UC Santa Cruz
Avian Roosting Behavior and Vector-Host Contact Rates for West Nile Virus Hosts
- Author(s): Janousek, William M.
- Advisor(s): Kilpatrick, A. Marm
- et al.
Transmission of vector-borne disease is driven by contact rates between vectors and hosts. However, little is known about what drives fine-scale variation in mosquito host seeking behavior and the resulting consequences for contact patterns between mosquitoes and their hosts. We examined the roosting behavior of seven avian hosts of West Nile virus (WNV) and patterns of mosquito abundance among communal roost and non-communal roost sites and at different heights where birds roosted. We found some variation in roosting height among avian species coupled with increases in host-seeking mosquito densities higher in the canopy suggesting avian species experience differing vector contact rates influenced by their preferred roosting height. Prior research suggests host-seeking mosquito abundance increase with host group size, however in contrast to a priori predictions, we found significantly fewer host-seeking Culex mosquitoes at American robin communal roosts than non-communal roost sites, and far lower per capita biting mosquitoes and vector-host ratios at roost sites. Focusing specifically on American robins, the preferred host of Culex mosquitoes, our results suggest communal roosting behavior may reduce mosquito-biting rates on roosting individuals. Changes in American robin roosting behavior may partly explain previously observed seasonal changes in feeding patterns of Culex mosquitoes, which has direct implications for the transmission of WNV among birds and humans.