One man's dedication to recording the amazing moths of Meirionnydd

August 15, 2025

One man's dedication to recording the amazing moths of Meirionnydd

On Rennie Telford's forefinger squats what he describes as "a moth that looks more like a twig than a twig does!" Called a Buff-tip, its camouflage - which resembles a broken silver birch twig when its wings are folded - is one of the most remarkable in the insect kingdom.

In fact, says Rennie, moths are particularly adept at looking like inanimate or inedible objects when at rest. "There's a beautiful autumn moth called Merveille du Jour, which is really colourful when seen up close - a lovely greenish blue, speckled with white flecks - but when it lands on a lichen-covered tree, it disappears as if by magic so perfectly does it merge into its surroundings."

This is because most moths are nocturnal, so are therefore most vulnerable to predators during the day as they hide away waiting for the light to fade.

Most nights, high up in the hills above Friog, Rennie humanely captures dozens - sometimes hundreds - of moths, in order to record them for the National Moth Recording Scheme (NMRS). Several of the species he temporarily entraps are found only in this part of Wales. The following day, once he's carefully identified and counted them, he sets them free.

On June 29th, for example, Rennie caught 219 moths in his bucket-style trap that uses a light source to attract the insects. Inside egg boxes (which he puts inside the trap to give the moths places to shelter) were 67 different varieties, 11 of which were new for the year.

So far in 2025, Rennie has recorded 256 species of moth, "and we're only just over halfway through the year. It's the best year so far since I started doing this a decade ago. Last year I only recorded 302 species."

The information Rennie collects is sent to the County Moth Recorder of Vice-County 48 - which covers the historic boundaries of Meirionnydd - and the data is used to map the distributions of all macro-moth species and assess their trends over time. Ultimately, Rennie's recordings are published in the Atlas of Britain and Ireland's Larger Moths.

Through talks he's given and magazine articles he's written, Rennie has helped to dispel the bad press moths tend to receive, especially when compared to butterflies (both belong to the order of winged insects called Lepidoptera).

Moths are beautiful, he enthuses. "People might say, 'oh, moths eat your clothes', but in fact there are only two species that do that - out of more than 2,500 species of micro- and macro-moths that you find in Britain."

The beauty of moths: a Blood-vein that Rennie caught recently

There are also far more species of moth in the UK than there are butterflies, which number only 60.

With so many species of moth, identifying them can be tricky. Many - especially micro-moths - look very similar. "Sometimes you can't even tell by looking through a microscope," says Rennie, "so the only way to be sure is to dissect them. But I would never do that, as I don't want to harm any of the moths I record."

Moths come in all shapes and sizes. One of the quirkiest-looking is the Scorched Wing, which Rennie jokingly calls "Oooh er, missus" because at rests it resembles male genitalia! Some don't even look like moths: the Red-tipped Clearwing, which Rennie has recorded only once, looks more like a fly.

A Scorched Wing (or "Oooh er, missus") moth

So far this year, Rennie has recorded one rare species: an Ashworth's Rustic (with black and grey wings), which is only found in a small area of VC48 - "a hot-spot for them is the hills above Fairbourne and the higher reaches of Cader Idris". Last year his trap picked up a Clifden Nonpareil, a large and impressively beautiful moth found mainly on the south coast of England.

In fact, this is one of the trends he's noticed over the past ten years - that moths once found only in the south of Britain are now being discovered much further north.

"There's definitely been an increase in species that only used to be found in the south of England that are gradually moving further and further north, which shows that the temperatures are warming up. And a lot of moths are now turning up earlier in the year, too," he observes. "There are also certain species that seem to be in decline, almost certainly due to habitat loss."

Growing up in Somerset, Rennie was fascinated from a young age by wildlife in general and birds and bugs in particular.

"I hated sport at school, so when we played cricket I'd be sent to field on the outer edges of the pitch, and there were many times I was absorbed by a caterpillar or another bug as the ball came hurtling towards me!"

When Rennie and his artist wife Marion moved to Wales in 2000, after falling in love with the Fairbourne area whilst on camping holidays, Rennie went to work at the Centre for Alternative Technology (CAT) as an all-round handyman/eco cabins caretaker. One day, a youngster who was staying spotted a chaffinch on the fence and asked him what it was. "It dawned on me that a lot of people don't know what's around them in Nature, and that you don't have to go far to find lots of fascinating creatures."

Rennie remembers one lad, called Roland, being especially indifferent to the CAT experience - until he saw a beetle open its wing cases, unfurl its wings and fly off. "His mouth gaped, his eyes opened wide and he exclaimed: 'Look, it can fly - and it keeps its wings in a backpack!' Four years later I had a Christmas card from him, in which he mentioned the beetle - and told me he'd gone on to study biology!"

Rennie's ability to help young people engage with the natural world led to him writing a "nature corner" slot in the daily staff email, "which sort of took off; people would look forward to their morning emails." This, in turn, led to him giving talks, first to CAT staff and then to visitors. And he thoroughly enjoyed it.

"As a kid, I'd devour books on birds and Nature, but a lot of them were a bit po-faced, and it wasn't until I read Gerald Durrell's books that I realised you could use humour to talk about the animal world. So I started using it more and more in my talks and writing."

Soon after retiring from CAT, Rennie's wife fell ill, and two years later he suffered a minor heart attack that left him with residual tiredness. "Up until then, I'd enjoyed walking in the hills, looking at birds, so I couldn't do that so much anymore. As the years went on, Marion's health declined further and it became increasingly difficult for me to get out."

So Rennie turned his hand to writing articles for community magazine Sibrydion and, on the back of that, giving talks to local groups. And then someone lent him a moth trap.

"The first time I put it out, there were a few moths in it the next morning. Then I really started getting into it. I couldn't get out into Nature - but Nature was coming to me!"

As Rennie points out, it's not always the "stars" of the animal world that are the most fascinating. "When I started writing for the magazine, initially I thought I should talk about impressive animals and birds, such as red kites, but in fact the article that generated the most interest was about ticks! Yes, ticks are horrible - even I don't like them - but they have there most incredible life cycle."

Since Marion died last year, Rennie - now 78 - has had more time to devote to moths. Does he get a sense of making a difference to the future of the natural world?

"People sometimes ask what's the point of recording moths. At first, it was just something I enjoyed doing, but now I feel I'm actually doing something worthwhile, even though my input is tiny. As the American naturalist E O Wilson said: If humans were to disappear from the Earth tomorrow, there would be a bit of a hiccup, but insects would carry on. If insects were to vanish, however, humans would die out within two or three years."

He turns again to the beauty of moths. "While we sleep, there are these jewels of the night flying around our gardens. For me, they're like old friends that keep returning."