Fleas in the yard might come from neighborhood pets, strays or even wildlife and easily infest a home via the coming and going of domestic pets. Fleas thrive in warm, humid habitats.
There are 2500 species of flea worldwide, with over 300 of those occurring in the United States. The cat flea is the most common species and, contrary to its name, also infests dogs and wild animals like coyotes and opossums. The majority of fleas in the United States infest primarily mammalian hosts, with only 6 percent infesting birds. Because of the wide range of potential hosts, fleas, especially the cat flea, easily survive in residential lawns. Pets that come and go from homes to lawns then transport fleas from outdoors into the home. Adult female fleas lay 50 eggs per day. The eggs are not sticky and quickly fall from the host animal. If the animal is indoors the eggs fall to carpet and rugs to incubate. Flea larvae survive on the waste of adult fleas before forming a pupa. Adult fleas can emerge from pupae in as little as three days but may also remain dormant for over a year. Warm temperatures, vibrations and carbon monoxide trigger adult emergence. This means that treating the affected pet itself does not solve a flea infestation as new adults can simply emerge from pupae at a later time to start the cycle again.