title: Road facilitation of trematode infections in snails of northern Alaska.
abstract: Road disturbances can influence wildlife health by spreading disease agents and hosts or by generating environmental conditions that sustain these agent and host populations. I evaluated field patterns of trematode infections in snails inhabiting ponds at varying distances from the Dalton Highway, a wilderness road that intersects northern Alaska. I also assessed the relationships between trematode infections and snail densities and six environmental variables: calcium concentration, aquatic vegetative cover canopy cover temperature, pond size, and community structure. Presence of trematode infections and snail density were negatively correlated with distance from the highway. Of the pond characteristics measured, only calcium concentration and vegetation density declined with distance from road. However neither variable was positively associated with snail density or trematode presence. One potential explanation for observed patterns is that vehicles, road maintenance, or vertebrate vectors attracted to the highway facilitate colonization of snails or trematodes. Emerging disease threats to biological diversity in northern ecosystems highlight the importance of understanding how roads affect disease transmission.
authors.affiliation: Yale University, School of Forestry and Environmental Studies, Yale University, 370 Prospect Street, New Haven, CT 06511-2104, USA. mark.urban@yale.edu
authors.forename: Mark C
authors.initials: MC
authors.lastname: Urban
mesh_terms: D000413:Alaska; D000818:Animals; D004777:Environment; D005843:Geography; D012908:Snails / Q000469:parasitology*; D014200:Trematoda / Q000502:physiology*