Can Leeches Reproduce by Fragmentation?

There are 650 species of leech. Leeches that attach to animals and humans are of the Blunered species. They have strong suckers, which they attach to suck an animal's blood until they become engorged and drop off the animal. Leeches are found in ponds, lakes, springs, small streams and on land in jungle areas. Although fairly harmless, they can be a menace to drinking cattle and application of endon berries (Phytolacca dodecandra) in those waters helps to eliminate them.

Lifecycle

• Leeches reproduce in the spring, and baby leeches emerge from their cocoons in the summer. They live for a season if they survive the feeding habits of fish, turtles, ducks and birds. Leeches prefer shallow waters near the waterbed to avoid their enemies, but in doing so, they live in areas where humans and cattle congregate. Wading in or drinking from their infested waters frequently attracts the leeches to warm mammalian bodies where they attach themselves for dinner.

Reproduction

• Leeches have both male and female sexual organs. Leeches are not capable of regeneration by fragmentation, as are some worms. Leeches mate by intertwining their bodies and depositing sperm in each other's clitellar area. The sperm then make their way to the ovaries for fertilization. The clitellum of each leech produces a cocoon in which the fertilized eggs are placed. The cocoon is either buried in mud or attached to underwater objects. Some species of leech attach the cocoon to the parent bodies. Depending on the species, after several weeks or months, the baby leeches are born. Adult leeches generally pass away after they have reproduced once or twice.

Medicinal Uses

• Leeches have been used medicinally for centuries to remove blood from humans. In modern times the Hirudo leech is used for plastic and reconstructive surgery. This leech produces a blood anticoagulant (to reduce blood clots), a vasodilator (which increases blood circulation) and an anaesthetic (so the bite is painless) when it is attached to a patient. These properties fight against gangrene, remove excess blood in a region of the body and may be useful in the treatment of heart attacks and strokes.

How to Remove a Leech

• If a leech attaches itself to your body, the best way to remove it is to either allow it to drop off once it is sated or locate the oral sucker of the leech. Place your finger beside the sucker and dislodge the leech by pushing the sucker sideways using your fingernail. It is not recommended to use a match, salt or pull at the leech to remove it as these methods can result in an infection due to leech regurgitation into the wound. Clean the area and use a styptic pencil or bandage to stop the bleeding. Some itching may occur.