The leaves have fallen, the ground is crisp, the woods are nearly silent… and the dormouse snoozes away for the winter! The Hazel Dormouse, Muscardinus avellanarius, is nocturnal, arboreal and very elusive. They are possibly one of the cutest animals I have ever set eyes on. The first time I saw one I was overwhelmed with how cute it was; with its big eyes and long fuzzy tail. I didn’t think there could be anything cuter until… I held my first dormouse in May 2023! This little guy was still in torpor. Torpor is similar to hibernation but is for a shorter period of time (usually lasting hours, rather than weeks or months). It is an adaption allowing animals to survive short harsh periods, often when there is reduced food availability.

Montgomeryshire Wildlife Trust (MWT) contribute to the National Dormouse Monitoring Programme (NDMP), which is run by People’s Trust for Endangered Species (PTES). This programme is over 25 years old and collates records from over 400 dormouse monitoring sites across the UK. Last year, 6,182 dormice were recorded from 414 sites! Dormouse boxes and tubes are used to monitor the mice, which they use to nest and sleep in. On five of our MWT nature reserves, we check our dormouse boxes 4 times a year, in May, June, September and October. We record the number of dormice, and other mammal species found, the sex, weight and age. You must have a licence to handle dormice, and thanks to People’s Postcode Lottery funding (awarded by Postcode Planet’s Trust) this is what I am training to do. PPL funds part of my role as Conservation Officer and allows me to help undertake important like this.

I started my training to become a licenced dormouse handler in May 2023, at our Dolforwyn Woods Nature Reserve. As I have stated above, the first dormouse I held was a sleepy, little male. I handled two other dormice that day, including one that had a white tip on its tail! This has been seen on a few individuals across the nature reserves. In May I visited Cwm y Wydden Nature Reserve;  although we found no dormice at this site, it was lovely to visit the wood in spring, hearing Wood Warbler sing and watching Beautiful Demoiselle damselflies flutter amongst the trees. I also visited Coed Pendugwm in May, my first time at this at the reserve. It was another beautiful spring morning, with Pied Flycatcher singing as the sun glistened through the newly emerging leaves, onto the many oak saplings sprouting from the woodland floor. We also checked the bird boxes whilst at this site too, one of which had 3 Brown Long-eared Bats.

In June I visited Dolforwyn Woods again, as well as Dyfnant Meadows. The latter is one of my favourite nature reserves. During our visit there, a Wood Warbler greeted us, and sang his heart out during most of the survey! We had a very late nesting Great Tit in one of the dormouse boxes (wildlife doesn’t follow the rules). We had wasps nesting in a few boxes, which we had to be wary of! Another highlight of this visit to Dyfnant Meadows was spotting my first Small Pearl-bordered Fritillary butterflies; there were lots of them flying around the wet meadow!

Fast forward a few months, and we enter late summer/early autumn and ready for the September surveys. The survey at Dolforwyn Woods this month will likely be my most memorable survey ever! We had several boxes of ‘exploding’ juvenile dormice. By exploding, I’m referring to the many young dormice that suddenly erupted out of the box - which we carefully opened – jumping onto my jacket and into my hair! Now that was an experience I won’t forget! Of course, all were safely retrieved and returned to their nest.

During this survey, we not only recorded the most dormice during a single survey since MWT began surveys in 2013, but we also had our first ever ‘pinks’. I gently put my fingers inside a dormouse nest and felt warmth, but no movement. I had a closer look and saw a tiny, jelly baby sized, pink, naked dormouse that was 0-6 days old! I carefully shut the box and put it back on the tree, and we quietly moved away so mum could return. We also found some rather small dormice in a nest at Dyfnant Meadows in September too. They were located in a box that you’d least expect to find dormice in, along a fence boundary near some bracken. I noticed a lovely woven bracken nest, which had 4 ‘grey-eyes-closed’ dormice nestled inside; these would have been 6-16 days old!

In October I took another trip back to Dolforwyn Woods, where we were still finding juvenile dormice-weighing as little as 4 grams. This is quite concerning as, in order to survive winter, they ideally need to be above 15 grams, so they didn’t have long left to put weight on!

Although it was amazing to see so many young dormice this autumn, it is a bit of a worry as we suspected that many were unlikely to put enough weight on before winter. This was seen across the country. At this stage we are unable to say what caused this, but the unstable weather throughout this summer could have been a possible factor.

My final survey this year was at Coed Pendugwm. We had a good mix of Hazel Dormice, Wood Mice and Yellow-necked Mice. One box I checked had a big, fat 54g male Yellow-necked Mouse! My colleague, Tammy, has been handling small mammals for over 20 years, and even she said this is the biggest she’s ever seen - he was a whopper! He will certainly have a strong chance of surviving winter!

What I love about the dormouse surveys is getting to see the same reserves at varying times of year. In May you hear the birds singing and holding their territories, alongside carpets of bluebells and wildflowers. Then in the autumn you get to see the leaves changing and lots of wonderful woodland fungi like the Amethyst Deceiver.

For more information about the National Dormouse Monitoring Programme, please visit https://ptes.org/campaigns/dormice/surveying-and-monitoring-hazel-dormice/national-dormouse-monitoring-programme-ndmp/