The answer to 'why is my flea trails' is that you likely have a flea infestation in your home. Flea trails, or flea dirt, are the droppings left behind by fleas as they move around. This is a common sign of a flea problem, especially if you have pets or live in an area with a lot of wildlife.
Flea trails are tiny black or brown specks that are about the size of a poppy seed. They are often found in carpets, pet bedding, cracks and crevices, and other areas where fleas congregate. The trails indicate that fleas are actively reproducing and living in your home.