The Culex mosquito lays eggs one at a time on the surface of stagnant or fresh water, and then sticks 100 to 300 eggs together to form a "raft." Culex mosquito eggs typically hatch within two days.
Culex mosquito larvae live in the water but must surface periodically to breathe oxygen. The larval phase lasts from one to two weeks depending on the temperature of the water.
A Culex pupa floats on top of the water for one to four days while it transforms into an adult mosquito. The pupal phase is a non-feeding, resting stage.
A newly emerged, adult Culex mosquito rests on top of the water until its body is dry and hardened. Female Culex mosquitoes that emerge late in the summer hibernate in a sheltered area until spring.
All types of mosquitoes must have water to complete their life cycles. Culex mosquitoes prefer small bodies of still water full of organic matter, such as tin cans, bird baths or rain barrels.