Mosquitoes are flying, biting insects that develop in water during their immature stages. Some of the many species found in New York are considered pests and can transmit diseases to humans and some animals. Mosquitoes are small flying insects that feed on human and animal blood or plant juices. Three are the most common species of mosquitoes in New York State. Only female mosquitoes bite to get a blood meal for their growing eggs. Mosquitoes usually become infected from feeding on infected birds. Mosquitoes lay their eggs in moist areas, such as standing water. The eggs become larvae that remain in the water until they mature into adults and fly off. Weeds, tall grass and shrubbery provide an outdoor home for adult mosquitoes. They also can enter houses, apartments and buildings through unscreened windows and doors. Many mosquitoes will breed in any container that holds water, such as flowerpots, wading pools or discarded tires. Some mosquitoes are active between dusk and dawn, when the air is calm. However, others will feed at any time of day. Mosquitoes prefer a warm, moist environment. They are active from early summer until late fall in New York State.