Seasonal Changes in Habitat Preference by Coleomegilla maculata: Implications for Colorado Potato Beetle Management in Potato

p r h i p b R ( 1 g W z i H c c Seasonal abundance, dispersal, and overwintering f the 12-spotted ladybird beetle, Coleomegilla macuata (DeGeer), in the mid-Atlantic states were investiated to assess the potential to manipulate the habitat f this predator to increase its impact on Colorado otato beetle, Leptinotarsa decemlineata (Say), mangement in commercial potato plantings. C. maculata opulations were highest in corn fields through Auust, and overwintering aggregations were found most ommonly in habitats adjacent to these fields. Alhough adult and larval populations of C. maculata ere synchronized with first-generation potato beetle ggs and small larvae, they were concentrated in heat rather than potato fields because most of the otato plants had not yet emerged when C. maculata dults dispersed from their overwintering sites. The ubsequent generation of C. maculata tended to aggreate in corn rather than potato in late May and early une. Therefore, given the current mixture of crops as ell as climatic and marketing limitations on planting ate for potatoes, the potential for habitat manipulaion to increase the impact of C. maculata on Colorado otato beetle management in potato in the midtlantic states appears to be limited. r 2000 Academic Press