Abstract:
Intraspecific variation is an important form of biodiversity that can alter community and ecosystem properties. Recent work demonstrates the community effects of intraspecific variation in predators via altering prey communities and in foundation species via shaping habitat attributes. However, tests of the community effects of intraspecific trait variation in predators acting on foundation species are lacking despite the fact that consumption of foundation species can have strong community effects by shaping habitat structure. Here, we tested the hypothesis that intraspecific foraging differences among populations of mussel-drilling dogwhelk predators (Nucella) differentially alter intertidal communities through effects on foundational mussels. We conducted a 9-month field experiment where we exposed intertidal mussel bed communities to predation from three Nucella populations that exhibit differences in size-selectivity and consumption time for mussel prey. At the end of the experiment, we measured mussel bed structure, species diversity, and community composition. While exposure to Nucella originating from different populations did not significantly alter overall community diversity, we found that differences in Nucella mussel selectivity significantly altered foundational mussel bed structure, which in turn altered the biomass of shore crabs and periwinkle snails. Our study extends the emerging paradigm of the ecological importance of intraspecific variation to include the effects of intraspecific variation on predators of foundation species.
摘要:
种内变异是生物多样性的重要形式,可以改变群落和生态系统的特性。最近的工作证明了捕食者通过改变猎物群落和通过塑造栖息地属性在基础物种中种内变异的群落效应。然而,尽管基础物种的消费可以通过塑造栖息地结构而产生强大的群落效应,但仍缺乏对捕食者种内性状变异作用于基础物种的群落效应的测试。这里,我们检验了以下假设:贻贝钻探狗皮捕食者(Nucella)种群之间的种内觅食差异通过对基础贻贝的影响而不同地改变潮间带群落。我们进行了为期9个月的野外实验,在该实验中,我们将潮间带贻贝床群落暴露于三个Nucella种群的捕食中,这些种群在贻贝猎物的大小选择性和消耗时间上存在差异。实验结束时,我们测量了贻贝床结构,物种多样性,和社区组成。虽然暴露于来自不同种群的Nucella并没有显着改变整体群落多样性,我们发现Nucella贻贝选择性的差异显着改变了基本的贻贝床结构,这反过来改变了岸蟹和长春花蜗牛的生物量。我们的研究扩展了种内变异的生态学重要性的新兴范式,以包括种内变异对基础物种捕食者的影响。