Does prey characteristics influence web-building plasticity of the ecologically dominant orb-web weaving spider, Neoscona theisi (Walckenaer 1841)?

Abstract

Spiders are the pre-eminent silk producers and many species construct orb webs to capture the insect prey. The present study was focused on the design and the orientation patterns of Neoscona theisi orb webs, during the crop growing seasons of rice and wheat. Architectural design of webs constructed by the orb web spider was examined in the crop fields by walking through the fields to locate the spider webs. Results revealed that web height and diameter increased along with increase in the diversity and availability of insect pests of rice. The proportion of vertically oriented webs of N. theisi increased progressively with increase in the availability of highly active and large-sized, prey in the paddy fields. In the wheat agroecosystem, the proportion of spiders without webs increased in response to the availability of the most abundant, small sized (with very low mobility) aphid prey, Sitobion avenae. It is likely that the adaptive plasticity in web size and orientation patterns exhibited by N. theisi not only helps it to maximize its prey capture efficiency but also plays an important role in contributing towards its dominance among the orb web-making species. © 2022, African Association of Insect Scientists.