Are invasive populations characterized by a broader diet than native populations?

PeerJ

article

Julien Courant¹  Solveig Vogt²  Raquel Marques⁴  John Measey³  Jean Secondi⁵  Rui Rebelo⁴  André De Villiers³  Flora Ihlow²  Charlotte De Busschere⁷  Thierry Backeljau⁷  Dennis Rödder²  Anthony Herrel¹ 

[1] UMR 7179, Département d’Ecologie et de Gestion de la Biodiversité, Centre National de la Recherche Scientifique;Herpetology Section;Centre for Invasion Biology, Stellenbosch University;Centre for Ecology, Evolution and Environmental Changes, Faculdade de Ciências da Universidade de Lisboa;UMR5023 Ecologie des Hydrosystèmes Naturels et Anthropisés, ENTPE, CNRS, Université de Lyon, Université Lyon 1;UMR 6554 LETG –LEESA, Université d’Angers;Royal Belgian Institute of Natural Sciences;Evolutionary Ecology Group, University of Antwerp;Evolutionary Morphology of Vertebrates, Ghent University

关键词: Diet breadth;    Trophic niche;    African clawed frog;    Invasive;    Electivity;    Native;   

DOI  :  10.7717/peerj.3250

学科分类：社会科学、人文和艺术（综合）

来源: Inra

【 摘 要 】

BackgroundInvasive species are among the most significant threats to biodiversity. The diet of invasive animal populations is a crucial factor that must be considered in the context of biological invasions. A broad dietary spectrum is a frequently cited characteristic of invasive species, allowing them to thrive in a wide range of environments. Therefore, empirical studies comparing diet in invasive and native populations are necessary to understand dietary requirements, dietary flexibility, and the associated impacts of invasive species.MethodsIn this study, we compared the diet of populations of the African clawed frog, Xenopus laevis in its native range, with several areas where it has become invasive. Each prey category detected in stomach contents was assigned to an ecological category, allowing a comparison of the diversity of ecological traits among the prey items in the diet of native and introduced populations. The comparison of diets was also performed using evenness as a niche breadth index on all sampled populations, and electivity as a prey selection index for three out of the six sampled populations.ResultsOur results showed that diet breadth could be either narrow or broad in invasive populations. According to diet and prey availability, zooplankton was strongly preferred in most cases. In lotic environments, zooplankton was replaced by benthic preys, such as ephemeropteran larvae.DiscussionThe relative proportions of prey with different ecological traits, and dietary variability within and between areas of occurrence, suggest that X. laevis is a generalist predator in both native and invasive populations. Shifts in the realized trophic niche are observed, and appear related to resource availability. Xenopus laevis may strongly impact aquatic ecosystems because of its near complete aquatic lifestyle and its significant consumption of key taxa for the trophic relationships in ponds.

【 授权许可】

CC BY