The Life Cycle of Fleas

There are four stages in the life cycle of a flea including egg, larvae, pupae and adult. Optimal conditions allow females to lay up to 2,000 eggs in her life span and expand the population quickly. It is best to use a monthly flea preventive to keep your pet and home flea-free.

The female flea lays eggs after she has a blood meal from a host -- your pet. She lays the eggs in your pet's fur in batches of around 20. Eggs are white and smaller than a grain of sand. Females can lay two batches, or about 40 eggs daily.

Eggs fall from your pet as he moves around, making up about 50 percent of the fleas in your home. Eggs take from two days to two weeks to hatch. Cold and dry temperatures delay the hatching, while warm humid environments expedite the hatching.

During the larvae stage eggs hatch a blind worm, which is 1/4-inch long and white. Larvae feed on flea dirt for several weeks to ingest predigested blood and other organic matter in the environment.

Larvae compose about 35 percent of the flea population in a home. Within 5 to 20 days, larvae spin a cocoon to enter the pupae stage.

The flea life cycle pupae stage is about 10 percent of the population in a house. The cocoon protects the pupae for several days to several weeks when the adult flea emerges. The cocoon can stay in place for months or years until the environmental conditions are acceptable.

Cocoons are sticky on the outside to make removal by vacuuming or sweeping more difficult. It protects the occupants from chemicals that kill them. When the pupae feels vibrations, body heat and sense a rise in carbon dioxide levels, it hatches sensing a host is nearby.

The adult flea emerges from the cocoon and needs to have a blood meal from a host within a few hours to survive. It breeds and lays eggs within a few days, starting a new life cycle.

Adult fleas are about 5 percent of the flea population in an environment. Most of an adult fleas life is spent on a host where they feed, breed and lay eggs.

The life span of a flea in the best conditions can last for two or three years.

Tapeworms attach themselves to a pet's inner intestine walls to feed. When worms mature, segments detach and exit the animal's body through feces. The small segments are white and look much like a grain of rice. They may appear around a host's anus and stick in his fur.

Once expelled, the tapeworm sections release eggs that flea larvae eat. When pets lick or chew to relieve themselves from flea bites, they can consume flea larvae containing tapeworm eggs. The eggs enter the digestive tract, hatch and attach to the inner intestines to restart the life cycle of tapeworms.