title: Factors affecting immatures of Ochlerotatus taeniorhynchus (Diptera: Culicidae) in San Diego County, California.
abstract: The effects of tide, temperature, rainfall, and salinity on the occurrence and abundance of immatures (instars and pupae) of the black salt marsh mosquito, Ochlerotatus taeniorhynchus (Wiedemann), were examined at a tidal pond in the Tijuana Estuary during 1996-1998. Immatures were found between May and early September. Tide had the greatest influence on immatures of this mosquito. Eggs eclosed when tides averaged 1.96 +/- 0.10 (SD) m (1.83-2.19) 1-3 d before a flood tide. Eclosion averaged once every 14.4 d during 1996 (nine broods) and 1997 (eight broods) and once every 20.2 d during 1998 (six broods). Immatures were most abundant during late May-early August when tides were usually > or = 2.0 m, and mean (+/-SD) pond temperature was 27.6 +/- 2.6 degrees C (23.8-33.9) and salinity was 44.6 +/- 13.9 g/kg (33-95). Temperature primarily influenced egg diapause and influenced rate of development of immatures. Increased amounts of seasonal rainfall during 1997-1998 (42.9 cm: caused by El Niño), compared with 1995-1996 (11.4 cm) and 1996-1997 (17.3 cm), may have increased the mortality of overwintering eggs and/or diluted salinity of the substrate making it less conducive for oviposition.
authors.affiliation: Community Health Division, Department of Environmental Health, County of San Diego, 9325 Hazard Way, San Diego, CA 92123, USA.
authors.forename: James D
authors.initials: JD
authors.lastname: Lang
mesh_terms: D000818:Animals; D002140:California; D002980:Climate; D004777:Environment; D005260:Female; D005843:Geography; D018978:Molting; D044969:Ochlerotatus / Q000254:growth & development / Q000502:physiology; D010058:Oviposition / Q000502:physiology; D011156:Population Density; D012098:Reproduction / Q000502:physiology; D012621:Seasons