Mosquitoes are insects that spend most of their development in the water. Only adult mosquitoes spend time outside of water and can live anywhere from a week to a month. Due to early life stages needing water to develop, mosquitoes will find any available sources of standing water like ponds, streams, marshes, etc. However, they also will find areas of standing water in residential areas like bird baths, gutters, overturned garbage lids, etc.
Adult mosquitoes feed on nectar and plant juices. Most female mosquitoes require a blood meal to lay eggs. Male mosquitoes never bite.
Females typically feed at dawn and dusk and use a number of sensory receptors to find prey based on carbon dioxide, heat, perspiration, and other chemicals. While mosquitoes suck blood they also transfer their saliva. Sometimes that saliva contains a pathogen that can cause disease. In Ohio, Culex mosquitoes transmit West Nile virus to humans and horses, making them a serious threat to public health.
Mosquito life cycle. Males and females mate. Females will lay eggs in or near water so that the aquatic larvae can grow. They go through multiple molting phases before pupating and emerging as adults. (Picture link).
Image of adult male mosquito (left) and female mosquito (right). Palps are sensory organs that help mosquitoes detect chemicals. (Picture link).