Forest Dormouse (Dryomys nitedula)

You might just as well say,’ added the Dormouse, who seemed to be talking in his sleep, that “I breathe when I sleep” is the same thing as “I sleep when I breathe”!’  Lewis Carrol, Alice’s Adventures in Wonderland.

This is a rodent that is widely found throughout eastern Europe, the Balkan region, and Central Asia.   The creature looks a bit like a squirrel with a gray fluffy tail nearly as long as its body.  The upper body parts are grayish-brown while underparts are a contrasting yellowish-white.  The animal sports a broad black splotch around the eye that extends to the ear.  They weigh 0.6 – 1.1 ounces with a body 3-5 inches long with a similar tail length. 

These dormice spend a lot of time in the trees, where they are often confused for a small squirrel.  They prefer dense forests and form nests in the tops of the lower tree branches or in dense shrubs.  Nests are typically more 3-20 feet above the ground and are 6 – 10 inches in diameter.  The inside of the nest is made cozy with a lining of moss and bark.

Depending upon the climate where they live, dormice may hibernate during the cooler season.  Forest dormice in the northern part of their range will hibernate from October to April.  They will sit on their back legs and curl up in a ball in their shelter and their body temperature will drop from around 36° C to 5° C.    

The name of the common dormouse may have its origin in the Anglo-French for “tending to be dormant” (dormeur– sleeper) – for their habit to hibernate – with the second element confused for “mouse”.

In the warmer part of the range dormice will take advantage of the longer season and produce two litters; northern climate dormice only have one litter per year.  Gestation is about four weeks with four or five young typical.  The young leave the nest in five weeks and will be sexually mature the following Spring.  In the wild they will live for about 5 years.

Forest dormouse range

These animals are quite opportunistic in their diet choices and in the Spring this includes tender parts of green plants, buds, nestling birds, and a variety of invertebrates.  As the season progresses, they will move on to what is available including fruits, nuts, and seeds.  In turn they are preyed upon by wildcats, owls, stone martens, and pine martens. 

In one study in western Russia, the species was found in higher densities in oak forest compared to hornbeam-beech forests but body weights were similar, indicating the oak habitat could support a greater population density.  Interestingly, the researchers surmised that this had to do with a greater availability of nest sites in the oak forest structure compared to the hornbeam-beech forest and not food availability.  This is a good example of the complexity of ecological parameters – food is often not the limiting factor.

Apparently they are quite the aggressive little furball.  In captivity they will allow a human to pet them, but try and hold them and you’ll get a sample of their incisors into your finger.  If you poke them while they are asleep they are known to leap high, spit, and hiss.  Looks playful

While it spends most of its time in trees, the dormouse is nocturnal in contrast to true squirrels, which are diurnal, so that should help in determining which is which. 

Quite a few years ago we spend a month in Greece, mostly on the Peloponnese peninsula.  We took a cog railway to visit the small town of Kalavryta in the mountains, most notable as the scene of Greek massacre at the hands of the Nazis in 1943 where almost 700 people were killed.

The railway travels through a narrow limestone gorge to reach the pastoral small town.  We spent a couple days here, mostly just wandering around the small town and local trails.  On our second day we were in our second story room with a large oak tree just outside the window.  It was dusk and suddenly this rodent-type creature scurried across a branch and stopped a foot from the window. 

What is that thing? I thought.  Its nose was too pointed to be a squirrel but I couldn’t think of anything else.  It bolted away, leaving me wondering.  It wasn’t until we returned to the states when I was able to run through the possibilities did I figure out it was a forest dormouse.  There is no equivalent in North America, other than maybe a woodrat, but these are distinctly different.  So I consider it a lucky chance encounter.

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