The brimstone, one of Britain's longest-lived butterflies, depends on buckthorn and alder buckthorn shrubs that are being lost from hedgerows and woodland edges.
Brimstone butterflies with no nearby buckthorn cannot complete their life cycle. The loss of buckthorn from hedgerows through intensive management or replacement with conifers removes essential breeding habitat. Hibernating adults roosting in ivy and evergreen shrubs are vulnerable to disturbance and loss of hibernation sites. As one of the earliest spring butterflies, brimstones play a disproportionate role in early season pollination — welfare losses affect both the insect and dependent plant communities.