Fleas are one of the smallest insects, but they can be the biggest pest problem anyone encounters. Difficult to get rid of, expensive and labor intensive, flea control can be the most time-consuming pest extermination project you could be swamped with. Not only are fleas difficult to kill with pest control treatments, but they can also withstand great pressure when being squeezed. Females are quite prolific and the pupal stage may lie in wait for up to a year for the right conditions and trigger its emergence. These two factors alone present a major challenge in flea eradication.
It is estimated that a flea population is around 50 percent eggs, 45 percent larvae and only 5 percent adults. Fleas can live and thrive in any area where a host can go, including but not limited to: Nests in trees, attics, lawns, homes, cars, RV’s, high-rise dwellings, boats, crawl spaces, caves, hotels, wall voids, etc. As you might imagine, a thorough understanding of the flea habits and lifecycle will be crucial to aid you in success.
Throughout history, fleas have developed a fearsome reputation. It is worth noting fleas contributed to the spread of the Black Plague, which is a disease that almost killed off the entire European continent. People often think rats were directly responsible for spreading the disease to humans, but it was actually the fleas that fed off the plague-carrying rats. These Fleas would then bite people and spread the pathogen to them. There are over 2,400 different kinds of fleas worldwide! The most common fleas a homeowner has to deal with are the Cat, Dog, Sticktight, and Northern Rat flea. Fleas have a complete life cycle meaning they go from egg to larva to pupa, and then adult. Each stage of flea has different preferences or tendencies for location, and far too often this is where treatment efforts are stifled.
Egg
The number of eggs laid depends on species, with batch sizes ranging from two to several dozen and lifetime numbers ranging from around one hundred to several thousand. Considering the relatively short lifespan of the adult, this is quite a number. In some species, the flea lives almost exclusively in the nest or burrow and the eggs are deposited there, but in others, the eggs are laid on the host itself but easily fall off onto the ground. Because of this, areas where the host rests and sleeps is an area to always check for the presence of flea eggs and larva. A single adult can lay between 40 and 50 in a single day and the eggs can hatch anywhere from two days to two weeks.
Larva
Flea larvae develop through three stages of varying duration, where they take the form of first, second, and third instars. At each respective stage, the larvae are referred to as first, second, or third instars. To clarify, the stages are called stages, and the physical larval forms are called instars. Flea larvae have chewing mouthparts and feed on any available organic material such as dead insects, adult flea feces, non viable flea eggs, and vegetable matter. It was long thought that the blood in the adult feces or at the base of fallen host hairs were the main ingredient in larva development but studies show that blood-only diets allow only 12% of larvae to mature, whereas a varied diet allowed almost all to develop. Consumption of non viable flea eggs took that number to 90%. They are blind and avoid sunlight, keeping to dark, humid places such as sand or soil, cracks and crevices, under carpets and in bedding. They will move to these areas in a home by wriggling towards the darkened area and a technician would be wise to lift rugs, move furnishings and have a bright flashlight in order to provide the most complete inspection and treatment.
Pupa
When the larva is ready it weaves a silken cocoon to pupate. Once inside the cocoon, the larva molts for a final time and undergoes metamorphosis into the adult form. This can be completed in as little as a week or take many months if conditions are not favorable. The pre emergent adult will wait inside until conditions are right and or certain “triggers” will cause it to emerge. These triggers include, vibrations, heat or increased carbon dioxide, all indicating a suitable host is present. With these factors in mind it’s easy to see why people returning from vacations or vacant homes that suddenly have activity can have a mass emergence and cause such a dramatic, seemingly out of nowhere infestation.
Adult
As mentioned above the adults you see feel and itch from represent a much smaller number of the fleas you actually are dealing with. It is strongly advised that you take steps and use products such as Igr’s to take on the entire population. The adult flea lives only a few short months (longer under ideal conditions) but without a host may die within days. Optimum temperatures for the flea’s life cycle are 70 °F to 85 °F and optimum humidity is 70%. Newly emerged fleas are quite aggressive and homeowners and pets can feel besieged by the sudden attack.