There are more than 2,000 species of fleas worldwide. Knowing which flea species you are dealing with is necessary to develop an effective control strategy.
- Fleas undergo complete metamorphosis from smooth, white, oval, eggs about 0.5 mm long to larvae, pupae, and finally 2 - 4 mm adults
- A single female may lay several dozen eggs per day for three months or more
- Eggs laid on a host animal may fall off and hatch just about anywhere the host has been
- The eggs usually hatch in 1 to 10 days, depending on temperature and humidity
Newly emerged larvae are:
- 1.5 mm long
- Sparsely covered with hairs
- Translucent white
- Avoid light
- Actively burrow deep into fibres of carpet or beneath organic debris
Larvae feed on organic debris found in their micro-environment but must also feed on adult flea faeces, which contains partially digested blood. Flea larvae undergo 2 moults over a period of 5 to 11 days or longer, during which they double in size. The larvae remain translucent white but appear to darken due to ingested blood in their digestive tract.
Flea larvae require 50% relative humidity or greater for survival. They survive best outdoors in shady, moist areas during warm months in moderate climates. Indoors, they do best in protected areas, such as within carpet fibers, beneath cushions of upholstered furniture, cracks in wood floors or pet bedding.
As the larvae progress through their third instar, they spin silk cocoons for pupation. The cocoons, which incorporate dirt, lint and other debris, are hard to detect and also protect pupae from pesticide penetration. The pupal stage averages about 7 to 14 days, but some pre-emerged adult fleas remain in the protective cocoon for as long as a year waiting for a host-presence stimulus to trigger emergence.
Stimuli can include vibrations, warmth, carbon dioxide and pressure. Emerging adults begin feeding once they have found a host, usually within seconds. They commonly mate while on the host within a matter of hours and the female can begin laying eggs within 48 hours. Adults usually remain on the host and may live for one to four weeks.
When attempting to identify flea species the white sock method may be helpful. Simply put on a pair of white socks, pulling them up over the cuffs of your trouser legs, and walk around the areas suspected of harboring fleas. Fleas will quickly jump onto the socks where they can be captured for identification.