Meadow brown butterflies are among the most common UK butterflies but have declined with loss of grassland habitats, and their presence indicates surviving grassland biodiversity.
Meadow brown larvae dependent on native grasses in improved fertiliser-heavy grassland face starvation as coarse grasses replace fine native species. Adults in pesticide-treated areas experience impaired flight navigation and reproduction. The loss of unimproved grassland from agricultural landscapes represents a major welfare loss at population level for a species once ubiquitous across the British countryside.