Tubifex worm

Sediment of lakes, rivers, and sewer systems, particularly in stagnant or polluted water with low oxygen.

Detritus, organic matter, and bacteria filtered from the sediment.

They live in tubes made of sediment and mucus. They exhibit a characteristic waving motion of their tails to absorb oxygen from the water while their heads remain buried.

Benefits: Essential part of the aquatic food web and used as live fish food. Risks: Can carry the parasite Myxobolus cerebralis (whirling disease) which is harmful to salmonid fish; they are also indicators of poor water quality.