- Adult mosquitoes are small, fragile insects with slender bodies; one pair of narrow; and three pairs of long, slender legs.
- They have an elongate “beak” or piercing proboscis.
- The mosquito goes through four separate and distinct stages of its life cycle: Egg, Larva, pupa, and adult.
- Larviciding typically involves applying pesticides containing methoprene or Bacillus thuringiensis israelensis or B. sphaericus bacteria, to water where mosquito larvae develop.
- As mosquito larvae feed, the Bacillus are ingested. Once ingested, a bacterial toxin perforates the mosquito’s gut, killing it.
- Larvicides containing the insect growth regulator, methoprene, work by disrupting the larva’s metamorphosis, preventing it from developing into an adult.
- The toxicity of both types of larvicide is quite low, and both are considered safe to use in waters containing fish.
- Adulticiding is the process of applying a fog or mist of insecticide to reduce the number of adult mosquitoes.
- Mosquito adulticiding is conducted in the late afternoon hours, as this is the time of high mosquito activity.
- This type of treatment is only effective if there are adult mosquitoes flying at the time of fogging and if weather conditions are favourable for keeping the fog close to the ground.
- It does not provide residual protection against future mosquitoes.
- For this reason, adulticiding is done in conjunction with larviciding as treatment processes for mosquito control.