Leech
Leeches are commonly called bloodsuckers, as some species feed on the blood of people or animals.

What they look like:
Leeches are segmented, cylindrical worms with a sucker on each end, one being a mouth. In many forms, the mouth has three small jaws equipped with sharp teeth. Leeches can swim. They can also walk, which they do in a looping manner. Their body shape depends on whether their muscles are relaxed or taut.

Size:
From 7 mm up to 80 mm, when extended.

Where they live:
Leeches are found in warm, slow moving rivers or ponds. They prefer shallow water, and live under rocks and debris, or on plants, where they attach themselves to something solid.

What they eat:
Many Leeches feed on the blood of vertebrates such as amphibians, birds, reptiles, fish and mammals (including humans). Not all Leeches attach themselves to their food - some eat their prey whole!

What’s interesting about the Leech?

• Their salivary secretions contain hirudin, an anticoagulant (a substance that stops blood from thickening, or coagulating). This makes the blood runny, for easy sucking, rather like a milk shake as opposed to a thick shake!



• Some Leeches can survive up to 12 months after a blood meal because they can store lots of it in their body



• Leeches hibernate during droughts by burrowing into mud. They can survive a loss of nine-tenths of their body weight.



• Leeches are hermaphrodites - a single leech is both male and female.



• Medicinal leeches, once used by doctors to treat a variety of sicknesses, are used in some countries still.

Where they fit in:
> Phylum Annelida > Class Hirudinea > Family (Five families in Australia)