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Leeches: Are They Really So Menancing?

Leeches: Are They Really So Menancing?

Many of our clients complain when they notice leeches in their ponds. The complaints are based on fear, but are they really justified? In the following article we will clarify the role of leeches in the aquatic ecosystem and learn about some of the advantages of having leeches in you pond. You`ll see, they really aren`t so terrifying! In total on Earth there exists close to 700 different species of leeches. All are carnivores but not all are haematophages (who are nourished by blood), many only eat worms, mollusks, insect larvae, and othe little organisms that populate the aquatic environment. Of those that enjoy blood, few enjoy human blood. In Canada, only one leech specie will chase your baby toe in the water : Macrobdella decors, or the medicinal leech of North America. Other leech species that feed on blood will choose frogs, snails, turtles, ducks over your tender flesh anyday. In Europe there are many species of bloodsuckers that prefer human blood. The most famous of these being Hirudo medicinalis which is now close to extinction but was once used widely in medical practices across Europe for treating many human ailments.


Since human blood is not always easy to find (few of us stroll in the water for the simple pleasure of feeding our friends (Macrobdella decors), this last evolutionary period brought frogs to thrive in our ponds. Frogs are the second favourite food for our leech friend. We generally find frogs in many water environments today, calm waters either warm or cold are normally homes to many species of frogs. Better than baiting leeches with bottled contraptions of rotting meat, consider going at the source of the problem by reducing (in a food chain sort of way) the leech population. Back to the frogs. If frogs are abundant, leeches will be too. Reduce frogs, reduce leeches.


Who eats frogs you ask?, why small mouthed bass eat frogs and tadpoles and they are suited to warmer pond water. Before you leap to the natural conclusion about fragile frog populations, introducing a few bass into your pond won`t eliminate all frogs, nor all leeches, it will simply help control a problem situation. And BBQ bass tastes great! Leeches are a wonder of nature that deserve our admiration. To avoid attracting our attention and for efficient latching, the leeche inject us at the precise moment of attachment, with an anesthetic and an anticoagulant. Even though they do not transport any disease, care (cleaning and covering site) must be taken after the leech detaches, since blood can continue to flow for up to 10 hours afterward. Isn`t that amazing! So what are you to do when a hungry leech attatches onto your leg? Don`t panic! If you are patient, you can let the leech take breakfast (it never over eats!) then it will detach itself as quietly as can be, and go and hide at the bottom of the pond for weeks or months. Remember, you won`t feel any pain from the leech, only a heat sensation at the dinner site. The pain comes when you try to rip off the leech from your skin. If you cannot wait for Macrobdella decors to finish eating, carefully dislodge it with the odour of a burning cigarette or sprinkle salt on it.


Leeches are not detested by everyone. Their analgesic, anesthetic, and anticoagulant virtues have made many micro-surgeons happy. To such a point that a company in England specialises in the commercialization of these little critters. So just remember, there is only one kind of leech in all of Canada that wants your blood, if it finds you it won`t hurt, in fact it is inviting you to become a part of its food chain. Just stock your pond with small mouthed bass, and eventually you`ll get your blood back! Happy pondering!