Dormice; rare, or just elusive?

I have been reading a very interesting and thought-provoking book! 'Living with Dormice' by Sue Eden challenges the accepted wisdom that the Hazel Dormouse (Muscardinus avellanarius) is a rare woodland denizen, rather that they are a common, if elusive, rodent. Whilst her work is based very much in Dorset, it rings true with my growing experience of this gorgeous creature here in mid-Wales.

One area which seems to have been generally overlooked is the relationship which the dormouse has with other rodent species, particularly the Wood Mouse and Yellow-necked Mouse. Sue tells us that, in her studies, she has found very few dormice in her boxes in years when these other mouse species are abundant and vice versa.

This morning, I have been out once again with Nick Young from Natural Resources Wales, helping him check 50 boxes in a woodland near Forge. Last time I was there I marveled at the number of boxes occupied by dormice, but this time was even better! I will never forget seeing a bag of five very active dormice in constant motion! Nor will I forget my first dormouse bite from one angry mother, which, whilst a shock, was nowhere near as painful as that delivered by a Wood Mouse! In all, we had ten healthy dormice in the 50 boxes and a good proportion of the rest contained empty nests. Compared to my monitoring at Coed Pendugwm Nature Reserve, where all year only one box has been occupied (out of 100!), this is astounding and got me thinking.

I asked Nick whether he had ever had other mouse species in his boxes and following a check through his notebook, he confirmed that he hadn't. At Coed Pendugwm, I get at least one Wood Mouse during every visit and once I have had a Yellow-necked Mouse too. The latter species has never been recorded further West than Coed Pendugwm (in Montgomeryshire), so its absence and the low numbers of Wood Mice in the Forge wood could go some way to explain the good numbers of dormice in boxes there.

Thanks very much to Sue Eden for further opening my eyes to the fascinating world of the Common Dormouse. I would recommend that anyone with an interest in this species read Sue's book.