Departments > Coos Health & Wellness > Public Health > Environmental Health > Mosquito-Vector

Read the 2015 Year End Mosquito Report for Bandon Marsh

Read the VDCI 2015 Operations Report for their contract with Coos County 

Read the VDCI larvacide treatment reports from April 2015 to September 2015

This website shows Coos County's involvement in mosquito control work on the Bandon Marsh in 2014 and 2015.

Beyond the 2015 Year End report there is no plan to update this site.  


Standing water following a high tide that is not washed away by the next high tide provides potential habitat where the Aedes dorsalis could mature into an adult biting mosquito.  The restoration work creating the Ni’ les-tun unit of the marsh (up river of the US 101 bridge crossing the Coquille River) resulted in many acres of Aedes dorsalis habitat. 


Drainage channels have since been constructed to minimize the habitat.  The long-term, ideal includes, “No need to use federal, state or local tax dollars for mosquito control.”


Vector Disease Control International (VDCI) has contracted with Coos County to provide mosquito control on the Bandon Marsh while the drainage work has taken place.  VDCI has also provided some mosquito treatment away from the Bandon Marsh where habitat is conducive for Aedes dorsalis.  Most of the work done by VDCI is expected to be at the expense of the USFWS.  Funds for mosquito control work are not anticipated beyond 2015. 


Use of Bti insecticide for mosquito control is based on the on-going monitoring of larva during warm seasons.  For monitoring and treatment purposes a map of the marsh is divided into areas.  Use this link to view the current Larvacide Application Map

Periodically, traps are set overnight on or near the marsh to catch adult mosquitoes.  Trapped mosquitoes are identified by species and counted.  Use this link to see recent data for adult mosquito that have been trapped on or near the marsh.  Adult Trap Data

Limited arbovirus testing for mosquitos trapped between May 20th and June 26th showed no signs of West Nile Virus, Western Equine Encephalitis and St Louis Encephalitis. You can see the OSUVDL results by clicking this link:  OSUVDL Results

NOTE: These lab results also indicate some arbovirus testing for mosquitos trapped in the same time from around the old Kentuck Golf Course located at 94469 Golf Course Ln, North Bend.

Vector Assessment and Control progress in Bandon

During the warm months of 2013, the intensity of the biting salt water mosquito, Aedes dorsalis,in the vicinity of the USFWS Ni' les-tun unit of the Bandon Marsh caused an unmeasurable amount of suffering to people seeking outdoor activity in the area. This website is focused on the salt water mosquito, Aedes dorsalis, and the effectiveness of the work to control it.  For additional information on understanding the Aedes dorsalis, CLICK HERE.  


April 22-24, 2015      First Bti larvacide treatment for 2015              

March 2015:               Vector Disease control International (VDCI) is selected to contract with Coos County to provide mosquito control on the Ni-les tun unit of the USFWS Bandon Marsh.

Early Winter 2015:     USFWS issues a Special Use Permit to Coos County to provide mosquito control on the Bandon Marsh.

Information from 2014:

The USFWS maintains a related website at:

Oregon Department of Fish and Wildlife has completed some adult mosquito trapping in Coos County.  Use the links below to see the data available related to this work.

Some common terms of interest to search on the web might include:


    Aedes dorsalis


    Bacillus thuringiensis israelensis
    Mosquito Trapping


This website shows Coos County's involvement in mosquito control work on the Bandon Marsh in 2014 and 2015.
Beyond the 2015 Year End report there is no plan to update this site.  

Contact Us

Environmental Health

Program Manager:
Rick Hallmark, EHS, MPA

Phone: 541-266-6744

Office Hours
Monday - Friday
8 am  to 5 pm

Mosquito Survey

Mosquito Trapping Survey

Adult mosquito traps are periodically set in the vicinity of the Bandon Marsh to measure the presence of the salt water mosquito Aedes dorsalis.  
You can see results here (2015 Data)
  It may be difficult to compare the number of mosquitoes between trapping days as there are many variables
effecting results such as wind speed, precipitation, time of day for trapping and the effectiveness of pesticide use in the area.

2014 Mosquito Survey Data

Mosquito Adult Data Graph Provided by Bill Bridgeland, USFWS Wildlife Biologist
Adult Mosquito Data Link