The garage was given a tidy up the other day. In a corner, tucked away against one wall, on top of a box was a neat, spherical mouse’s nest made of straw. The straw had come from a big bag of it standing in one corner, so wasn't brought in from outside.
Whole nest with a lime for comparison.
The nest is a puzzle. It doesn’t look like a typical wood mouse (Apodemus sylvaticus) nest, often an underground burrow. Nor does it look like a house mouse (Mus musculus) nest; those generally have a lot more chewed up paper and leaves in them and the grassy bits are smaller. It also lacks the distinctive smell of the house mouse – in fact, it didn’t smell of anything at all.
Split and chewed stems
Looking at it, the nest is about 15cm across with a distinct opening on one side; the straw stems of the outer layers appeared to have been split and chewed, whilst the stuff on the inside was much finer.
It wasn’t attached to anything (hanging wires or bamboo canes, for example) but tucked into a corner, on top of a box and just under 1m from the floor. No smell, no droppings, nut shells or cherry stones nearby and no debris inside the nest. From all that I’ve been able to find, it would seem to have been built by either a harvest mouse (Micromys minutus) or a dormouse (Muscardinus avellanarius). There are some good sized gardens around here, plus a school with its own grounds and the town is rural-ish, so there is probably a fairly good variety of wildlife, but a garage seems an unlikely spot for either of them.
What do you think? What kind of mouse could have built this nest?
A possible harvest mouse nest
Picture of a dormouse nest on this page