Mosquito Larval Collections from February 2020

Surveillance for mosquito larvae is a priority in the winter, as seasonal water sources have filled with rain water. A technician uses a dipper to take a sample of the water and visually inspects it for mosquito larvae. If larvae are present, the technician transports the sample to the laboratory for counts and identification. This February, 91 larval samples were submitted to the laboratory. The most frequently occurring species in larval samples was Culiseta incidens, the cool weather mosquito, present in 38 of the 91 samples. This mosquito is found year-round in a variety of sources, especially backyard fountains and fish ponds. It is not known to transmit diseases. Aedes washinoi, the fresh water mosquito, Culiseta inornata, the winter marsh mosquito, and Culiseta particeps, were also collected frequently this past month. Ae. washinoi is an aggressive mammal-biting mosquito that develops in fresh water marshes and ponds. The larvae of Cs. inornata breed in during the cooler months of the year, and can be found in both saline and fresh water sources. Cs. particeps breeds in natural fresh water sources and feeds on large mammals but does not vector disease.

Number and percentage of larval samples containing each mosquito species collected in larval samples in February 2020.