bird point counts within forest both inside and outside of hubs on Maryland’s Eastern Shore. We also collected a wide variety
of habitat data. We found that both the condition of a forest and its surrounding landscape influenced the bird communities.
On average, forest bird richness was significantly higher within hubs; furthermore, almost all sites with at least five forest
bird species present were in hubs. Forest bird richness and abundance were highest in undisturbed, mature broadleaf forest
with wetlands and streams nearby. We detected a significant relationship between forest bird richness and the ecological score
of a finer-scale landscape assessment, focused on “cells” of about 0.1 ha in size. This field study also validated the Rapid
Field Assessment (RFA) protocol developed in 2001 to assess, on the ground, the relative condition of individual sites or
properties within the GI. Forest bird richness and abundance were positively correlated with the RFA community scores. Our
results underscore the importance of maintaining regional biological diversity by retaining large blocks of forest, especially
mature forest containing streams and wetlands. 相似文献