Willow Warbler vs Greenish Warbler

In short

The Willow Warbler and Greenish Warbler can be challenging to differentiate, but key differences lie in their structure and vocalizations. The Willow Warbler typically has a longer primary projection and a more pronounced supercilium compared to the Greenish Warbler. Vocalizations also differ, with each species having distinct songs and calls.

Identification tips

• Check primary projection: Willow Warbler has a longer primary projection.
• Observe the supercilium: More pronounced in Willow Warbler.
• Listen for vocalizations: Each species has distinct songs and calls.

Plumage

The Willow Warbler generally has a more pronounced supercilium, while the Greenish Warbler may appear slightly greener overall. However, plumage can be variable and is not the most reliable feature for identification.

Voice

Vocalizations are a key differentiator: the Willow Warbler and Greenish Warbler have distinct songs and calls, which can be used to tell them apart in the field.