Predation by wolf spiders (Lycosidae) on pest and non-pest insects found in blueberry fields in Washington County, Maine was investigated in the laboratory, greenhouse, and field. In laboratory experiments, four taxa of prey insects were evaluated as prey in no-choice arenas. Prey examined were blueberry spanworm Itame argillacearia (Packard) (Lepidoptera: Geometridae), blueberry flea beetle larvae, Altica sylvia Malloch (Coleoptera: Chrysomelidae), grasshopper (Acrididae) adults and nymphs, and field cricket (Gryllus pennsylvanicus Burmeister) (Orthoptera: Gryllidae) adults and nymphs. Lycosids consumed blueberry flea beetles, grasshopper nymphs, and field cricket nymphs but not blueberry spanworm, grasshopper adults, or field cricket adults. In greenhouse mesocosms, both grasshopper and house cricket (Acheta domestica Linnaeus) densities were lower in no-choice cages containing a single lycosid compared to control cages with no spiders; blueberry spanworm larvae densities were not significantly different between control and treated cages.
Two field experiments were conducted in which cages received equal quantities of several prey species and either zero (control), four, or eight lycosids. Significant differences in numbers of grasshoppers or house crickets recovered were not detected among treatments. There were significant differences in field crickets recovered. Fewer field crickets remained in cages containing more predators (spiders, carabid beetles, and ants). Although lycosids consumed some blueberry pest species, pest populations were not significantly lower in field cages containing lycosids.
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