Dartford warblers are non-migratory heathland specialists that suffered catastrophic mortality in the 1962-63 cold winter, requiring active heathland management.
Dartford warbler welfare is tightly linked to heathland quality and winter severity. Severe winters cause mass starvation. Wildfire destroys nests and may kill birds directly. Maintaining heathland structure through controlled burning and grazing management creates the diverse habitat that enables individual warblers to find food and shelter.