First recorded

Willow warblers are migratory birds. They are summer visitors to the UK. Nature's Calendar monitors how early or late willow warblers arrive in the UK in spring.

In a location that you monitor regularly (at least once a week), record the date that you first see a live, active willow warbler after their winter absence. This is usually from March/April.

Available historic data: we have very good records from 1891-1999 (5575 records)