A fox in your garden? This is valuable information for the new Mammal Atlas of Brussels. 15 years after the last mammal atlas, Environment Brussels launches a new count of wild mammals living in Brussels. Nature changes constantly. Species like the stone marten and fox are on the rise, while others are strongly decreasing. The Mammal Atlas of Brussels shows on a map of Brussels where each mammal can be found. The last atlas dates from 2001. Environment Brussels, Natuurpunt and Natagora are now working on an update. To do so, they need your help! Have you seen a wild mammal (fox, hedgehog, rabbit, squirrel…) in a park, in your garden, on the street or in the forest? Report it on bru.waarnemingen.be or install the app on your smartphone. Based on these numbers, nature conservators can decide which animals are doing fine in nature and which need more protection or specific measures. Or also: which invasive species are a threat to other animals. This allows them to interfere when needed, both in the Sonian Forest and in other places.