Rare leech found in Dumfries and Galloway
The Medicinal Leech (Hirudo medicinalis) is only known to be found in two other areas of Scotland
Last updated 23rd Nov 2023
A rare leech that used to be used for medical purposes has been found in Dumfries and Galloway by a local naturalist.
The sighting came from local naturalist, Bob Merritt, and follows unverified records from 2005 and 2008.
Buglife confirmed the presence of the Medicinal Leech in three ponds near Carrick Shore on the Solway coast, as part of the Scotland-wide conservation programme, Species on the Edge.
Medicinal leeches are one of the UK’s largest leeches as they can grow up to 20cm long. They are usually found in freshwater habitats such as lochs, ponds and lakes.
They are only known to be in 3 areas of Scotland. However, they used to be widespread before the overharvesting of them for use in medicine in the 18th and 19th century.
It is now illegal in the UK to use these leeches for medical purposes, but the pollution of the water has also really affected the populations of these leeches.
"An important place in medical history"
Buglife Conservation Director, Craig Macadam, said: “Medicinal Leeches have an important place in our medical history but are now one of the rarest invertebrates in Scotland.
“The discovery of three new sites for this species in Dumfries and Galloway is incredibly important and gives us hope that further sites are discovered for this incredible species in the future.”
There is going to be a new captive breeding programme created in Scotland to try and keep the leeches from going extinct.
Fiona Strachan, Species on the Edge Programme Manager with NatureScot said “These records from one of the Species on the Edge project areas are really exciting and, alongside the captive breeding programme, bode well for a more promising future for the Medicinal Leech.”
Sally Morris Species on the Edge Conservation Officer said:
“Historically, Medicinal Leeches were used for bloodletting. The idea was to balance out the four 'bodily humours' - blood, phlegm, black bile and yellow bile.
“It was thought that balance between these humours was needed to remain healthy and an imbalance could cause disease. They were used for a range of ailments including headaches, gout and brain disorders.”
Species is strictly protected in the UK
The Medicinal Leech that is strictly protected in the UK is no longer used in medicine. However, other species of medicinal leech such as Hirudo verbana are used in medicine.
Now there is a better understanding of how leeches can be used effectively in medicine such as their saliva being used as an anticoagulant that prevents blood clots and improves blood flow.
Leeches can be used in reconstructive surgery and cardiovascular disease. For example, in reconstructive surgery, tissues grafts or reattached tissue may have issues with blood circulation which could cause the tissue to be lost. By using leeches on that tissue, blood flow is encouraged back to the area and relieves blood congestion, aiding healing and reducing the chance of that tissue being lost.