Commonly called "flea dirt," the feces on your pet left behind by fleas resemble bits of black pepper on your pet's skin, usually on the belly or tail. This flea dirt, composed mainly of the bloody meal the fleas enjoyed at your pet's expense, looks crackly and dark.
"Flea Dirt" Test
A first glance, you may not be able to distinguish flea dirt from regular old dirt your pet may have picked up playing outside.
To test the black specks on your pet, wet a cotton ball or paper towel and drop some of the "black pepper" on it. If it dissolves into a reddish-brown stain, it is very likely flea dirt and an indication of a flea problem for your pet.
It's smart to get into the habit of regularly checking for fleas and flea dirt on your pet. Brush your dog regularly and watch for any signs of fleas. Use a specialty flea comb to groom your dog's coat over a white paper towel to identify any flea dirt that may fall off. Also, inspect your pet's bed and bedding for signs of fleas.
Fleas flourish in warm, humid environments, but they can sit tight and wait for the right conditions for a couple of months. Fleas, especially females of reproductive age, consume large quantities of blood relative to their size and weight but can also survive for 100 days without a meal.
There are more than 2,000 species worldwide and females can lay up to 50 eggs per day, so it doesn't take long for one flea to turn into an infestation.
In addition to causing skin irritation, fleas can spread tapeworm and bacterial infections. If your pet constantly scratches, licks or chews one area, it might be an indication of fleas. Red, bumpy skin or patches of missing fur also warrant close investigation. You may not always see the little buggers, though, which grow to only about 1/8 inch at full size and dig deep into your pet's fur.
The multi-stage life cycle of a flea takes it from an egg to a larva, to a pupa, to an adult during the space of a few weeks in ideal conditions. In an infestation, it's common to find fleas in all stages of development. Giving your pet a simple flea bath or using a flea collar won't solve the problem. If you find a flea infestation on your pet, you need to attack it from several directions both on your pet and in your home, getting rid of the eggs and any adults.
For more information about beating a flea infestation, check out how to get rid of fleas.