Their life cycle depends on the species. The eggs, larvae and pupae are aquatic among all mosquitoes, while the adults are aerial.
Mating takes place in flight or on plants. The fertilized female then sets off in search of a blood meal, as the protein is necessary for egg formation. A few days later, she lays 50 to 300 eggs, depending on the species, in different aquatic environments or on moist ground.
Once it hatches, the microscopic larva passes through four larval stages. When it has finished growing, it turns into a comma-shaped pupa, much stockier than the larva. The pupa does not feed, but it is active and may remain motionless just below the surface of the water. If disturbed, it dives to escape predators.
Adults emerge on the water surface. They stay there until their wings and bodies have dried. Males gather in swarms, and females come to join them.
For most of the mosquitoes in Quebec, eggs are laid in the summer and overwinter under the snow. They hatch early in the spring, and the larvae develop in the cold water of ponds formed by melting snow.