 The total number of eggs produced in a female's lifetime (fecundity) varies from around one hundred to several thousand.In some species, the flea lives in the host's nest or burrow and the eggs are deposited on the substrate, but in others, the eggs are laid on the host itself and can easily fall off onto the ground.Because of this, areas where the host rests and sleeps become one of the primary habitats of eggs and developing larvae.