Intraguild predation is increased in areas of low prey diversity in a generalist predator community

Authors

Stella F. Uiterwaal, University of Nebraska-LincolnFollow
Amber J. Squires, University of Nebraska-Lincoln
Bennett A. Grappone, University of Nebraska-Lincoln
Brian Dillard, Cornell University
Ariadne Castaneda, University of California
Sora L. Kim, University of California
John P. DeLong, Eagle Environmental, Inc.Follow

Date of this Version

2-2-2023

Citation

J Anim Ecol. 2023;00:1–12. DOI: 10.1111/1365-2656.13901

Comments

Open access.

Abstract

1. Niche differentiation and intraguild predation (IGP) can allow ecologically similar species to coexist, although it is unclear which coexistence mechanism predominates in consumer communities. Until now, a limited ability to quantify diets from metabarcoding data has precluded the use of sequencing data to determine the relative importance of these mechanisms.

2. Here, we pair a recent metabarcoding quantification approach with stable isotope analysis to examine diet composition in a wolf spider community.

3. We compare the prevalence of resource partitioning and IGP in these spiders and test whether factors that influence foraging performance, including individual identity, morphology, prey community and environmental conditions, can explain variation in diet composition and IGP.

4. Extensive IGP is likely the primary coexistence mechanism in this community, and other factors to which foraging variation is often attributed do not explain diet composition and IGP here. Rather, IGP increases as prey diversity decreases.

5. Foragers are driven to IGP where resource niches are limited. We highlight the need to examine how drivers of predator–prey interaction strengths translate into foraging in natural systems.