Sánchez-Hernández Javier, Gabler Heidi-Marie, Amundsen Per-Arne
Department of Arctic and Marine Biology Faculty of Biosciences Fisheries and Economics UiT The Arctic University of Norway Tromsø Norway; Department of Zoology, Genetics and Physical Anthropology Faculty of Biology University of Santiago de Compostela Santiago de Compostela Spain.
Department of Arctic and Marine Biology Faculty of Biosciences Fisheries and Economics UiT The Arctic University of Norway Tromsø Norway.
Ecol Evol. 2017 Feb 26;7(7):2058-2068. doi: 10.1002/ece3.2793. eCollection 2017 Apr.
Although food resource partitioning among sympatric species has often been explored in riverine systems, the potential influence of prey diversity on resource partitioning is little known. Using empirical data, we modeled food resource partitioning (assessed as dietary overlap) of coexisting juvenile Atlantic salmon () and alpine bullhead (). Explanatory variables incorporated into the model were fish abundance, benthic prey diversity and abundance, and several dietary metrics to give a total of seventeen potential explanatory variables. First, a forward stepwise procedure based on the Akaike information criterion was used to select explanatory variables with significant effects on food resource partitioning. Then, linear mixed-effect models were constructed using the selected explanatory variables and with sampling site as a random factor. Food resource partitioning between salmon and bullhead increased significantly with increasing prey diversity, and the variation in food resource partitioning was best described by the model that included prey diversity as the only explanatory variable. This study provides empirical support for the notion that prey diversity is a key driver of resource partitioning among competing species.
尽管在河流系统中，人们经常探讨同域物种之间的食物资源分配情况，但猎物多样性对资源分配的潜在影响却鲜为人知。利用实证数据，我们对共存的幼年大西洋鲑（）和高山杜父鱼（）的食物资源分配（以饮食重叠度衡量）进行了建模。纳入模型的解释变量包括鱼类丰度、底栖猎物多样性和丰度，以及几个饮食指标，总共17个潜在的解释变量。首先，使用基于赤池信息准则的向前逐步程序来选择对食物资源分配有显著影响的解释变量。然后，使用选定的解释变量并将采样地点作为随机因素构建线性混合效应模型。随着猎物多样性的增加，鲑鱼和杜父鱼之间的食物资源分配显著增加，并且食物资源分配的变化最好由仅将猎物多样性作为解释变量的模型来描述。本研究为猎物多样性是竞争物种间资源分配的关键驱动因素这一观点提供了实证支持。
