Adulticide

The adult stage the portion of the life cycle most people associate with mosquitoes.  The adult stage is the only stage in their life cycle in which they are not fully aquatic, and the only stage in which they take a blood meal.  After emerging from the pupal casing, the newly hatched adult will rest on top of the water to dry its wings and body.  Once dried, the mosquito is capable of flight

While it varies based on temperature and mosquito species, it can take only seven to ten days for a mosquito to go from egg to adult. 

With the basic biology of mosquitoes addressed, we can get into the details of how the District program works. 

Here at GCMCD No. 2, the vast majority of our applications target mosquito larvae.  The products used to kill mosquito larvae are extremely low in toxicity and do not affect other aquatic organisms.   

While this part of Grant County is a desert, there is an abundance of mosquito habitat.  This is due to the formation of Banks Lake in the Grand Coulee along with natural ponds notably above the Coulee throughout the district.

To determine if an area is breeding mosquitoes field technicians sample the habitat using a dipper.  A dipper is a small white cup attached to a long wooden handle.  The dipper is used to skim the water surface and the technician analyzes the sample taken for the presence of mosquito larvae and/or pupae.

The District also has an adult mosquito surveillance program consisting of trapping mosquitoes and identifying them to help in the formulation of effective control measures.  To capture mosquitoes, we use traps baited with carbon dioxide.  These traps consist of a carbon dioxide cylinder, battery operated fan and light, and an internal catch net. The carbon dioxide released from the cylinder will attract the mosquitoes.  From there they see the light above the fan and fly toward it.  As the mosquitoes reach the light, the fan will pull them down into the catch net where they cannot escape.  Upon collection, the catch net is separated from the fan, closed, and placed into a container with wet paper towels.  These paper towels allow the mosquitoes to drink water and regain moisture which is essential to keeping them alive.

Once the mosquitoes are transported back to the lab, the catch nets containing the mosquitoes are set into a freezer just before beginning the identification procedure.  The cold will put the mosquitoes to sleep so that they are easily identifiable.  The mosquitoes are then sorted into piles by genus and species.  

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