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271.
Major shifts in Amazon wildlife populations from recent intensification of floods and drought
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Richard Bodmer Pedro Mayor Miguel Antunez Kimberlyn Chota Tula Fang Pablo Puertas Marlini Pittet Maire Kirkland Mike Walkey Claudia Rios Pedro Perez‐Peña Peter Henderson William Bodmer Andy Bicerra Joseph Zegarra Emma Docherty 《Conservation biology》2018,32(2):333-344
In the western Amazon Basin, recent intensification of river‐level cycles has increased flooding during the wet seasons and decreased precipitation during the dry season. Greater than normal floods occurred in 2009 and in all years from 2011 to 2015 during high‐water seasons, and a drought occurred during the 2010 low‐water season. During these years, we surveyed populations of terrestrial, arboreal, and aquatic wildlife in a seasonally flooded Amazonian forest in the Loreto region of Peru (99,780 km2) to study the effects of intensification of natural climatic fluctuations on wildlife populations and in turn effects on resource use by local people. Shifts in fish and terrestrial mammal populations occurred during consecutive years of high floods and the drought of 2010. As floods intensified, terrestrial mammal populations decreased by 95%. Fish, waterfowl, and otter (Pteronura brasiliensis) abundances increased during years of intensive floods, whereas river dolphin and caiman populations had stable abundances. Arboreal species, including, macaws, game birds, primates, felids, and other arboreal mammals had stable populations and were not affected directly by high floods. The drought of 2010 had the opposite effect: fish, waterfowl, and dolphin populations decreased, and populations of terrestrial and arboreal species remained stable. Ungulates and large rodents are important sources of food and income for local people, and large declines in these animals has shifted resource use of people living in the flooded forests away from hunting to a greater reliance on fish. 相似文献
272.
Traps and transformations influencing the financial viability of tourism on private‐land conservation areas
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The ability of private conservation organizations to remain financially viable is a key factor influencing their effectiveness. One‐third of financially motivated private‐land conservation areas (PLCAs) surveyed in South Africa are unprofitable, raising questions about landowners’ abilities to effectively adapt their business models to the socioeconomic environment. In any complex system, options for later adaptation can be constrained by starting conditions (path dependence). We tested 3 hypothesized drivers of path dependence in PLCA ecotourism and hunting business models: (H1) the initial size of a PLCA limits the number of mammalian game and thereby predators that can be sustained; (H2) initial investments in infrastructure limit the ability to introduce predators; and (H3) rainfall limits game and predator abundance. We further assessed how managing for financial stability (optimized game stocking) or ecological sustainability (allowing game to fluctuate with environmental conditions) influenced the ability to overcome path dependence. A mechanistic PLCA model based on simple ecological and financial rules was run for different initial conditions and management strategies, simulating landowner options for adapting their business model annually. Despite attempts by simulated landowners to increase profits, adopted business models after 13 years were differentiated by initial land and infrastructural assets, supporting H1 and H2. A conservation organization's initial assets can cause it to become locked into a financially vulnerable business model. In our 50‐year simulation, path dependence was overcome by fewer of the landowners who facilitated natural ecological variability than those who maintained constant hunting rates and predator numbers, but the latter experienced unsustainably high game densities in low rainfall years. Management for natural variability supported long‐term ecological sustainability but not shorter term socioeconomic sustainability for PLCAs. Our findings highlight trade‐offs between ecological and economic sustainability and suggest a role for governmental support of the private conservation industry. 相似文献
273.
Alexander Braczkowski Matthew H. Holden Christopher O'Bryan Chi‐Yeung Choi Xiaojing Gan Nicholas Beesley Yufang Gao James Allan Peter Tyrrell Daniel Stiles Peadar Brehony Revocatus Meney Henry Brink Nao Takashina Ming‐Ching Lin Hsien‐Yung Lin Niki Rust Severino G. Salmo III James E.M. Watson Paula Kahumbu Martine Maron Hugh P. Possingham Duan Biggs 《Conservation biology》2018,32(4):765-773
Recent increases in ivory poaching have depressed African elephant populations. Successful enforcement has led to ivory stockpiling. Stockpile destruction is becoming increasingly popular, and most destruction has occurred in the last 5 years. Ivory destruction is intended to send a strong message against ivory consumption, both in promoting a taboo on ivory use and catalyzing policy change. However, there has been no effort to establish the distribution and extent of media reporting on ivory destruction events globally. We analyzed media coverage of the largest ivory destruction event in history (Kenya, 30 April 2016) across 11 nation states connected to ivory trade. We used an online‐media crawling tool to search online media outlets and subjected 5 of the largest print newspapers (by circulation) in 5 nations of interest to content analysis. Most online news on the ivory burn came from the United States (81% of 1944 articles), whereas most of the print news articles came from Kenya (61% of 157 articles). Eighty‐six to 97% of all online articles reported the burn as a positive conservation action, whereas 4–50% discussed ivory burning as having a negative impact on elephant conservation. Most articles discussed law enforcement and trade bans as effective for elephant conservation. There was more relative search interest globally in the 2016 Kenyan ivory burn than any other burn in 5 years. Ours is the first attempt to track the reach of media coverage relative to an ivory burn and provides a case study in tracking the effects of a conservation‐marketing event. 相似文献
274.
Maarten De Brauwer Jean‐Paul A. Hobbs Rohani Ambo‐Rappe Jamaluddin Jompa Euan S. Harvey Jennifer L. McIlwain 《Conservation biology》2018,32(3):706-715
As ecosystems come under increasing anthropogenic pressure, rare species face the highest risk of extinction. Paradoxically, data necessary to evaluate the conservation status of rare species are often lacking because of the challenges of detecting species with low abundance. One group of fishes subject to this undersampling bias are those with cryptic body patterns. Twenty‐one percent of cryptic fish species assessed for their extinction risk (International Union for Conservation of Nature [IUCN]) are data deficient. We developed a nondestructive method for surveying cryptically patterned marine fishes based on the presence of biofluorescence (underwater biofluorescence census, UBC). Blue LED torches were used to investigate how widespread biofluorescence was in cryptic reef fishes in the Coral Triangle region. The effectiveness of UBC to generate abundance data was tested on a data‐deficient pygmy seahorse species (Hippocampus bargibanti) and compared with data obtained from standard underwater visual census (UVC) surveys. We recorded 95 reef fish species displaying biofluorescence, 73 of which had not been previously described as biofluorescent. Of those fish with cryptic patterns, 87% were biofluorescent compared with 9% for noncryptic fishes. The probability of species displaying biofluorescence was 70.9 times greater for cryptic species than for noncryptic species. Almost twice the number of H. bargibanti was counted using the UBC compared with UVC. For 2 triplefin species (Ucla xenogrammus, Enneapterygius tutuilae), the abundance detected with UBC was triple that detected with UVC. The UBC method was effective at finding cryptic species that would otherwise be difficult to detect and thus will reduce interobserver variability inherent to UVC surveys. Biofluorescence is ubiquitous in cryptic fishes, making this method applicable across a wide range of species. Data collected using UBC could be used with multiple IUCN criteria to assess the extinction risk of cryptic species. Adopting this technique will enhance researchers’ ability to survey cryptic species and facilitate management and conservation of cryptic marine species. 相似文献
275.
Effects of temperature and precipitation on grassland bird nesting success as mediated by patch size
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Grassland birds are declining faster than any other bird guild across North America. Shrinking ranges and population declines are attributed to widespread habitat loss and increasingly fragmented landscapes of agriculture and other land uses that are misaligned with grassland bird conservation. Concurrent with habitat loss and degradation, temperate grasslands have been disproportionally affected by climate change relative to most other terrestrial biomes. Distributions of grassland birds often correlate with gradients in climate, but few researchers have explored the consequences of weather on the demography of grassland birds inhabiting a range of grassland fragments. To do so, we modeled the effects of temperature and precipitation on nesting success rates of 12 grassland bird species inhabiting a range of grassland patches across North America (21,000 nests from 81 individual studies). Higher amounts of precipitation in the preceding year were associated with higher nesting success, but wetter conditions during the active breeding season reduced nesting success. Extremely cold or hot conditions during the early breeding season were associated with lower rates of nesting success. The direct and indirect influence of temperature and precipitation on nesting success was moderated by grassland patch size. The positive effects of precipitation in the preceding year on nesting success were strongest in relatively small grassland patches and had little effect in large patches. Conversely, warm temperatures reduced nesting success in small grassland patches but increased nesting success in large patches. Mechanisms underlying these differences may be patch‐size‐induced variation in microclimates and predator activity. Although the exact cause is unclear, large grassland patches, the most common metric of grassland conservation, appears to moderate the effects of weather on grassland‐bird demography and could be an effective component of climate‐change adaptation. 相似文献
276.
New global initiatives to restore forest landscapes present an unparalleled opportunity to reverse deforestation and forest degradation. Participatory monitoring could play a crucial role in providing accountability, generating local buy in, and catalyzing learning in monitoring systems that need scalability and adaptability to a range of local sites. We synthesized current knowledge from literature searches and interviews to provide lessons for the development of a scalable, multisite participatory monitoring system. Studies show that local people can collect accurate data on forest change, drivers of change, threats to reforestation, and biophysical and socioeconomic impacts that remote sensing cannot. They can do this at one‐third the cost of professionals. Successful participatory monitoring systems collect information on a few simple indicators, respond to local priorities, provide appropriate incentives for participation, and catalyze learning and decision making based on frequent analyses and multilevel interactions with other stakeholders. Participatory monitoring could provide a framework for linking global, national, and local needs, aspirations, and capacities for forest restoration. 相似文献
277.
采用全尺寸实验对夏季大空间内火灾机械排烟的效率进行了研究.实验过程中主要测量了火源功率和大空间内的烟气温度两个参数.通过分析大空间内烟气温度的分布规律,得到了机械排烟控制下不同火源功率的大空间内稳定的烟气层高度.根据Heskestad羽流模型计算了烟气生成速率,与机械排烟速率比较得到了夏季大空间内火灾机械排烟的效率.实验结果表明,在夏季大空间中,当火源功率不是很大时,大空间内外的温差使得外界补充进来的空气和火灾生成的烟气更加容易发生掺混,导致机械排烟的效率大大降低;按照规范规定的6次换气率进行排烟,在实验的300~1 000 kW的火源功率范围内,夏季大空间内火灾机械排烟的效率约为30%.火源功率的增大,在一定程度上削弱了空气与烟气的掺混,机械排烟的效率略有提高,但是提高的效果并不是很明显. 相似文献
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280.
The least‐cost biodiversity impact mitigation hierarchy with a focus on marine fisheries and bycatch issues
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Least‐cost implementation of the mitigation hierarchy of impacts on biodiversity minimizes the cost of a given level of biodiversity conservation, at project or ecosystem levels, and requires minimizing costs across and within hierarchy steps. Incentive‐based policy instruments that price biodiversity to alter producer and consumer behavior and decision making are generally the most effective way to achieve least‐cost implementation across and within the different hierarchy steps and across all producers and conservation channels. Nonetheless, there are circumstances that favor direct regulation or intrinsic motivation. Conservatory offsets, introduced within the conservatory first three steps of the mitigation hierarchy, rather than the fourth step to compensate the residual, provide an additional incentive‐based policy instrument. The least‐cost mitigation hierarchy framework, induced through incentive‐based policy instruments, including conservatory offsets, mitigates fisheries bycatch consistent with given targets, the Law of the Sea, and the Convention on Biological Diversity. 相似文献