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Responses of two ecologically similar bear species (American black bear and Asiatic black bear) to human-dominated landscapes and consumptive use.

机译：两种生态上相似的熊物种（美洲黑熊和亚洲黑熊）对人类主导的景观和消费用途的反应。

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摘要

In addition to being closely related evolutionarily, the American black bear (Ursus americanus) and Asiatic black bear ( Ursus thibetanus) share strikingly similar ecologies. Both are opportunistic generalists that rely on diverse diets and occur across vast geographic ranges. Forest fragmentation, agricultural development, and other landscape-level changes arising from increasing human density have dramatically altered the continents inhabited by these species resulting in range contractions and population declines for both. In recent decades American black bears have rebounded throughout much of the Upper Midwestern United States in response to a cessation of unsustainable hunting. In contrast, declines of Asiatic black bears continue, driven at least in part by persistent, illegal killing. In this dissertation I present data from a study of movement, habitat use, and activity of subadult American black bears that occupied a region of west-central Wisconsin where forests were heavily fragmented, human activity was high yet bears were thriving. Movement, activity, habitat use, and proximity to roads and waterways were influenced by dispersal status and all bears capitalized on small forest patches when navigating the fragmented landscape. Direction of dispersal was not random, possibly influenced by varying densities of bears from north to south. I also present data from studies of free-ranging and captive Asiatic black bears in central China. The study of free-ranging bears was based on comparing concentrations of glucocorticoid metabolites in feces of Asiatic black bears collected in and around 8 nature reserves in central China. Natural food abundance and location of samples with respect to the boundaries of nature reserves were important factors in my analysis, underscoring the value of nature reserves in conserving superior habitats. My study of captive bears focused on documenting endocrinological differences between bears farmed for bile and those at a rehabilitation center, and tracking changes in endocrine parameters (hair and fecal glucocorticoids) that occurred in bears after removal from bile farms. Circulating levels of glucocorticoids declined markedly in Asiatic black bears removed from bile farms while responsiveness to various stimuli indicated resilience of the hypothalamic-pituitary-adrenal axis in this species.
机译：除了在进化上密切相关外，美洲黑熊（Ursus americanus）和亚洲黑熊（Ursus thibetanus）也有着极为相似的生态。两者都是机会主义的通才，他们依赖多种饮食，并且分布在广阔的地理范围内。由于人类密度的增加，森林破碎化，农业发展以及其他景观水平的变化极大地改变了这些物种所居住的大陆，导致这两种物种的范围缩小和人口减少。近几十年来，由于停止不可持续的狩猎，美国黑熊在美国中西部大部分地区反弹。相反，亚洲黑熊的数量继续下降，至少部分原因是持续的非法杀戮。在这篇论文中，我提供了来自美国黑熊的运动，栖息地利用和活动的数据，该黑熊占据了威斯康星州中西部的一片森林，该地区森林零散，人类活动活跃，但熊熊却蓬勃发展。运动，活动，栖息地的使用以及与道路和水路的接近都受到分散状态的影响，所有熊在漫游零散的景观时都利用小片森林作为资本。散布的方向不是随机的，可能受熊的密度从北到南的影响。我还介绍了来自中国中部自由放养和圈养的亚洲黑熊的研究数据。自由放养的熊的研究是基于比较在中国中部8个自然保护区及其附近收集的亚洲黑熊的粪便中糖皮质激素代谢物的浓度。在我的分析中，天然食物的丰富度和样品相对于自然保护区边界的位置是我分析的重要因素，强调了自然保护区在保护优越栖息地方面的价值。我对圈养熊的研究集中在记录为胆汁饲养的熊和在康复中心的熊之间的内分泌学差异，并跟踪从胆汁场移出后熊体内发生的内分泌参数（头发和粪便中的糖皮质激素）的变化。在从胆汁养殖场移出的亚洲黑熊中，糖皮质激素的循环水平显着下降，而对各种刺激的反应表明该物种的下丘脑-垂体-肾上腺轴具有弹性。

著录项

  • 作者

    Malcolm, Karl Day.;

  • 作者单位

    The University of Wisconsin - Madison.;

  • 授予单位 The University of Wisconsin - Madison.;
  • 学科 Agriculture Wildlife Management.;Biology Zoology.;Biology Ecology.
  • 学位 Ph.D.
  • 年度 2011
  • 页码 180 p.
  • 总页数 180
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类
  • 关键词

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