Leeches are a type of segmented worm with a similar appearance to the common earthworm. There are over 700 species of leeches that have been identified and the majority of these are found in freshwater regions. Leeches are best known for attaching themselves to their food, including humans, with their strong jaws. However, not all leeches will bite and only a small number of species feed on people. Let’s find out what these small animals eat.
What do leeches eat?
Leeches feed on the blood of other organisms, which is an attribute known as hematophagy or by the common name bloodsucker. Most species of leeches eat small invertebrates, such as insects, and these are commonly eaten whole. When feeding on blood the leeches attach to the host, release an anesthetic (so the host cannot feel them) and secrete an enzyme (hirudin) into the blood stream to prevent the blood clotting. The leech will then feed until it cannot store anymore blood and it then detaches from the host to digest the meal. Not all leeches can bite and those that do not bite instead feed on decomposing organisms or open wounds in other animals, such as frogs, fish, birds and mammals.
Did you know?
Leeches can eat and store up to 5 times their bodyweight in blood.
Leeches were once used in medicine for a practice known as bloodletting. It was once thought that this kept the body in the correct balance. Leeches are still sometimes used in modern medicine in plastic or reconstructive surgery.
A leech can be removed from the skin by breaking the seal between the leeches sucker and the skin. Other methods are not recommended because they may cause the leech to regurgitate their stomach contents into the wound. Leeches sometimes carry disease, which means that the wound must be thoroughly cleaned after the leech has been detached. Bleeding may continue for some time after the leech has been removed because of the hirudin.