Brandon Buzz


The rainy days continue to flood the fields and various flood prone areas.  The region has been experiencing colder than usual temperatures, which may be impacting the emergence of adult mosquitoes.  The BLSG has been busy surveying the flood plains and wetlands to quantify the larvae counts and document the findings.

Surveying is a task performed by a field technician. The District has over 60 sites that are regularly surveyed for mosquito larva. These sites are reached by foot or in a small boat or the amphibious all-terrain vehicle, known as the ARGO.  Surveying a site includes using a dipper to sample water to determine what species are prevalent in the water. The District is looking for mosquito larva, but they are also looking for dragon fly larvae and other natural predators of mosquito larvae. The contents of the cup provide the technician with a window into the health and vitality of the area surveyed.

The technician keeps records of the temperature of the water and general observations made in the field. The water samples are first viewed on the spot for a preliminary estimate of the number of larvae present and, based on their size, their larval stage. This forms a preliminary opinion of the severity and timing of a future hatch.

The samples are returned to the BLSG lab where the larvae can be recounted and identified by species.  It is then entered into a database for analysis. This analysis is used as part of the District’s Integrated Pest Management Program. Sometimes the District rears the larvae in their lab to have pristine adult mosquito samples for future adult mosquito identification. Samples exceeding 10 larvae per dip are generally a cause for larvicide treatment.

In the past two weeks the technicians have sampled 79 sites. The typical larvae-per-cup was 20 to 50.  The highest count was 500/dip located in Pittsford. If these areas are small and accessible they are treated with larvicide by hand (or boat or ARGO) where possible and/or reported to the state for aerial treatment consideration. Currently, limited funds make an aerial treatment unlikely before July, however the District will continue to treat hotspots by hand and with the Argo. 

Given the generally high larvae counts, the public is urged to help by reducing or eliminating any standing water on your property. Every little bit helps reduce the future adult mosquito population.  Please visit the District website for more information at

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