Consumption of black cutworms, Agrotis ipsilon (Lepidoptera: Noctuidae), and alternative prey by common golf course predators

Abstract

Turfgrass ecosystems contain a variety of generalist predators that may contribute to the regulation of pest insect populations. The black cutworm, Agrotis ipsilon (Hufnagel) (Lepidoptera: Noctuidae), is frequently a pest of short-mown golf course greens and fairways and may be a candidate for management by conservation biological control tactics. However, little is known about the susceptibility of different instar A. ipsilon to the many species of carabids, staphylinids, and spiders that inhabit greens, fairways, and roughs. These ecosystems also contain nonpest arthropods that could serve as alternative prey for generalist predators and help bolster their populations. In these laboratory experiments, 12 species of predators, commonly found on golf courses, were evaluated for their ability to consume five different instars of A. ipsilon and for their feeding voracity. The palatability of five potential alternative prey items, to a subset of predators, was also tested. All predator species tested were able to consume at least one instar of A. ipsilon. Two of the most common predators found on golf courses, Amara impuncticollis (Say) (Coleoptera: Carabidae) and Philonthus sp. (Coleoptera: Staphylinidae), could consume all A. ipsilon instars and were also among the most voracious predators tested. In addition, all five alternative prey items were readily eaten by the predator species that were tested. These results suggest that these generalist predators play a role in the regulation of A. ipsilon larval populations on golf courses and that several nonpest arthropod taxa could contribute to attracting and maintaining predator populations.