Menezes Jorge F S, Kotler Burt P, Dixon Austin K
Marco and Louise Mitrani Department of Desert Ecology, SIDEER, BIDR, Ben-Gurion University of the Negev, Midreshet Ben-Gurion, 8499000, Israel.
Behav Processes. 2019 May;162:97-103. doi: 10.1016/j.beproc.2019.01.015. Epub 2019 Feb 1.
In this study, we addressed how frequently a non-traplining animal should visit food patches. More specifically, we investigate if non-traplining animals engage in a behavior called "defense by exploitation", which is characterized by an increase in visitation rates with increased intra-specific competition. We ran four tests with two gerbil species in the Negev Desert. Firstly, we measured patch use of Gerbillus pyramidum and Gerbillus andersoni allenbyi. We assumed that activity and competition would decrease through the night and that patch use would decrease with number of visits. Secondly, we measured how the number of visits to resource patches increased with the addition of individuals. Thirdly, we repeated this experiment, but instead removed individuals. Lastly, we conducted a simulation to compare these results against theoretical expectations. In the first test, we found support for defense by exploitation in G. pyramidum. The second and third test found no support. The fourth test found support for this increase visitation, but only if costs of locomotion are relatively small.
在本研究中，我们探讨了非陷阱觅食动物应多频繁地访问食物斑块。更具体地说，我们研究了非陷阱觅食动物是否会表现出一种被称为“通过利用进行防御”的行为，其特征是随着种内竞争加剧，访问率会增加。我们在内盖夫沙漠对两种沙鼠进行了四项测试。首先，我们测量了埃及沙鼠和罗氏沙鼠对斑块的利用情况。我们假设活动和竞争会在夜间减少，并且斑块利用会随着访问次数的增加而减少。其次，我们测量了随着个体数量的增加，对资源斑块的访问次数是如何增加的。第三，我们重复了这个实验，但改为移除个体。最后，我们进行了一次模拟，将这些结果与理论预期进行比较。在第一个测试中，我们发现埃及沙鼠存在通过利用进行防御的证据。第二个和第三个测试没有发现相关证据。第四个测试发现了支持访问增加的证据，但前提是移动成本相对较小。
