Mosquito Control Program



Mosquito Control commences each spring in the Town of Salem. Crews begin checking vernal pools, swamps, catch basins, ditches, depressions, and other areas of shallow, stagnant water for mosquito larvae and pupae.

When mosquitoes are found, the following insecticides may be used:

  • VectoBac Bti (Bacillus thuringiensis israelensis)
  • Altosid (Methoprene)
  • Agnique MMF (poly-isooctadecyl-hydroxyl)

This type of treatment is called larviciding and it is a safe and effective method to prevent immature mosquitoes from developing into flying, biting adults. In some locations, predators feed on mosquito larvae which eliminates the need for spraying.

The spray schedule is based on mosquito surveillance data and weather conditions. Residents who do not want their property treated must contact Dragon Mosquito Control in writing at:
P.O. Box 46
Stratham, NH 03885

Otherwise, mosquitoes may be sprayed on your property, if necessary.


Another component of the Mosquito Control Program includes the trapping of adult mosquitoes. Typically, two to four traps are located within the town to collect adult mosquitoes in order to determine the extent of mosquito activity and the types of mosquitoes present. Over 20 species of mosquitoes have been identified in Salem and this information is important to conclude if we have the species that typically carry West Nile Virus or Eastern Equine Encephalitis. After identification, the mosquitoes are sent to the New Hampshire State Laboratory to determine if they are carrying either one of these viruses.

4th of July

In preparation for the 4th of July Celebration, control of adult mosquitoes will be done using permethrin and sumithrin. Areas to be sprayed are the High School and Junior High School fields and the "Field of Dreams". Residents may call Dragon Mosquito Control at 603-734-4144 or the Salem Health Department at 603-890-2050 for more information on spray dates, location, materials used, precautions, or other concerns including Eastern Equine Encephalitis and West Nile Virus.

Public Health Threats

If West Nile Virus or Eastern Equine Encephalitis becomes a public health threat in Salem, adulticiding (adult spraying) may be considered. Areas to be sprayed with permethrin and sumithrin will be determined based on locations of birds and mosquitoes found positive with one of these viruses. In addition, adulticiding may be recommended for athletic fields and school playgrounds. Public notice of this spraying will be disseminated to the residents including information on how to limit your exposure to these insecticides.

Important Note

The State Lab is no longer accepting dead birds from Salem for West Nile Virus or EEE testing. Positive birds have been identified throughout the state and it is unnecessary to continue this type of testing. Testing of mosquitoes is more accurate and important in determining if the virus is present in our town. If you find a dead bird, it can be discarded in the trash or by burial. Always use caution when handling any dead animal. Do not handle the bird with bare hands and use gloves or a shovel.