Finding and establishing new subpopulations

当一个动物亚种群灭绝时，剩余的个体就会分散寻找新的栖息地，以形成新的亚种群。我计划研究这个过程的三个步骤-搜索，发现栖息地补丁，并建立在这些栖息地补丁亚种群。 我建议找出哪些类型的运动模式是最成功的栖息地补丁，这种成功如何取决于栖息地补丁的分布，哪些运动模式的小型哺乳动物实际上使用时，在未知的栖息地旅行，以及如何使用的运动模式的类型取决于栖息地类型。我还将测量感知范围（从多远，他们可以检测到栖息地补丁）的变化与栖息地和距离家庭范围的小型哺乳动物在实验操作的栖息地。 将使用小型哺乳动物（田鼠和小鼠）进行实地实验。这些动物价格便宜，易于使用，使我们能够快速获得大样本量。这些动物将被跟踪使用无线电遥测和线程线轴相结合。将使用新开发的统计技术分析移动路径，区分随机移动和定向移动。 一旦动物找到一个新的栖息地，它们就需要建立一个新的亚种群。我的研究的第三部分将着眼于在可变环境中建立新的亚群。当亚群很小时，随机事件对成功的机会有很大的影响。 我还建议找出人口规模如何影响生存概率，以及条件的变化如何影响生存率。 这项工作将使用海狸进行。随机事件是冲垮水坝的风暴。当水坝很小时，它们很容易被暴风雨冲垮。我建议在一个大的区域调查水坝，然后比较水坝的成功从一个季节到下一个季节，作为水坝大小和风暴大小的函数。

When a subpopulation of animals goes extinct, then residual individuals disperse in search of new habitat patches to start new subpopulations. I plan to study three steps of this process - searching, discovering habitat patches, and establishing subpopulations in those habitat patches.     I propose to find out which types of movement patterns are most successful for finding habitat patches, how this success depends on the distribution of habitat patches, which movement patterns do small mammals actually use when travelling in unknown habitats, and how the type of movement pattern used depends on habitat type. I will also measure how perceptual range (from how far away they can detect the habitat patches) varies with habitat and distance from home range for small mammals in experimentally manipulated habitats.     The field experiments will be carried out using small mammals (voles and mice). These animals are cheap and easy to work with, allowing us to get large sample sizes quite quickly. The animals would be tracked using a combination of radio-telemetry and thread-spooling. Movement paths would be analysed using a newly-developed statistical technique that differentiates between random and directed movement.     Once animals find a new habitat patch, they need to establish a new subpopulation. The third part of my research will look at the establishment of new subpopulations in variable environments. When subpopulations are small, random events have a large impact on the chance of success.     I also propose to find out how population size affects survival probability, and how variability in conditions affects survival rate.     This work would be carried out using beavers. The random events are storms that wash out dams. When dams are small, they are easily washed out by storms. I propose to survey dams over a large area, and then compare the success of the dams from one season to the next, as a function of dam size and size of storms.