Experimental manipulation of population density in a wild bird alters social structure but not patch discovery rate
Experimental manipulation of population density in a wild bird alters social structure but not patch discovery rate
复制标题
DOI：
10.1016/j.anbehav.2023.12.010
复制
发表时间：
2024-01-20
期刊：
影响因子：
2.5
通讯作者：
Sheldon，Ben C.
中科院分区：
文献类型：
--
作者：
Beck，Kristina B.;Regan，Charlotte E.;Sheldon，Ben C.
人口密度是影响个体之间社会交往机会的一个基本生态特征。因此，密度可以影响各种人口过程，例如社会传播。虽然疾病传播的密度依赖性已被广泛研究，但我们对密度变化如何影响信息传播知之甚少。如果高密度导致更多的社会联系，信息可能会传播得更快。在这里，我们实验性地操纵当地人口密度在大山雀，山雀，并调查个人的信息获取新的食物补丁的影响。我们通过在野外使用自动喂鸟器将个体分配到高密度或低密度处理来操纵密度。我们首先展示了我们的方法如何成功地导致当地人口密度的变化。接下来，我们研究操纵如何改变当地和个人的社会环境。在地方一级，与低密度地区相比，高密度地区的社交网络平均更为密集和密集。在个体水平上，分配到高密度处理的鸟类平均比低密度处理的鸟类有更多的社会联系和更多的中心网络位置。然而，尽管对网络结构的影响，我们没有发现任何证据表明，密度操纵影响个人的可能性，或速度，定位新的食物补丁。低密度处理的鸟类仍然花了很大一部分时间在高密度位置觅食。因此，该操作并未导致不同处理的禽类之间的严格隔离，这可能是对斑块发现无影响的一种解释。
Population density is a fundamental ecological feature influencing the opportunity for social encounters between individuals. Hence, density can impact various population processes such as social transmission. While the density dependence of disease spread has been studied extensively, we know little about how variation in density influences information transmission. If high densities lead to more social connections, information may spread more rapidly. Here, we experimentally manipulated local population density in great tits,Parus major, and investigated the effects on individuals' acquisition of information on novel food patches. We manipulated density by assigning individuals to either a high- or low-density treatment using automated bird feeders in the wild. We first show how our approach successfully led to changes in local population density. Next, we examine how the manipulation changed the local and individual social environment. At the local level, high-density locations resulted on average in denser and more clustered social networks compared to low-density locations. At the individual level, birds assigned to the high-density treatment had on average more social connections and more central network positions than birds in the low-density treatment. However, despite the effect on network structure, we found no evidence that the density manipulation influenced an individuals' likelihood, or speed, of locating novel food patches. Birds in the low-density treatment still spent a large proportion of time foraging at the high-density location. Thus, the manipulation did not lead to a strict segregation between birds of the different treatments, which may be one explanation for the absence of an effect on patch discovery.