David Beeson, late July 2021
My Apeman Wildlife camera has again been pointed at a peanut feeder just alongside our garage. This is adjacent to where I found two (rare) UK dormouse nests in November last year, and then recorded a pair on this feeder. Since that time brown rats found the feeder and started to dominate it – hence a new, highly protected feeder. Which is sad as I quite like rats, having kept two as pets, and the images on this feeder are less good. Yet yet rats dominated too much and had to be moved on.
The UK has a limited range of small mammals – the voles (long and short-tailed, the mice (yellow-necked, long-tailed, dormice and house mice) and shrews (common and pygmy). Edible dormice (introduced) are found in an area north of London but not around here. We also have brown rats and a remnant population of black rats in a few locations. Regrettably, we have no harvest mice here, although they occur with a couple of miles.
Dormice are found in Southern England, East Wales and a few other scattered locations, where they are being enhanced or re-introduced. They are deciduous woodland specialists, especially where there is a well-developed shrub layer. Mature hedgerows are also occupied, and ours is a conifer hedge (our neighbours’) enhanced with a diverse range of deciduous shrubs on our side. Ancient woodlands are ideal, but some dormice have been found living in coniferous areas.
I recently found a dead dormouse in a zone of pure oaks with no under layer, although a diverse range of plants was within 100m.
Dormice are almost exclusively nocturnal, and they can travel up to the tree canopy. Ours, so far, have been nocturnal and are content feeding from shelled walnuts, hamster food and peanuts. Droppings showed flowers were also being eaten. Our hedge has an array of food sources throughout the year: holly berries over winter through to ivy fruits in the autumn. There are climbing roses for hips, honeysuckle, cherry plums, damsons, apples, hawthorn berries and more. Dormice are poorly equipped to digest cellulose, so prefer softer vegetation and may avoid nuts.
Litter size is said to be between 2 – 9. Typically 4 or 5. They usually breed the year after being born. Life span, in the wild, at least 4 years. It is said that crows and magpies drop dormice they have caught, and that could have been the origin of the one I discovered under pure oak.
Dormice have special UK protection and handling them without a license is an offence – not that it was when I first caught one!
During the day long-tailed (bank) voles dominate the feeder, at night it becomes the realm of the mice – long-tailed, yellow-necked and dormice.
I have been checking this feeder since April, yet the dormice only reappeared in early July. Perhaps they had been feeding elsewhere since ending their hibernation or were very late in emerging. To date I have seen no signs of nests.
In summer dormouse adults: head and body 80 – 85 mm plus tail, 57 – 68 mm. Weight up to 25 g in pregnant females.
So, here are wildlife camera images; I regret not to John’s standard.
Wood mice range in size in summer: 80 – 100 mm plus tail, 70 – 95 mm. So considerably larger than the dormouse at maturity. Of course, young will be of various sizes. Yellow-necked have tails longer than their body, not so with the long-tailed mouse.
House mice are uniform grey, wood and yellow-necked brown in back colouration … not that I can see that on black-while images! House mice are largely creatures of urban environments as combine harvesters and ‘clean’ farming has decimated their food supplies in non-urban areas. Of 1536 small mice captured during a study in Wiltshire only 5 were house mice. The species is virtually never found in woodland areas. It may still occur in intensive poultry and pig units. One location that they do still occupy is off-shore islands. There, if other mice are not present, they may survive but they fail to cope with competition.
The camera has been moved higher to attempt to achieve more accurate size measurements.
A, wood mice. B, young dormice.
So, we have a family group of dormice adults and young, plus wood and yellow-necked mice. And, yes, given access we would see brown rats too.
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