Baltimore Ecosystem Study Institute of Ecosystem Studies

2011 BES Annual Meeting Presentation and Poster Abstracts

Ecological complexity and disease vectors: Phenology and composition of urban mosquito communities in Baltimore
LaDeau, Shannon

Abstract: In the past decade, West Nile virus has had a persistent and dramatic impact on many North American bird species and has resulted in over 1000 human fatalities. The local intensity of avian and human incidence has been positively associated with human-dominated landscapes. The potential effects of landscape modification and interactions with changing climate are complex and likely to alter the ecological processes that define spatio-temporal patterns in composition and abundance of mosquito (vector) species and disease risk. We collected data in Baltimore, MD to test the hypothesis that urban breeding habitats support fewer mosquito species but greater abundances of WNV vector species. In 2010 and 2011 ovitraps were set out to collect weekly samples from egg-laying mosquitoes along the urban gradient from Baltimore City to a rural, reference watershed in the County. Over twelve species of mosquitoes were found, with distinct spatial and temporal patterns evident. While species richness supports an intermediate disturbance hypothesis, diversity indices (i.e., Shannon-Weiner) do decline at sites with higher impervious surface cover. Traps in the most urban settings (i.e., Watershed 263) supported a predominant invasive species community of mosquitoes, while the composition from the rural reference sites included both these same invasives and native (often non-human biting) species.