Red squirrels live in dreys are made from sticks and lined with moss and leaves. Larger dreys are built to raise young in.

Red squirrels sleep in dreys. These are hollow balls of sticks and twigs that they line with leaves, moss and hair. Special breeding dreys are built to raise young in and these tend to be bigger than normal dreys. Dreys are built high in trees, often close to the trunk or in a fork, but sometimes, especially in areas of Scotland where red squirrels live alongside pine martens, near the end of a branch.

They’re often very small in relation to the size of a mature tree, so can be hard to spot. But once you’ve got your eye in, you should find them relatively easily. It’s best to search for dreys in winter, once the leaves have fallen from deciduous trees; at other times of year they will often be obscured by foliage.

If you spot a drey, you might want to spend some time searching around the base of trees in the vicinity, looking for the remains of squirrel feeding. It’s not always very easy to see from a distance if what you think is a drey is actually a drey, but if you find the remains of eaten cones or nuts that look fresh, you can be pretty certain that it is indeed a drey, and that it is currently being used by a squirrel.

Simply recording the presence of a drey can be useful, especially if seen alongside feeding remains.  If you’re interested in doing more with the data, you can carry out proper drey surveys, with the aim of gaining an estimate of the population density of squirrels living in the forest you’re observing.