A conservation project aimed at reviving Scotland’s rare medicinal leech population has welcomed its first babies.
Twenty leech hatchlings have emerged as part of a captive breeding initiative at the Highland Wildlife Park in Kincraig, near Aviemore. These young leeches are the offspring of adults collected from Dumfries and Galloway, one of the few locations in Scotland where the species is still found in the wild.
Once widespread, medicinal leeches saw a sharp decline during the 18th and 19th centuries due to their extensive use in medical treatments and the loss of wetland habitats. The Royal Zoological Society of Scotland (RZSS), which oversees the wildlife park, hopes these captive-bred leeches can eventually be released into suitable lochs to help boost wild populations.
The project is a collaboration with conservation charity Buglife. Dr. Helen Taylor, conservation program manager at RZSS, expressed her excitement about the recent hatchlings: “Seeing these baby leeches is incredibly exciting, especially as it’s more than we expected so early in the project.”
Buglife conservation director Craig Macadam also highlighted the species’ historical importance: “Medicinal leeches have a special place in our medical history, but they are now among Scotland’s rarest invertebrates. The success of this rearing program is vital for securing a future for them here.”
Medicinal leeches are the UK’s largest leech species, growing up to 20cm (8 inches) long. They have five pairs of eyes and a sucker armed with three jaws and about 100 tiny teeth.
These leeches feed on fish and frogs but can also attach themselves to larger animals, such as deer, sheep, and cattle, when they wade into water to drink. Medicinal leeches are a protected species in the UK, with populations recorded only in Dumfries and Galloway and parts of Argyll and Islay in the Inner Hebrides.
Historically, medicinal leeches were used in bloodletting treatments, where blood was drawn in the hope of curing various ailments. Today, farmed leeches are still used in medicine to help reduce blood clots and improve circulation. A medical leech farm currently operates in Wales.