Student paper on prey capture in Metellina mengei now out

by | Oct 30, 2020

An undergraduate project on edge effects in prey capture of Metellina mengei (family Tetragnathiae) in Wytham Woods near Oxford by Madeline Richards, has now been published in Animal Biology. The study builds on a previous study of web geometry, and finds that neither prey quantity (counted as prey caught in webs) nor prey length (most prey were small aphids in any case) differed between webs built at the forest edge and the forest interior strongly indicating that edge effects are negligible in this non-specialised orb spider. The only variable found to impact prey capture was inclination of the web, where interestingly mid inclination (slanted webs) had the highest success.

Richards, M. A. and Hesselberg, T. No edge effect on quantity of prey captured in the forest-dwelling tetragnathid orb spider Metellina mengei. Animal Biology. In Press. Early View: DOI 10.1163/15707563-bja10050.

Abstract
Among the most damaging anthropogenic effects for ecosystems is habitat fragmentation. One of its consequences is the creation of edges, which results in more exposed habitats that have different ecological and behavioural effects on the different species that live there. However, the nature and magnitude of these effects remain unknown for most of the animals and plants inhabiting these edge habitats. This study intends to determine if quantity of prey capture by a woodland population of the orb spider Metellina mengei is subjected to edge effects. By observing the prey capture of this species at edge and interior locations of a woodland, we found no significant effects of edge on the number of prey captured or the average prey length. Instead, we found that inclination of the web, but not web area or other measured web parameters, had a significant effect on prey capture. Therefore, this species of spider may be minimally affected by its location within the woodland and more affected by its surrounding microhabitat, which raises the possibility that non-specialised invertebrate predators could be less impacted by fragmentation than generally recognised.