After April’s soggy box check, it came as a relief to set out in the dry in May. The woods were decked out in their best – more species of wildflower than I can name, in all the colours of the rainbow. And the dormice were co-operating too.
The check got off to a good start – in one of the first boxes we checked one of the volunteers called my attention to a small pile of dead leaves at the bottom of the box. That immediately made me think that an apodemus mouse (wood mouse or yellow-necked mouse) had started to build a nest there. That’s not something to particularly get excited about – if an apodemus mouse is using a box, that means it’s one less box available for dormice. And, unlike dormice, they’re not house-proud. They happily urinate and defecate in their nests. And an apodemus mouse is much more likely to bite you than a dormouse is. (Having said that, I’ve never been bitten by an apodemus mouse, but have been bitten twice by dormice…)
So, when I came to have a look at the box, I wasn’t expecting much. There weren’t enough leaves for it to be a proper nest, and there was no structure to it. But I investigated it gently, and as one of the leaves from the top of the pile shifted, I caught a glimpse of gold – the gold of a dormouse, rather than the dull brown of an apodemus.
The dormouse was torpid, so it was an easy job to get the mouse out and weigh it. It was a 16g female, which is about usual for this time of year. We managed to weigh, sex and put the dormouse back in its unconventional nest without waking it, which is always satisfying.

Obviously it’s always a delight to find a dormouse. But this was particularly special, as it’s the first dormouse we’ve found in the new boxes we put up last year. It’s good to know that we work we put in then is now benefiting at least one little dormouse. And it’s also encouraging to know that dormice are active that side of the footpath.
Many of the boxes we checked had birds nests in – mostly bluetit nests, generally with eggs being incubated, although one nest had chicks. They seem to be a little behind compared to previous years. There are also more wren’s nests around this year. Wrens build lovely nests – loads of moss, with a big chamber, and they keep them clean (unlike bluetits). Dormice will quite often move in to these.
We found another dormouse somewhere we weren’t expecting to. At the last few checks a shrew has been using an old dormouse nest, which by now has broken down and got smelly. If it had been unoccupied this month, we’d have cleaned the box out. But a dormouse had moved back in – obviously too lazy to build its own nest. This was a 14g male, who was also torpid, but showed signs of waking, so we dealt with it as quickly as possible before returning it to the dilapidated nest. Hence the lack of photos of this dormouse.
Two of the nicer dormouse nests from previous checks had been taken over by bumblebees. As you probably know, bumblebees are having a tough time at the moment, so it’s hard to begrudge them a couple of nest boxes. But they do pose a hazard for whoever’s checking the nest box, as they are prepared to sting if disturbed. Luckily we escaped unscathed, and will tread cautiously round those boxes until the bees leave the nest (probably in a couple of months time – they go into hibernation even earlier than dormice!).
So, a successful box check this month. Further encouragement that dormice are using the whole box check area, and a reminder to never assume dormice aren’t present in an unlikely looking nest.