TY - JOUR
T1 - Effects of warm winter temperature on the abundance and gonotrophic activity of culex (Diptera
T2 - Culicidae) in California
AU - Reisen, William
AU - Thiemann, Tara
AU - Barker, Chris
AU - Lu, Helen
AU - Carroll, Brian
AU - Fang, Ying
AU - Lothrop, Hugh D.
PY - 2010/2/1
Y1 - 2010/2/1
N2 - Culex tarsalis Coquillett, Cx. quinquefasciatus Say, and Cx. pipiens L. were collected during the warm winter of 2009 using dry ice-baited and gravid traps and walk-in red boxes positioned in desert, urban, and agricultural habitats in Riverside, Los Angeles, Kern, and Yolo Counties. Temperatures exceeded the preceding 50 yr averages in all locations for most of January, whereas rainfall was absent or below average. Abundance of Culex species in traps during January ranged from 83 to 671% of the prior 5 yr average in all locations. Few females collected resting were in diapause during January based on follicular measurements. Evidence for early season gonotrophic activity included the detection of freshly bloodied, gravid, and parous females in resting collections, gravid oviposition site-seeking females in gravid female traps, and nulliparous and parous host-seeking females at dry ice-baited traps. Female Culex seemed to employ multiple overwintering strategies in California, including larval and adult quiescence, adult female diapause, and an intermediate situation with adult females collected with enlarged follicles, but without evident vitellogenesis. West Nile, St. Louis, or western equine encephalitis viruses were not detected in 198 pools of adults or 56 pools of adults reared from field-collected immatures collected during January and February 2009. Our preliminary data may provide insight into how climate change may extend the mosquito season in California.
AB - Culex tarsalis Coquillett, Cx. quinquefasciatus Say, and Cx. pipiens L. were collected during the warm winter of 2009 using dry ice-baited and gravid traps and walk-in red boxes positioned in desert, urban, and agricultural habitats in Riverside, Los Angeles, Kern, and Yolo Counties. Temperatures exceeded the preceding 50 yr averages in all locations for most of January, whereas rainfall was absent or below average. Abundance of Culex species in traps during January ranged from 83 to 671% of the prior 5 yr average in all locations. Few females collected resting were in diapause during January based on follicular measurements. Evidence for early season gonotrophic activity included the detection of freshly bloodied, gravid, and parous females in resting collections, gravid oviposition site-seeking females in gravid female traps, and nulliparous and parous host-seeking females at dry ice-baited traps. Female Culex seemed to employ multiple overwintering strategies in California, including larval and adult quiescence, adult female diapause, and an intermediate situation with adult females collected with enlarged follicles, but without evident vitellogenesis. West Nile, St. Louis, or western equine encephalitis viruses were not detected in 198 pools of adults or 56 pools of adults reared from field-collected immatures collected during January and February 2009. Our preliminary data may provide insight into how climate change may extend the mosquito season in California.
KW - California
KW - Culex
KW - Diapause
KW - Overwintering
UR - http://www.scopus.com/inward/record.url?scp=77949300282&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=77949300282&partnerID=8YFLogxK
U2 - 10.1603/ME09207
DO - 10.1603/ME09207
M3 - Article
C2 - 20380305
AN - SCOPUS:77949300282
VL - 47
SP - 230
EP - 237
JO - Journal of Medical Entomology
JF - Journal of Medical Entomology
SN - 0022-2585
IS - 2
ER -