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191.
Meeghan?E.?GrayEmail author Elissa?Z.?Cameron Mary?M.?Peacock David?S.?Thain Veronica?S.?Kirchoff 《Behavioral ecology and sociobiology》2012,66(4):529-537
A growing number of studies conducted on diverse taxa have shown that extra-pair/group paternity is higher than what would
be predicted from behavioral observations alone. While it may be beneficial for females to mate with multiple males, this
often results in offspring not sired by the behavioral father, which could influence offspring survival, especially in social
mammals. Feral horses (Equus caballus) maintain stable social relationships over several years, usually with one stallion defending a harem band of unrelated mares
against other males. Sneak copulations by subordinate males have been observed and mares sometimes change bands, both of which
can result in foals sired by males other than the dominant band stallion. We measured female fidelity in free-ranging feral
horses in 23 bands, with 51 foals over four foaling seasons and tested offspring paternity against parental behaviors. We
used 12 polymorphic microsatellite loci and the program CERVUS 2.0 to determine and exclude potential sires. The majority
of mares remained in the band with the sire of their foal resulting in most foals being sired by the band stallion. Most foals
that were not sired by the band stallion were born in the year after a round-up and we could not determine if they were the
result of band changing or sneak copulations. Foals born into a band without their sire had lower survival rates and mothers
were significantly more protective of foals not sired by the band stallion. These findings suggest that band stability increases
the reproductive success of mares and support the importance of infanticide risk in equid social structure. 相似文献
192.
Rodhouse TJ Ormsbee PC Irvine KM Vierling LA Szewczak JM Vierling KT 《Ecological applications》2012,22(4):1098-1113
Bats face unprecedented threats from habitat loss, climate change, disease, and wind power development, and populations of many species are in decline. A better ability to quantify bat population status and trend is urgently needed in order to develop effective conservation strategies. We used a Bayesian autoregressive approach to develop dynamic distribution models for Myotis lucifugus, the little brown bat, across a large portion of northwestern USA, using a four-year detection history matrix obtained from a regional monitoring program. This widespread and abundant species has experienced precipitous local population declines in northeastern USA resulting from the novel disease white-nose syndrome, and is facing likely range-wide declines. Our models were temporally dynamic and accounted for imperfect detection. Drawing on species-energy theory, we included measures of net primary productivity (NPP) and forest cover in models, predicting that M. lucifugus occurrence probabilities would covary positively along those gradients. Despite its common status, M. lucifugus was only detected during -50% of the surveys in occupied sample units. The overall naive estimate for the proportion of the study region occupied by the species was 0.69, but after accounting for imperfect detection, this increased to -0.90. Our models provide evidence of an association between NPP and forest cover and M. lucifugus distribution, with implications for the projected effects of accelerated climate change in the region, which include net aridification as snowpack and stream flows decline. Annual turnover, the probability that an occupied sample unit was a newly occupied one, was estimated to be low (-0.04-0.14), resulting in flat trend estimated with relatively high precision (SD = 0.04). We mapped the variation in predicted occurrence probabilities and corresponding prediction uncertainty along the productivity gradient. Our results provide a much needed baseline against which future anticipated declines in M. lucifugus occurrence can be measured. The dynamic distribution modeling approach has broad applicability to regional bat monitoring efforts now underway in several countries and we suggest ways to improve and expand our grid-based monitoring program to gain robust insights into bat population status and trend across large portions of North America. 相似文献
193.
Busch J Dave R Hannah L Cameron A Rasolohery A Roehrdanz P Schatz G 《Conservation biology》2012,26(3):408-419
We examined the cost of conserving species as climate changes. We used a Maxent species distribution model to predict the ranges from 2000 to 2080 of 74 plant species endemic to the forests of Madagascar under 3 climate scenarios. We set a conservation target of achieving 10,000 ha of forest cover for each species and calculated the cost of achieving this target under each scenario. We interviewed managers of projects to restore native forests and conducted a literature review to obtain the net present cost per hectare of management actions to maintain or establish forest cover. For each species, we added hectares of land from lowest to highest cost per additional year of forest cover until the conservation target was achieved throughout the time period. Climate change was predicted to reduce the size of species' ranges, the overlap between species' ranges and existing or planned protected areas, and the overlap between species' ranges and existing forest. As a result, climate change increased the cost of achieving the conservation target by necessitating successively more costly management actions: additional management within existing protected areas (US$0-60/ha); avoidance of forest degradation (i.e., loss of biomass) in community-managed areas ($160-576/ha); avoidance of deforestation in unprotected areas ($252-1069/ha); and establishment of forest on nonforested land within protected areas ($802-2710/ha), in community-managed areas ($962-3226/ha), and in unprotected areas ($1054-3719/ha). Our results suggest that although forest restoration may be required for the conservation of some species as climate changes, it is more cost-effective to maintain existing forest wherever possible. 相似文献
194.
Lotfi Harrabi Patricia I Dolez Toan Vu-Khanh Jaime Lara 《International journal of occupational safety and ergonomics》2008,14(1):61-68
Two mechanical methods have been developed for the characterization of the flexibility of protective gloves, a key factor affecting their degree of usefulness for workers. The principle of the first method is similar to the ASTM D 4032 standard relative to fabric stiffness and simulates the deformations encountered by gloves that are not tight fitted to the hand. The second method characterizes the flexibility of gloves that are worn tight fitted. Its validity was theoretically verified for elastomer materials. Both methods should prove themselves as valuable tools for protective glove manufacturers, allowing for the characterization of their existing products in terms of flexibility and the development of new ones better fitting workers' needs. 相似文献
195.
Patricia B.C. Forbes Egmont R. Rohwer 《Environmental pollution (Barking, Essex : 1987)》2009,157(8-9):2529-2535
A novel analytical method for atmospheric polycyclic aromatic hydrocarbons (PAHs) was developed based on laser induced fluorescence (LIF) of samples on quartz multi-channel polydimethylsiloxane traps. A tunable dye laser with a frequency doubling crystal provided the excitation radiation, and a double monochromator with a photomultiplier tube detected emitted fluorescence. The method allowed for the rapid (<5 min), cost effective analysis of samples. Those yielding interesting results could be further analysed by direct thermal desorption-gas chromatography–mass spectrometry (TD–GC–MS, with limits of detection of ~0.3 ng m?3), as photodegradation was minimal (<10% over 5 min irradiation). Small amounts of naphthalene photodegradation products identified by TD–GC–MS after >15 min irradiation, included phenol, benzyl alcohol and phthalic anhydride. Without any signal optimization, a LIF detection limit of ~1 μg m?3 was established for naphthalene using a diffusion tube (diffusion rate of 2 ng s?1) and 292 nm excitation. 相似文献
196.
197.
Kent R Bass CR Woods W Sherwood C Madeley NJ Salzar R Kitagawa Y 《Traffic injury prevention》2003,4(4):297-314
Thoracic deformation under an applied load is an established indicator of injury risk, but the force required to achieve an injurious level of deformation currently is not understood adequately. This article evaluates how two potentially important factors, loading condition and muscle tensing, affect the structural response of the dynamically loaded thorax. Structural models of two human cadaver thoraxes and two porcine thoraxes were used to quantify the effects. The human cadavers, which represent anthropometric extremes, were subjected to anterior loading from (1) a 5.1-cm-wide belt oriented diagonally (i.e., seatbelt-like loading), (2) a 15.2-cm-diameter rigid hub, and (3) a 20.3-cm-wide belt oriented laterally (i.e., a distributed load). A structural model having the mathematical formulation of a quasilinear viscoelastic material model was used to model the elastic and viscous response, with ramp-hold tests used to determine the model coefficients. The effect of thoracic musculature was assessed using similar ramp-hold tests on the porcine subjects, each with and without forced muscle contraction. Even maximally contracted thoracic musculature is shown to have a minimal effect on the response, with similar elastic and viscous characteristics exhibited by each subject regardless of muscle tone. The elastic response is shown to be approximately a factor of three stiffer for diagonal belt loading and for this distributed loading condition than for the hub loading, indicating that the response is influenced most by the particular anatomical structures that are engaged and, secondarily, by the area of load application. Specifically, shoulder involvement is shown to have a strong influence. The force relaxation is found to be pronounced, but insensitive to the loading condition, with long-time force relaxation coefficients (G( infinity )) in the range of 0.1 to 0.3. The findings of this study provide restraint-specific guidelines for the force-deflection characteristics of both physical and computational thoracic models. 相似文献
198.
California and other regions in the United States are becoming more populated and ethnically diverse, and thus, ecological
impacts on the wildland–urban interface are a significant policy concern. In a socioeconomic assessment focused on the geographic
regions surrounding four national forests in southern California, population projections are being formulated to assist in
the update of forest plans. In southern California, the projected trend of explosive population growth combined with increased
ethnic and racial diversity indicates four challenges for environmental management. First, patterns of recreation use on wildlands
are likely to change, and management of these areas will have to address new needs. Second, as land-management agencies face
changing constituencies, new methods of soliciting public involvement from ethnic and racial groups will be necessary. Third,
growth in the region is likely to encroach upon wildland areas, affecting water, air, open space, and endangered species.
Fourth, in order to address all these concerns in a climate of declining budgets, resource management agencies need to strengthen
collaborative relationships with other agencies in the region. How environmental managers approach these changes has widespread
implications for the ecological sustainability of forests in southern California. 相似文献
199.
Patricia Bobrow Barbara Gaige Glenn Harris Joyce Kennedy Leslie King William Raymond Darrin Werbitsky 《Environmental management》1984,8(1):45-53
This study compares the effectiveness of two regional planning agencies in terms of public support for various planning activities. The Adirondack Park Agency and the Temporary State Commission on Tug Hill have fundamentally different approaches to planning. The Adirondack Park Agency has implemented a restrictive regulatory program with little citizen participation by Adirondack residents. The Tug Hill Commission has implemented an advisory and coordinating program with an emphasis on public input. Residents of two towns in each region were surveyed to determine environmental concern and support for regional planning activities. Respondents from both regions favored a planning agency that incorporates citizen input; controls air, water, and toxic waste pollution; and develops recreation areas. They strongly opposed an agency that regulates private land-use. Basic demographic characteristics and levels of environmental concern were similar in all four towns, but receptivity to various planning activities was consistently greater among residents of the Tug Hill Region. Paired comparisons of the four towns demonstrated no differences between towns of the same region and significant differences between towns of different regions. Public support for regional planning is greater in the Tug Hill Region than in the Adirondack Park. 相似文献
200.
Joshua S. Stoll Eliza J. Oldach Taylor Witkin Kathleen Reardon David C. Love Patricia Pinto da Silva 《Ambio》2022,51(4):926
Climate change, overfishing, and other anthropogenic drivers are forcing marine resource users and decision makers to adapt—often rapidly. In this article we introduce the concept of pathways to rapid adaptation to crisis events to bring attention to the double-edged role that institutions play in simultaneously enabling and constraining swift responses to emerging crises. To develop this concept, we draw on empirical evidence from a case study of the iconic Maine lobster (Homarus americanus) industry. In the Gulf of Maine, the availability of Atlantic herring (Clupea harengus) stock, a key source of bait in the Maine lobster industry, declined sharply. We investigate the patterns of bait use in the fishery over an 18-year period (2002–2019) and how the lobster industry was able to abruptly adapt to the decline of locally-sourced herring in 2019 that came to be called the bait crisis. We found that adaptation strategies to the crisis were diverse, largely uncoordinated, and imperfectly aligned, but ultimately led to a system-level shift towards a more diverse and globalized bait supply. This shift was enabled by existing institutions and hastened an evolution in the bait system that was already underway, as opposed to leading to system transformation. We suggest that further attention to raceways may be useful in understanding how and, in particular, why marine resource users and coastal communities adapt in particular ways in the face of shocks and crises.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01617-8. 相似文献