The dark green fritillary is Britain's most widespread large fritillary but faces habitat loss from scrub encroachment and loss of open grassland with violet plants.
Dark green fritillary larvae depend on violets growing in warm, open conditions. Scrub invasion following reduced grazing pressure or cessation of traditional management shades out violets and eliminates larval habitat within years. The butterfly's large territory requirements mean that habitat patches must exceed minimum viable size. Isolated small habitats cannot maintain populations long-term even if foodplants are present, making connectivity between grassland patches a welfare priority.