Attraction of Culex pipiens to House Sparrows Is Influenced by Host Age but Not Uropygial Gland Secretions
Department of Biology, Oberlin College, Oberlin, OH 44074, USA
Department of Chemistry and Biochemistry, Oberlin College, Oberlin OH 44074, USA
Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA
Author to whom correspondence should be addressed.
Insects 2018, 9(4), 127; https://doi.org/10.3390/insects9040127
Received: 27 August 2018 / Revised: 21 September 2018 / Accepted: 22 September 2018 / Published: 25 September 2018
(This article belongs to the Special Issue Integrative Mosquito Biology: From Molecules to Ecosystems)
Culex pipiens serves as the endemic vector of West Nile virus (WNV) in eastern North America, where house sparrows (HOSP, Passer domesticus) serve as a reservoir host. We tested the hypotheses that: (1) Attraction of Cx. pipiens to HOSP is influenced by bird age and (2) that age-specific variation in chemical profiles of bird uropygial gland secretions informs this choice. We conducted mosquito choice trials in an olfactometer and found that Cx. pipiens were more often attracted to adult sparrows over nestlings, however, they demonstrated no preference for adults over fledglings. Using gas chromatography-mass spectrometry we observed age-specific differences in the semi-volatile chemical profiles of house sparrow uropygial gland secretions. Contrary to our hypothesis, we found no significant difference in mosquito feeding preference between the secretions of adults and those of either nestlings or fledglings. We suggest that other chemical cues influence the feeding preference of Cx. pipiens, either independently of uropygial gland secretions, or synergistically with them.