About the Leech
Phylum Annelida, Class Hirudinea
Leeches are closely related to the earthworm. Leeches are most famous for their habit of sucking blood. There are over 650 species of leeches around the world, including some very large varieties reaching nearly half a meter in length! Here in British Columbia, however, all leeches are much smaller. They are an important food source for BC fish, although not so important as several of the insects.
What does the Leech look
like? Most of us have found out the hard way what a leech looks like! They have the general appearance of a fat, flattened worm with a tapering tail, ranging in colour from dark brown to black. They are usually a few centimeters long, but they may get up 15 centimeters when stretched out. Fish prefer to eat the smaller ones. When leeches swim, they undulate like a snake, only they do it up and down instead of side to side.
Where does the Leech live?
You can usually guess where leeches are living by the look of the water - they prefer shallow, dark water with lots of organic cover, like lily pads, which provide both food and shelter. Swampy areas are very popular leech hangouts.
The leech is a successful organism, and different types of leeches can be found almost everywhere in the world. They are common throughout British Columbia. There are 650 species of leeches found world-wide.
What is the life cycle of the Leech?
Leeches do not breed, because there are no female and male leeches.Click here to see the life cycle of a leech. Leeches are hermaphroditic, which means that they have both male and female characteristics and can produce offspring without mating. A single leech produces its own egg mass, which it attaches to an object under the surface of the water.
Although blood-sucking makes leeches seem quite carnivorous, they are mostly scavengers that eat the remains of dead insects and animals. They do also hunt insect larvae, snails and scuds. And they'll try to eat you, if they get the chance!
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