Fleas prefer to live in humid, shady areas, although they can thrive in a variety of climates. In the wild they will typically live in debris piles, shrubs, tall grass, weeds, and wood piles. Around the outside of homes and businesses, they may live in places like dog houses, sheds, garages, and outdoor furniture. On dogs or cats, they tend to keep to the back, belly, and neck areas. Flea eggs do not stick to the host, and can therefore easily fall off and land anywhere. Once those eggs hatch, the fleas will infest anywhere in homes and businesses that regularly have human or pet activity.