Impact of invasive honeysuckle and native trees on ecology of native and invasive mosquitoes

Despite the overlapping distribution of alien invasive plants and many native and alien invasive mosquito species, our understanding of potential implications of these plants for mosquito ecology and the risk of exposure to mosquito-borne diseases is limited. We examined how interaction of alien invasive honeysuckle (Lonicera maackii) with two native tree species, sugar maple (Acer saccharum) and northern red oak (Quercus rubra) influences oviposition site selection by Culex restuans, the vector of West Nile Virus, and pupal production and adult body size of Ochlerotatus triseriatus, the native vector of La Crosse virus, and Oc. japonicus, an alien invasive mosquito species. To accomplish this, single and mixed-species mesocosms (honeysuckle and individual tree species’ litter) were established at two field sites in Urbana Illinois. South Farm study site yielded significantly more Cx. restuans egg rafts and more and larger Ochlerotatus adults compared to Trelease Woods. Significantly more Cx. restuans egg rafts were deposited in honeysuckle infusions than in native tree species’ infusions. Mixing honeysuckle litter with native tree species’ litter had additive effects on Cx. restuans oviposition preference. There were no significant differences in Ochlerotatus pupal production among individual leaf species. However, mixing honeysuckle with native tree species resulted in additive effects on Ochlerotatus pupal production. Honeysuckle litter resulted in significantly larger adult females of Oc. triseriatus (at both sites) and Oc. japonicus (at South Farm) relative to native tree species’ litter. Mixing honeysuckle with native tree species resulted in additive effects on body size of Oc. triseriatus and Oc. japonicus females with exception of honeysuckle and northern red oak litter mixture which had antagonistic effects on female body size of Oc. triseriatus. These findings suggest the potential for honeysuckle invasions to enhance production of native and exotic mosquito species and possibly the risk of arbovirus transmission.