Worm-like Insect Larva Bloodworms Bloodworms are the larva of the true midge. They are about 7.6 mm long when full-grown. They are blood red in colour because they have haemoglobin in their blood. Mammals, including people, have haemoglobin in their blood also. Haemoglobin holds much oxygen and therefore bloodworms can live in water that is low in oxygen.
Bloodworms eat vegetation found in the water.
They stick to plants, rocks and submerged twigs, often in large numbers. Some bloodworms live in tubes that they build from sediment, sand or small stones, and plant debris. They stick these bits together with a sticky secretion. Like the mosquito 'tumbler', the pupa stage of the true midge is active. The midge pupa is 0.48 cm long.