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Mosquito

The Sheridan County Weed and Pest District (SCWPD) manages a mosquito vector control program throughout the unincorporated areas of Sheridan County. SCWPD staff monitor mosquito larva populations and initiate aerial larvicide applications along all major waterways in the County (see map). Typically, these larvicide applications will occur once in the months of June, July, and August depending on populations.

The product being used is Vectobac 12 AS. It is a naturally occurring material (biocontrol) which only affects mosquito, black fly, and fungus gnat larvae. The product is a bacteria 
which contains spores that produce deadly toxins stunting the growth or killing only the larvae mentioned before. This product will NOT affect, nor is harmful in any way to humans, honey bees, livestock, wildlife, fish or aquatic life.

SCWPD maintains a list of properties that prefer not to be part of this program. Property owners that wish to opt out of this program, or be notified when spraying operations are scheduled, are encouraged to call SCWPD at (307) 672-3740.

Track West Nile Virus in Wyoming

The above map shows in blue the major drainages of Sheridan County that get treated with Vectobac

For general mosquito control we cost-share two kinds of biological larvicide, sheets of BTI Briquets, and 40lb bags of granular Aquabac. These larvicides are used in water habitats where the mosquito larva can be effectively controlled.

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The above image shows a mosquito larva which is a little smaller than a grain of rice (1-6mm in length).

The above video shows how mosquito larvae swim around and use their siphon tubes to breath off the surface of the water.

What are we doing about West Nile Virus?

​A primary objective of the SCWPD mosquito vector control program is to determine if there is a presence of West Nile virus (WNV) in Sheridan County. SCWPD staff and community cooperators trap adult mosquitoes throughout the summer. Mosquitoes are sorted by species, and female Culex spp. are processed and subjected to testing for WNV using the RAMP®  system. Any mosquitoes that test positive are reported to the Wyoming Department of Health. SCWPD will also notify the Sheridan community of any presence of WNV through media releases and public information campaigns, urging the public to take additional precautions against mosquito bites.

Our adult mosquito traps are not for public use. Please do not disturb these traps if you happen to encounter them. Shown below is a picture of one.

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The above picture is a female Culex tarsalis mosquito. Some identifying features are its round abdomen tip, the white band on its proboscis (long nose), and the white bands on its legs. 

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The above picture is one of our adult mosquito traps ready to catch vector mosquitos.

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