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71.
Mice find endophyte‐infected seed of tall fescue unpalatable – implications for the aviation industry
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Bird strike is a significant problem for the aviation industry, caused in part by the attractiveness of the grass surrounding airports to birds. Endophyte‐infected grasses such as Avanex® have been shown to reduce bird populations at airports through the production of secondary metabolites. These metabolites are unpalatable to herbivorous, omnivorous and granivorous birds and are known to reduce insect densities, thereby making the sown areas less attractive to insectivorous birds. Raptors also provide a bird‐strike threat which could be reduced by controlling mouse populations around airports. In this study, the effect of endophyte‐infected seed on mouse feeding behaviour has been investigated. By performing a choice trial offering diets containing endophyte‐infected and endophyte‐free tall fescue seed, it was shown that endophyte‐infected seed was less palatable to mice (P < 0·001 in a 14‐d trial). Furthermore, when diet positions were reversed, mouse feeding behaviour was modified to again select endophyte‐free material (P < 0·001 over a further 14 d). This result shows that endophyte‐infected grasses could not only be used in the control of bird populations but they also have the potential to control mouse populations which in turn would decrease the number of raptors. This use of endophyte‐infected grasses in areas surrounding airport runways shows great promise for the aviation industry. 相似文献
72.
Amanda C J Vincent Yvonne J Sadovy de Mitcheson Sarah L Fowler Susan Lieberman 《Fish and Fisheries》2014,15(4):563-592
All possible tools need to be marshalled for marine fish conservation. Yet controversy has swirled around what role, if any, the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) should play for marine fishes. This paper analyses the relevance and applicability of CITES as a complementary tool for fisheries management. CITES currently regulates the international trade of very few marine fish species, by listing them in its Appendices. After the first meeting of the Parties (member countries) in 1976, no new marine fish taxa were added to the CITES Appendices until 2002, when Parties agreed to act to ensure sustainable and legal international trade in seahorses (Hippocampus spp.) and two species of sharks. Progress has continued haltingly, adding only one more shark, humphead wrasse (Cheilinus undulatus) and sawfishes by 2012. Parties voice concerns that may include inadequate data, applicability of CITES listing criteria, roles of national fisheries agencies, enforcement challenges, CITES' lack of experience with marine fishes, and/or identification and by‐catch problems. A common query is the relationship between CITES and other international agreements. Yet all these arguments can be countered, revealing CITES to be a relevant and appropriate instrument for promoting sound marine fisheries management. In reality, Parties that cannot implement CITES effectively for marine fishes will also need help to manage their fisheries sustainably. CITES action complements and supports other international fisheries management measures. As CITES engages with more marine fish listings, there will be greater scope to analyse its effectiveness in supporting different taxa in different contexts. 相似文献
73.
Leela Hazzah Monique Borgerhoff Mulder Laurence Frank 《Biological conservation》2009,142(11):2428-2437
African lion (Panthera leo) populations are in decline throughout most of Africa, but the problem is particularly acute in southern Kenya, where Maasai people are spearing and poisoning lions at a rate that will ensure near term local extinction. Lion killing is shaped by Maasai perception of livestock depredation, socio-economic factors, and the complex relationship between Maasai and conservation. These all affect tolerance for lions and consequently Maasai behavior towards conservation initiatives and carnivores in general. We used an in-depth quantitative questionnaire and participatory rural appraisals (PRAs) to identify the social and ecological predictors of lion killing and to investigate the effect of a compensation scheme on individual tolerance. Individuals who lose a greater proportion of their livestock to predators relative to their overall livestock loss, those affiliated with an evangelical church, and those who mainly sell rather than accumulate livestock all reported a higher propensity to kill carnivores. The future of carnivore conservation in this region depends on a better understanding of the nuances of human–carnivore conflict and a concerted effort to address appropriate cultural and community-level institutions, chiefly by providing economic benefits to local people who engage in positive conservation activities. 相似文献
74.
75.
Md. Ariful Islam Mst. Minara Khatun Byeong-Kirl Baek Sung-Il Lee 《Journal of veterinary science (Suw?n-si, Korea)》2009,10(3):211-218
Immunizing animals in the wild against Brucella (B.) abortus is essential to control bovine brucellosis because cattle can get the disease through close contact with infected wildlife. The aim of this experiment was to evaluate the effectiveness of the B. abortus strain RB51 vaccine in protecting infection as well as vertical transmission in Sprague-Dawley (SD) rats against B. abortus biotype 1. Virgin female SD rats (n = 48) two months of age were divided into two groups: one group (n = 24) received RB51 vaccine intraperitoneally with 3 × 1010 colony forming units (CFU) and the other group (n = 24) was used as non-vaccinated control. Non-vaccinated and RB51-vaccinated rats were challenged with 1.5 × 109 CFU of virulent B. abortus biotype 1 six weeks after vaccination. Three weeks after challenge, all rats were bred. Verification of RB51-vaccine induced protection in SD rats was determined by bacteriological, serological and molecular screening of maternal and fetal tissues at necropsy. The RB51 vaccine elicited 81.25% protection in SD rats against infection with B. abortus biotype 1. Offspring from rats vaccinated with RB51 had a decreased (p < 0.05) prevalence of vertical transmission of B. abortus biotype 1 compared to the offspring from non-vaccinated rats (20.23% and 87.50%, respectively). This is the first report of RB51 vaccination efficacy against the vertical transmission of B. abortus in the SD rat model. 相似文献
76.
Danilo Araujo Soares Pereira Marcelo Barbosa Henriques 《Aquaculture Economics & Management (Blackwell Science)》2013,17(4):428-448
AbstractThe L46 (Hypancistrus zebra) stands out as one of the most valuable Amazonian species in the international market for ornamental fish and faces a notable problem: the risk of extinction versus the demand for new specimens for aquariums. Considering that breeding in captivity can be a conservational tool for aquatic species and an alternative source for generating income, the objective of the present paper was to verify the economic feasibility of producing H. zebra in recirculation aquaculture systems (RAS), in different scenarios of rearing: residential breeding (S1), mid-size store production (S2) and large-scale production as a supplier (S3). The main profitability indicators used were: net present value (NPV), internal rate of return (IRR) and payback period (PP). The selling price per unit was fixed in US$260.15 (S1/S2) and US$156.09 (S3). The largest investments were made with the acquisition of broodstocks (S1/S2) and property (S3), while the highest costs were with labor (S2/S3) and taxes (S1). Only S1 demonstrated economic profitability (NPV 8.50%?=?US$28,187.85; IRR?=?74.71%; PP?=?1.80?years). Conclusion: the production in this study appeared to be profitable on smaller scales, however the profitability of large-scale production depends upon reducing expenses and increasing the selling price. 相似文献
77.
黑龙江凤凰山自然保护区野猪秋季生境选择 总被引:1,自引:1,他引:0
为掌握黑龙江省凤凰山国家级自然保护区内野猪种群的空间分布现状与迁移规律,于2009年秋、冬两季,应用样线调查法和样方调查法对野猪的生境选择情况进行调查,结合Vanderloeg和Scavia选择系数(W1)与选择指数(Ei)分析评估野猪对15个生境因子的偏爱程度,用秩和检验方法比较了野猪选择样方与非选择样方的差异.结果... 相似文献
78.
自然保护区野生动物保护成效评价研究综述 总被引:4,自引:0,他引:4
野生动物保护对于自然保护区尤其是野生动物类型的自然保护区来说是其保护工作的重要组成部分, 因此野生动物的保护成效是自然保护区保护功能和作用是否得到有效发挥的衡量标准之一。文中从野生动物的种类、种群数量、种群生存力、分布格局以及栖息地适宜性等方面总结了野生动物保护成效评价研究, 提出几种野生动物保护成效评价研究的可能途径和方法, 对野生动物保护成效评价研究进行了初步展望, 以期为今后野生动物保护成效研究提供理论和技术上的支持, 为自然保护区的建设和管理提供合理建议。 相似文献
79.
在回顾国内外野生动物价值评估方法的基础上, 初步界定了野生动物资源商业价值的概念以及构成分类, 通过对现有野生动物资源价值评估方法(市场价值法、成本法、意愿调查法、旅行费用法等)进行改进, 设计了野生动物资源商业价值的动态评估方法体系, 具体包括野生动物资源活体商业价值、野生动物产品商业价值、娱乐观光商业价值以及其他商业价值的动态评估方法; 最后选取亚洲象为案例进行了应用试算, 得出以2013年为基期其总体商业价值为354 734.665万元, 并给出了总体商业价值动态评估公式. 相似文献
80.
国内外野生动物肇事现状及其防控措施 总被引:1,自引:1,他引:0
人类活动范围的不断扩张导致野生动物栖息地随之缩小。野生动物肇事现象日趋严重, 造成的农作物损失和人员伤亡事件日益增多, 破坏庄稼、伤害家禽与家畜、伤人是野生动物主要的3种肇事类型。如何防控野生动物肇事以及怎样减少人兽冲突是野生动物肇事相关研究中的热点。文中概述了各肇事类型中典型性动物的肇事现状, 归纳了野生动物肇事的5类防控措施, 包括物理防控、化学防控、生物防控、基因防控以及通过管理手段进行的防控, 并提出了研究展望, 以期加深对人类与野生动物冲突的认识, 并为野生动物防控技术的研发提供参考。 相似文献