Some friends of ours have a house in France and last year were bemoaning the fact that edible dormice (glis glis) had taken up residence. To someone who rarely sets foot outside of the UK, the thought of little, shy dormice being considered a pest seemed a little strange to me. However, it seems that these are not the small brown fellows much beloved of Autumnwatch (native hazel dormice), but bigger, greyer beasties.
So, why a blog post about these creatures? It is inspired by an article in the excellent, if somewhat scholarly, British Wildlife Magazine. What I didn’t realise was that there is a colony (or maybe more) of the creatures in Tring (Hertfordshire). They are also known as the fat dormouse – both names arising from the fact that they were kept as food by the Romans and were even carried in jars by Roman soldiers when on marches.
So, how did they get here? Well it certainly wasn’t under their own steam as studies on the Tring population have shown that they have really not extended their range very far at all. As in most cases it was human intervention that has resulted in the UK colonies. In this case, Lord Rothschild and an ‘accidental’ release at the beginning of the twentieth century.
So, the lowdown on edible dormice:
- They are quite a lot bigger than their native relatives and live for about seven years
- Whereas UK natives are brown, edible dormice are grey and about the size of a small squirrel
- They are nocturnal
- They hibernate underground from about the end of October to May
- They nest in holes in trees and are thought to form creches with the offspring of more than one female found in some nests
- The young aren’t born until July / August which gives them only two or three months to gain enough weight to hibernate
- Their favourite food is Beech mast – in years where it is likely that there will be a poor crop of Beech mast the dormice don’t breed
- It is thought that when there is a poor yield of Beech mast then the dormice are more likely to be found in nearby houses
So, why are they considered a pest? They do apparently strip bark from trees, however, the main problem with them seems to be the fact that they are often found in houses where they chew through wires and eat food stores. They are also doing rather well despite their limited range (mainly within 25 miles of Tring) – Natural England estimate that there are at least 10,000 of the animals in the UK.
They were recently listed as one of the top 10 problem invaders alongside mink and grey squirrels. There are certain methods that can legally be used for ‘dealing’ with these large eyed furry creatures, but it is also an offence to release these animals into the wild now, which is exactly what is thought to be behind their appearance outside of Tring. People had a problem with them, but couldn’t bring themselves to kill them, so took them far, far away and released them.
But, could you resist those big black eyes and grey coat – perhaps there are things that are too cute to kill? Still, that argument has never worked for seal pups though, has it?