Feeding ecology of the orb-weaving spiderArgiope aurantia [Araneae: Araneidae] in a cotton agroecosystem

Twenty females of the orb-weaving spiderArgiope aurantia Lucas were introduced into a cotton field in east Texas in order to study the feeding ecology of this spider. In the 24 h after the release of these spiders in the cotton field, one had moved over a distance of 53 m. The released spiders spun webs with an average diameter of 33.5 cm with the hub an average of 39 cm above the ground. The diet ofA. aurantia was diverse which characterizes this species as a food generalist. Major food components were aphids (30%), Diptera (26.8%), grasshoppers (17.9%), and Hymenoptera (12.6%). The spiders' prey length ranged from 0.4 to 47 mm (mean =7.7±0.83 mm). Adult females ofA. aurantia have the potential to kill prey of up to ca. 200% of their own size. However, two-thirds of the prey items had a length of <3 mm, while only 25% of the prey items had a length of ≥20 mm.A. aurantia was found to be a predator of the cotton fleahopper (about 1% of the spiders' diet), which is a key pest of cotton.