Mammals in the twentieth century

Of the 49 or so terrestrial mammals in Britain (bats excluded), 14 have increased strongly in range and numbers over the last 50 years, five or six have declined, and the status of the others is variable or uncertain. The increases largely indicate recovery from more ancient decclines due to persecution, while the declines reflect especially problems with introduced species (competitors or predators) and cahnges in land use. The biomass is overwhelmingly dominated by humans and domestic ungulates (97%), leaving little eological space for wild species, but there is scope to restore a little more balance by reintroducing long-extinct species.