Meet the UK's only leech farmer supplying the NHS from a tiny farm near Swansea

• Report by ITV Wales journalist Dean Thomas-Welch

The small village of Hendy is a stone's throw from the M4 and just over ten miles from Swansea. At any one time it's also home for up to 100,000 blood-sucking leeches.

Carl Peters-Bond looks after the medicinal creatures and is the sole supplier to the NHS and accounts for nearly 70% of the medicinal leeches used worldwide. The tiny critters are being used in hospitals up and down the country as one of the most effective means to preserve blood loss.

Carl, manager at Biopharm Leeches, has worked at the plant for 30 years and he estimates that his meticulously bred leeches have saved thousands of limbs. The 47-year old joined the plant when he was just 17 and since then, he's spent countless days getting them ready to be sent out to clients - primarily the NHS in burns and plastic reconstructive surgery units.

"The day-to-day job is picking leeches," says Carl. "Big ones, smaller ones, fat ones, thin ones. Once the leeches are fed (once every few years) they are starved down. As they starve down we are continually sorting them until we get to that end stage which is a leech that has been starved for six to nine months with a nice empty gut and as sterile as we can make them."

As if Carl doesn't already have enough on his plate with the tens of thousands of leeches that depend on him - and the worldwide market of leech treatment - he's also taken the population of Hendy under his wing as the mayor.

Both Carl and his husband Chris are community councillors on Kidwelly Town Council. Last year they became Wales’ first same-sex married couple to be mayor and deputy mayor of a community council.

What occasion - or injury - requires one or more of the blood-sucking creatures to be attached to a person to heal them? An incredibly rare one according to Carl, the animals are now most commonly used to stem blood in the event a person has lost a limb or in some cases, to draw blood from hematoma's such as cauliflower ears.

While the need for leech treatment is still incredibly rare, there is enough to keep Carl and the small team at Biopharm - founded by Roy Sawyer from the USA - busy.

Carl sources leeches from all over the world, primarily southern Europe, and then breeds them at Biopharm to create two types called Hirudo verbana and Hirudo medicinalis, both known as medicinal leeches. Adding context to the specificity of Carl's niche, there are over 650 different types of breeds of leech worldwide.

Biopharm's owner, Dr Roy Sawyer lives yards from the Hendy plant but owns sites in Italy, Sweden, Finland, USA, South Africa, Ireland and Japan. Despite this, the NHS is still Biopharm's largest customer. Carl says that the UK takes almost half of the leeches they breed while the other half gets shipped worldwide.

While Carl's leeches are primarily used for medical care, with the increasing unpredictability of Welsh weather it seems as though they could have another role, as forecasters.

Due to their sensitivity to atmospheric pressure, Carl's leeches can often sense a storm coming long before the first rain drop has fallen. When the pressure lowers the leeches leave the water. On more than one occasion Carl has entered the farm to see thousands hanging from the ceiling.

Demand depending, some leeches can stay with Carl as long as six years. He says if looked after properly, it's not unusual for leeches to have a lifespan of 20 years. In that time, he said he hasn't been able to resist keeping some of the more interesting ones as pets. "Every now and again you'll get some freaky ones. Ones where you might do the final feed and you get ones that are twice as big as the others. We have kept a few of those."

While thoughts of using blood-sucking leeches to treat serious wounds conjure up images of middle-age medicine and witchery. Carl and his team at Biopharm are supplying hospitals up and down the country with one of the most effective means to preserve blood loss.