Amphibian population dynamics in disturbed landscapes

世界范围内的两栖动物种群正面临着人口下降和灭绝，比鸟类或哺乳动物更严重。由于其复杂的生命周期（水生和陆生生命阶段），池塘繁殖的两栖动物构成了一个有趣的挑战。池塘繁殖的两栖动物在不同的生命阶段和一年中的不同时间使用不同的栖息地类型。在给定的景观中，栖息地类型之间的移动相对于其他脊椎动物（< 1公里）是有限的，这使得两栖动物成为研究栖息地干扰对移动和人口参数影响的理想候选动物。然而，几个参数（例如，生存，招聘）量化人口动态与人类干扰所必需的仍然有待估计。在北方地区尤其如此，那里是许多物种的北方活动范围的极限，伐木活动向北移动，正在修建道路以进入采矿或森林资源。目前的建议侧重于模拟两栖动物种群动态在人为干扰的景观，并结合基础和应用组件。在这项研究计划中，我将量化道路和森林的做法对几个池塘繁殖两栖动物物种的人口参数的影响，通过复制和操纵现场实验和捕获标记重捕研究。在未来五年，我的研究目标包括：1）量化道路和汽车交通对两栖动物池塘殖民的影响; 2）量化道路对个体繁殖概率、生存和适应度的影响，以及它们对种群持续性的影响; 3）量化生境复杂性的影响（粗木质残体和树冠开度）对两栖动物在人工池塘定居的影响;以及4）估计在生命早期阶段经历的环境条件对生命后期阶段的存活的遗留效应。除了生活史策略和结转效应，我的工作的新颖和重要的方面包括道路和木本残体对两栖动物种群过程中的作用在北方地区。

Amphibian populations worldwide are facing population declines and extinctions, more so than either birds or mammals. With their complex life cycles (aquatic and terrestrial life stages), pond-breeding amphibians pose an interesting challenge. Pond-breeding amphibians use different habitat types during different life stages and at different times of the year. Movements between habitat types in a given landscape are limited relative to other vertebrates (< 1 km), which makes amphibians ideal candidates to investigate the effects of habitat disturbances on movements and demographic parameters. Yet, several parameters (e.g., survival, recruitment) necessary to quantify population dynamics in relation to human disturbances remain to be estimated. This is especially true in boreal regions, at the northern range limit of many species, with logging activities moving North and roads being built to access mining or forest resources. The current proposal focuses on modeling Amphibian Population Dynamics in Human-disturbed Landscapes, and combines fundamental and applied components. In this research program, I will quantify the effects of roads and forest practices on the demographic parameters of several pond-breeding amphibian species, through replicated and manipulative field experiments and capture-mark recapture studies. Over the next five years, my research objectives will consist in: 1) quantifying the effect of roads and car traffic on amphibian pond colonization; 2) quantifying the effect of roads on breeding probability, survival, and fitness of individuals, and their repercussions on population persistence; 3) quantifying the effect of habitat complexity (coarse woody debris and canopy openness) on the colonization of artificial ponds by amphibians; and 4) estimating carry-over effects of environmental conditions experienced during early life stages on the survival at later life stages. Beyond life history strategies and carry-over effects, the novel and significant aspects of my work include the role of roads and woody debris on amphibian population processes in boreal regions.