Monday, 21 October 2013

Dormouse update: Tenants wanted

...must be small, fuzzy and with a fluffy ginger tail.

Sliding-top Dormouse box: unlike bird boxes, the entrance hole is on the side which rests against the tree trunk, discouraging larger species or predators from using the boxes.

After carrying out regular box checks this year at Gatwick, we are yet to get a glimpse of the sneaky Hazel Dormouse (Muscardinus avellanarius). All the signs are there - a good woodland understory, including all their favourite food plants and even an old nest was found. Earlier this year, only a month after installing new boxes, we found bits of honeysuckle had been dragged inside (a typical dormouse behaviour), but alas, the weather suddenly turned cold again and there was no more activity. Pretty frustrating!

Equivalent to Hazel Dormouse graffiti: I waz 'ere... but not for long! 

On the left: a small grassy Harvest Mouse nest. On the right: larger Hazel Dormouse nest largely made up of stripped honeysuckle bark

Dormice are a protected species, but it is difficult to know how these small mammals are really faring as they are quite elusive, turning up in some odd places and in certain years seem scarcer than in others. Early in September I attended a dormouse ecology course with the Sussex Wildlife Trust to hear the latest science and thinking on these vexing little... critters.

Box checking in the woodlands in Crawley, West Sussex

Course tutor Laurie demonstrating how to 'bag up' a box containing a potential nest

The course was attended by an enthusiastic bunch of environmentalists, keen naturalists or people simply wanting to get involved in monitoring local Dormouse populations and the better management of woodland habitats. We had a bright and charming course tutor in Laurie who has a lot of hands-on experience with these and many other wee mammals. 

Bag 'o Dormouse - the weight and general health of each individual is recorded

This nest contained very new dormouse babies called 'pinkies', which are just visible in the centre. We only took a quick glance and then the box was placed back on the tree to minimise disturbance.

My highlight of the day was seeing a Dormouse run up a tree, showing off some brilliant arboreal acrobactics. There is a surprising amount to know about this superb little mammal, too much to sum up here and as I don't want to give away all the secrets from the course, here is a selection of the stranger dormousey facts we have learned:

1. There are many species of Dormouse - the Hazel Dormouse is the only one native to the UK
2. Adult females sometimes pool their young together in creches, possibly so that they can take it in turns to go out foraging. 
3. They do not just eat hazel nuts (which are seasonal and they don't bother storing), they also tuck into various flowers, pollen, nectar, fruit, aphids, caterpillars and teacakes*
4. They are descended from one of the most ancient rodent families
5. When handling dormice (under supervision of a qualified handler) it is advisable to roll up your sleeves
6. There are few reports of people being bitten by dormice, except for one unfortunate PhD student I know who must be finding particularly irritable ones.

* one of these facts might not be verified

(Muscardinus avellanarius) the Hazel Dormouse. 
In latin the word dormir means 'to sleep'


I used to be a bit cynical about how much small mammals could tell us, but I now see that by putting in a decent survey effort they can give an indication of the current condition of our woodlands for other wildlife. The next step in Gatwick's dormouse work is to carry out some Hazel coppicing and to increase our survey effort by installing more boxes. You can find out more about these and other UK small mammals here: http://www.mammal.org.uk/species_hub