Mosquito Biology

Mosquitoes complete a full metamorphosis: egg, larva, pupa, and adult. Critical to the mosquito’s life cycle is water.  Egg rafts are laid on still or standing water. Each raft contains 100 - 300 eggs.  The eggs hatch to larvae.  The larvae grow through 4 instars, shedding their outer skin as they grow to the next stage. Once the larvae reach the 4th stage (or instar), they then transform to pupae. The pupal stage is the equivalent of the cocoon, where the adult insect body develops. Once development is complete, the pupae hatch off the water as adult mosquitoes.  The adult female then needs to take a “blood meal” to provide necessary nutrients to her eggs. In warmer weather, mosquitoes complete a full metamorphosis, on average, in seven to ten days.

San Joaquin County has seventeen types of common mosquitoes: Types of Mosquitoes

Mosquito Life Cycle


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