Mammal recording was introduced to the BBS in 1995 with a view to help improve our knowledge of the distribution and population trends of some of our commoner mammals.
Compared with birds, the population trends of mammals are relatively poorly known. Even though mammal recording has always been a voluntary addition to the scheme, around 90% of BBS squares now hold mammal data.
Click here for more information.: Mammal monitoring | BTO – British Trust for Ornithology