The rare Marsh Fritillary butterfly has had a strong year in Northern Ireland, thanks to warm weather and long-term conservation work. Once widespread, the species declined sharply as traditional grassland habitats were lost.
Recent surveys show major increases in caterpillar nests on managed sites. One location saw numbers rise from 24 to 53, while another jumped from 24 to 139.
Butterfly Conservation says these gains highlight the importance of habitat restoration. The species relies entirely on one plant—Devil’s-bit Scabious—and depends on carefully managed grassland, often grazed by cattle.
Volunteers survey caterpillar webs each autumn to track population health. Because the Marsh Fritillary produces only one brood per year, it is highly vulnerable to habitat loss. Despite decades of decline, this year’s results show that conservation efforts are paying off.
