Flea Cycle Circus

If the Flea Circus has set up tents in your yard or on your pet this summer, you may feel like you're going in circles! There's a good reason for that - the life cycle of the flea and its resiliency. As shown in the illustration above (click to enlarge), fleas go through five main stages in their development from egg to adult. The female adult flea (#1) can lay ten to forty eggs per day, after a blood meal. That spins out to hundreds of flea eggs over a few month's time. Adult fleas are tiny - 1/8 of an inch long - so imagine how small their eggs are. So small, in fact, that you will have to imagine them, because you won't see these smooth, oval, white eggs roll right off  your pet and onto pet beds, favorite sofas, or carpet areas. Flea eggs hatch in two to ten days, into the larval stage (#3). The larvae like to stay in warm, protected environments. Depending on the temperature, they can feed on adult flea feces, which contain bits of dried blood, and crawl around for five to fifteen days before building their tiny cocoons (#4). Within these cocoons, larvae pupate into a stage also known as "pre-emergent adult" (#5). Fleas can stay in this pupal stage for months, waiting until their environment is right before hatching into adult fleas. Warm temperatures, humidity, vibrations, and carbon dioxide in the air trigger the pupae to emerge as fleas, ready to feed. Since the life cycle is extremely variable, lasting from two weeks to two years, flea control can be difficult. The best way to stop the cycle is to use a spray labeled for use against adult fleas that has a good residual, combined with an Insect Growth Regulator (IGR), which keeps eggs from hatching. 

To sum up our integrated pest management tips on flea control, pet owners should seek advice from veterinarians regarding topical applications of flea control. Vacuuming thoroughly and regularly helps by removing dead fleas and flea feces, which are a source of nourishment for larval and pupal fleas. Clearing the yard of harborage for urban wildlife that may carry fleas into your yard is also part of the process. If these methods do not control your flea problem, call in a pest professional who can apply a spray that will kill adult fleas and prevent flea eggs from hatching. Even after a professional application, it may take three weeks before the circus closes down and the fleas are evicted from your house.