Fleas exhibit a preference for warm and moist environments, and their peak activity occurs from July through October. Adult fleas reside on hosts, which can include various species such as cats, dogs, rats, and chickens, depending on the flea species.

Adult fleas sustain themselves by feeding on the blood of their host, and remarkably, they can survive for several months without a blood meal. Flea larvae primarily consume organic debris but also require blood, obtained from blood excrement left by adult fleas.

The flea life cycle progresses through the stages of egg, larva, pupa, and adult. Female fleas typically lay 4 to 8 eggs on the host after each blood meal, accumulating between 400 and 500 eggs in their lifetime. These eggs easily dislodge from the host's hair and land in areas frequented by the host. Hatching can occur within two days to two weeks, with the time taken to transition from egg to adulthood influenced by factors such as species, temperature, humidity, and food resources. Fleas may take anywhere from two weeks to eight months to reach adulthood. During winter, fleas often hibernate in their larval or pupal stages. In the pupal stage, fleas encase themselves in a silken cocoon, and adults emerge when they detect a nearby host through cues like body heat, noise, vibrations, and breathing. Fleas are most abundant during warm and humid winters and springs.