That’s the conclusion of MOB, the environmental commission for Brussels and surroundings, which has been running Operation Chlorophylle since 2006. (The name has nothing to do with photosynthesis, as you might expect, but with the main character in a comic strip by the late Raymond Macherot.)

In 2008, MOB tallied three sightings of the dormouse in the park, which is something remarkable. Eliomys is commonly found in southern Europe as far as the Alps and Bavaria; but the forests of northern Germany are home to some, while in the Netherlands, where it could once be found all over Limburg, it’s practically extinct.

Schaarbeek must have something that agrees with it: in its latest tally, MOB counted no fewer than 15 dormice, thanks in large part to the nest boxes the Chlorophylle project set out, most of which, but not all, were colonised by birds.

The population growth, MOB says, is a vindication of the project, which now makes the garden dormouse a creature of regional interest for Brussels, given its threatened status elsewhere.

If you want to see one, you’ll need to go at night, as it’s nocturnal. You can recognise a dormouse by its black eye-patches, large ears and the white tassel on the end of its tail. But be careful: Dormice have been known to eat baby birds, as well as other mice. They are also fiercely territorial and will defend their patch against intruders. Each territory has a radius of 75 metres. The Walckiers park is only 300m at its widest point; there may be no place to hide.