Britain's endangered willow tit needs vast area to thrive, research finds

Under 3,000 pairs survive, which each require 7 ha to prosper, with ex-industrial sites ideal for breeding

The willow tit, one of Britain's smallest and most endangered birds, requires a surprisingly large area of wild land to thrive, according to research.

Less than 3,000 pairs of the bird survive, mainly on brownfield sites in former coal mining areas, making it the fastest declining resident species, with numbers plummeting by 94% since 1970.