The rare Marsh Fritillary butterfly has had a strong year in Northern Ireland, boosted by warm weather and long-term conservation work. Once widespread, the species declined sharply due to changes in farming and loss of its only food plant, Devil’s-bit Scabious.
Surveys by Butterfly Conservation show major increases in caterpillar nests on managed sites. One farm saw numbers rise from 24 to 53, another from 24 to 139, and a third from five to 27.
Conservation manager Rose Cremin stressed that while good weather helps, proper habitat management is essential. Volunteers and farmers work together each autumn to monitor larval webs, which can contain up to 100 caterpillars.
Because the Marsh Fritillary produces only one brood per year, it is highly vulnerable to habitat loss. Although the species has declined significantly over recent decades, this year’s results show that restoration efforts are paying off.
