Pattern of seasonal variation in rates of predation between spider families is temporally stable in a food web with widespread intraguild predation

Intraguild predation (IGP) – predation between generalist predators (IGPredator and IGPrey) that potentially compete for a shared prey resource – is a common interaction module in terrestrial food webs. Understanding temporal variation in webs with widespread IGP is relevant to testing food web theory. We investigated temporal constancy in the structure of such a system: the spider-focused food web of the forest floor. Multiplex PCR was used to detect prey DNA in 3,300 adult spiders collected from the floor of a deciduous forest during spring, summer, and fall over four years. Because only spiders were defined as consumers, the web was tripartite, with 11 consumer nodes (spider families) and 22 resource nodes: 11 non-spider arthropod taxa (order- or family-level) and the 11 spider families. Most (99%) spider-spider predation was on spider IGPrey, and ~90% of these interactions were restricted to spider families within the same broadly defined foraging mode (cursorial or web-spinning spi..., Study system
We collected spiders and potential non-spider prey from the oak-dominated (Quercus alba and Q. rubra) Swallow Cliff Woods (41° 40.519’ N, 87° 51.437’ W) within the 320-ha Swallow Cliff nature preserve in Palos Township, Illinois (USA). The preserve, which is within the Chicago metropolitan region, is managed by the Cook County Forest Preserve District. Forests in this region are actively managed for several invasive plants (23), and the forest floor at Swallow Cliffs contains a thick leaf-litter layer with an abundant and diverse arthropod community. 
Collecting spiders and non-spider prey
Our goal was to search the ground layer and low understory as thoroughly as possible, so that we would collect enough spiders from less-abundant families to yield the same number of spiders per family analyzed for prey DNA. We did not estimate spider densities. All collections were made between 1000 and 1600 hours. We collected from a different location each day. The size of the area sear..., , # Pattern of seasonal variation in rates of predation between spider families is temporally stable in a food web with widespread intraguild predation

[https://doi.org/10.5061/dryad.dz08kps43](https://doi.org/10.5061/dryad.dz08kps43)

Metadata for manuscript entitled “Pattern of seasonal variation in rates of predation between spider families is temporally stable in a food web with widespread intraguild predation”.

Authors:
David H. Wise
Department of Biological Sciences, University of Illinois, Chicago, IL 60607, USA
[e-mail]

Robin M. Mores
2474 N. Lake Shore Drive, Apt. 4708, Chicago, IL 60611, USA
[e-mail]

Jennifer Pajada-De La O
Department of Mathematics, Statistics, and Computer Science, University of Illinois, Chicago, IL, 60607, USA
[e-mail]

Matthew A. McCary
Department of BioSciences, Rice University, Houston, TX 77005, USA
[e-mail]

File list (files can be found at https://github.com/mmccar26/spider-focused-food-web):
Contingency\...