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  • What is the sound of fear? Behavioral responses of white-crowned sparrows Zonotrichia leucophrys to synthesized nonlinear acoustic phenomena

    Fear?and?anxiety?may?be?adaptive?responses?to?life-threatening?situations,?and?animals?may?communicate?fear?to?others?vocally.?A?fundamental?understanding?of?fear?inducing?sounds?is?important?for?both?wildlife?conservation?and?management?because?it?helps?us?understand?how?to?design?repellents?and?also?how?(and?why)?animals?may?be?negatively?impacted?by?anthropogenic?sounds.?Nonlinear?phenomena--sounds?produced?by?the?desynchronization?of?vibrations?in?a?sound?production?system-are?commonly?found?in?stress-induced?animal?vocalizations,?such?as?in?alarm?calls,?mobbing?calls,?and?fear?screams.?There?are?several?functional?hypotheses?for?these?nonlinear?phenomena.?One?specific?hypothesis?is?the?unpredictability?hypothesis,?which?suggests?that?because?nonlinear?phenomena?are?more?variable?and?somewhat?unpredictable,?animals?are?less?likely?to?habituate?to?them.?Animals?should,?therefore,?have?a?prolonged?response?to?sounds?with?nonlinear?phenomena?than?sounds?without?them.?Most?of?the?studies?involving?nonlinear?phenomena?have?used?mammalian?subjects?and?conspecific?stimuli.?Our?study?fo-?cused?on?white-crowned?sparrows?(Zonotrichia?leucophrys?ssp.?oriantha)?and?used?synthesized?acoustic?stimuli?to?investigate?behavioral?responses?to?stimuli?with?and?without?nonlinear?phenomena.?We?predicted?that?birds?would?be?less?relaxed?after?hearing?a?stimulus?with?a?nonlinear?component.?We?calculated?the?difference?from?baseline?of?proportion?of?time?spent?in?relaxed?behaviors?and?performed?pair-wise?comparisons?between?a?pure?tone?control?stimulus?and?each?of?three?experimental?stimuli,?including?a?frequency?jump?up,?a?frequency?jump?down,?and?white?noise.?These?comparisons?showed?that?in?the?30q50?s?after?the?playback?experiment,?birds?were?significantly?less?relaxed?after?hearing?noise?or?an?abrupt?frequency?jump?down?an?octave?but?not?an?abrupt?frequency?jump?up?an?octave?or?a?pure?tone.?Nonlinear?phenomena,?therefore,?may?be?generally?arousing?to?animals?and?may?explain?why?these?acoustic?properties?are?commonly?fou
    Ellen K. BLESDOE,Daniel T. BLUMSTEIN - 动物学报(英文版)
    文章来源: 万方数据
  • Foraging site recursion by forest elephants Elephas maximus borneensis

    Recursion?by?herbivores?is?the?repeated?use?of?the?same?site?or?plants.?Recursion?by?wild?animals?is?rarely?investigated?but?may?be?ubiquitous.?Optimal?foraging?theory?predicts?site?recursion?as?a?function?of?the?quality?of?the?site,?extent?of?its?last?use,?and?time?since?its?last?use?because?these?influence?site?resource?status?and?recovery.?We?used?GPS?collars,?behaviour?and?site?sampling?to?investigate?recursion?to?foraging?sites?for?two?elephant?Elephas?maximus?borneensis?herds?in?the?Lower?Kinabatangan?Wildlife?Sanctuary,?Borneo,?over?a?12?month?period.?Recursion?occurred?to?48?out?of?87?foraging?sites?and?was?most?common?within?48?hours?or?between?151-250?days,?indicating?two?different?types?ofrecursion.?Recursion?was?more?likely?to?occur?if?the?site?had?previously?been?occupied?for?longer.?Moreover,?the?time?spent?at?a?site?at?recursion?was?the?same?as?the?time?spent?at?the?site?on?the?first?occasion.?The?number?of?days?that?had?passed?between?the?first?visit?and?recursion?was?also?positively?correlated?with?how?much?time?was?spent?at?the?site?at?recursion.?Habitat?type?also?influenced?the?intensity?of?site-use,?with?more?time?spent?at?recursion?within?riverine/open?grass?areas?along?forest?margins?compared?to?other?habitat?types.?Recursion?is?a?common?behaviour?used?by?the?elephants?and?its?pattern?suggests?it?may?be?a?foraging?strategy?for?revisiting?areas?of?greater?value.?The?qualities?of?recursion?sites?might?usefully?be?incorporated?into?landscape?management?strategies?for?elephant?conservation?in?the?area?[Current?Zoology?60?(4):?551-559,?2014].
    Megan ENGLISH,Marc ANCRENAZ,Graeme GILLESPIE,Benoit GOOSSENS,Sen NATHAN,Wayne LINKLATER - 动物学报(英文版)
    文章来源: 万方数据
  • 斯巴鲁成功举办 2012年生态环保之旅 完成对江苏大丰麇鹿国家级自然保护区探访

    6月16日,斯巴鲁汽车(中国)有限公司与国家林业局下属中国野生动物保护协会联合举办的"2012年斯巴鲁生态环保之旅"圆满结束.在本次活动中,由斯巴鲁汽车(中国)有限公司工作人员、国家林业局野生动物保护协会工作人员、多家媒体人员以及斯巴鲁车主组成的考察团完成了对江苏大丰麋鹿国家级自然保护区的探访.
     - 汽车实用技术.自驾游
    文章来源: 万方数据
  • Human activity affects the perception of risk by mule deer

    Human activity has been shown to influence how animals assess the risk of predation, but we know little about the spatial scale of such impacts. We quantified how vigilance and flight behavior in mule deer Odocoileus hemionus varied with distance from an area of concentrated human activity--a subalpine field station. An observer walked trails at various distances away from the station looking for deer. Upon encounter, the observer walked toward the focal animal and noted the distance at which it alerted and directed its attention to the approaching human (Alert Distance; AD), and the distance at which it fled (Flight Initiation Distance;. FID). AD and FID both increased nonlinearly with distance from the center of the field station, reaching pla- teaus around 250 m and 750 m, respectively. Deer also tended to flee by stotting or running, rather than by walking, when far from the station but they walked away when near the station. These results indicate that deer perceive lower risk near a focused area of human activity, and that vigilance and flight behaviors respond on somewhat different spatial scales. The concept of a spatial "human footprint" on behavior may be useful for understanding how human activities affect wildlife
    Mary V. PRICE,Evelyn H. STROMBOM,Daniel T. BLUMSTEIN - 动物学报(英文版)
    文章来源: 万方数据
  • 雷殿生车行阿尔金

    阿尔金山国家级自然保护区是中国四大无人区之一,保留了最完整、原始的高原生态类型,有雪山沙漠的纯净美景和许多珍稀野生动物,具有很高的科学考察和探险旅游价值.今年"五一"期间,原本计划尝试徒步穿越这片无人区的"中国徒步第-人'雷殿生,却机缘巧合地成就了一段自驾之旅.
    路客,毛虫,刘旭 - 汽车实用技术.自驾游
    文章来源: 万方数据
  • 武陵春

    当野生的水芹、藜蒿疯长被风吹动的村庄里有着无边无际的繁荣苜蓿、青荇、马齿苋、胡葱与一岁一荣的时光并行而来那些纵横的阡陌,沉默的村落像一年年一茬茬一辈辈的初民生长、葳蕤、枯萎
    唐益红 - 诗刊
    文章来源: 万方数据
  • A survey for Batrachochytrium salamandrivorans in Chinese amphibians

    For the last decade, chytridiomycosis was considered to be caused by a single species of fungus, Batrachochytrium dendrobatidis (Bd), but a second chytrid species, Batrachochytrium salamandrivorans (Bs), was recently isolated from an in- fected Salamandra salamandra in the Netherlands. To date, Bs has only been found in the Netherlands. To assess whether Bs is present in China, we analyzed a total of 665 samples, including 425 wild samples, 41 preserved specimens, and 199 captive sam- pies, from 30 different species, including both urodeles and anurans. Our sample sites covered 15 provinces in China. All of the samples tested negative for Bs, resulting in a 95% confidence limit for a prevalence of 0.6%. The absence of Bs observed in this large-scale survey in China has significant implications for amphibian conservation and for border trade management strategies intended to control amphibian diseases. We strongly recommend the continued close monitoring of Bs to verify the status of this potentially devastating amphibian fungus in China .
    Wei ZHU,Feng XU,Changming BAI,Xuan LIU,Supen WANG,Xu GAO,Shaofei YAN,Xianping LI,Zetian LIU,Yiming LI - 动物学报(英文版)
    文章来源: 万方数据
  • 活动名称 蘑菇花

    注意:有些蘑菇是有毒的.在采摘野生蘑菇后,一定要彻底清洗双手.千万不要食用不认识的植物或菌类.实验中需要使用小刀,年龄较小的实验者需要有成年人在场指导协助实验.
     - 中国科技教育
    文章来源: 万方数据
  • 鱇浪白鱼野生与养殖群体遗传多样性的ISSR分析

    采用ISSR(inter-simple sequence repeat)标记对鱇浪白鱼野生与养殖群体的遗传多样性和遗传结构进行分析.从40条引物中筛选出了13条用于扩增,共检测到97个位点,其中多态性位点72个.鱇浪白鱼野生群体的遗传多样性(PPB=62.89%; H=0.2490;I=0.3636)高于养殖群体的遗传多样性(PPB=58.76%; H=0.2267; I=0.3314).结果表明,鱇浪白鱼总体遗传多样性水平较高.基于Nei's遗传多样性分析得出的野生与养殖群体间的遗传分化系数Gst=0.0826,分子变异分析(AMOVA)结果显示Fst=0.0796,2种方法揭示的鱇浪白鱼群体间的遗传分化的趋势基本一致,表明约8%遗传变异存在于群体间,遗传变异大多存在于群体内.UPMGA聚类树中,野生与养殖群体大多各自相聚,再相互混杂,群体间的基因流Nm(5.55)比较高,说明野生群体和养殖群体间有一定程度的遗传分化,但没有达到种群遗传分化的水平,在遗传上有一定的交流空间.
    刘红艳,熊飞,董元火,张繁荣,杨东,余来宁 - 华中师范大学学报(自然科学版)
    文章来源: 万方数据
  • Antipredator deception in terrestrial vertebrates

    Tim CARO - 动物学报(英文版)
    文章来源: 万方数据
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