Do beetles eat spiders?
Insect and spider predators found in arable crops are known to consume crop pests, but also other invertebrates, known as alternative prey. These generalist natural enemies can attain high densities by feeding on alternative prey during the early growing season, before any pest outbreak occurs. This could be useful for pest control before specialist natural enemies, like parasitic wasps, appear. However, the alternative prey on which the generalist natural enemies feed also includes some species that are also pest natural enemies. This preliminary work looks at predation on money spiders (Linyphiidae), known to be effective aphid predators, by a ground beetle, Pterostichus melanarius, which consumes both slugs and aphids. We wanted to establish whether these beetles consumed any of these spiders and, if so, whether they show a preference for those species who also occur in the same places as the beetles.
