Adult Willow Warbler identification

Willow Warbler

Phylloscopus trochilus
Olive coloured upper parts
Pale legs and bill
Buff white to pale yellow underside
Similar Species
Chiffchaff
Mobile bird identification
Bird Field Guide
Play call/song
Northern breeders are more brown and white than southern counterparts
Chiffchaff
More brown, less yellow
Sings from high perch
Clearer eye ring
Blackish legs
Distinctive call
Downward bob of tail
Wood Warbler
Wood Warbler
Distinctive green back
Yellow breast
Yellow eye stripe
Brownish wings
Long, often drooped wing tips
Distinctive song and singing posture
Bonelli's warbler
Bonelli's Warbler (Rare)
Whiter underside
Plainer head
Grey brown legs
Faint pale line over eye
Likes upland conifers
Yellow rump in flight
Garden Warbler
Garden Warbler
Mostly pale buff brown
Short thick bill
Large dark eye
Slower heavy mover
No eye stripe
Eats berries
Juvenile or Adult in Autumn plumage
The juvenile and adult in autumn plumage are very similar, the underside and eye stripe are much more primrose yellow than the adult in spring and summer plumage.
Willow Warbler or Chiffchaff?
Icterine warbler
Icterine Warbler (Rare)
Broad orange-pink bill
Pale lemon underside
Grey legs
Faint pale line over eye
Large head
Long square tail
Melodious Warbler
Melodious Warbler (Rare)
Dark wings
Large dark eye/pale face
Grey brown legs
Similar to Icterine
Long round wings in flight
Upper parts green
Compare willow warbler and chiffchaff heads
Willow Warbler (left), Chiffchaff (right): Compare head shape and eyestripe
Distribution:
Very common and widespread summer visitor to Northern Europe and the UK. Can be found even in the far North of Scotland.
Habitat:
Frequenting scrub, hedges, orchards, and woodland. Can even be found in small wind blown bushes of highland areas.
Notes:
One of the UK's most widespread summer visitors, almost any area of broad leaf scrub or woodland will provide a suitable breeding habitat. Plumage gets progressively duller the further North the bird breeds, but is generally brighter than the Chiffchaff. The Willow Warbler will often catch insects by hovering like a Flycatcher. The best way to distinguish between Chiffchaff and Willow Warbler is by song.
Siberian Chiffchaff
Siberian Chiffchaff (Rare)
No yellow except underwing
Light buff eye stripe
Buff breast and sides
Warm buff behind eye
Winter visitor to UK
Warbler Menu
Distinctive long yellowish eye stripe
Greenish wing panel with long wings
Slightly mottled ear coverts
Thanks to: www.flickr.com/photos/rainbirder/ (Modified)
Willow Warbler body shape
Typical view of a Willow Warbler, note the sleek body shape, prominent eye stripe, pale bill and clean bright underside.

This bird also shows the slightly mottled ear coverts and the partially open tail indicative of the Willow Warbler.
Thanks to: www.flickr.com/photos/sussexbirder/ (Modified)
Willow Warbler Juvenile or Autumn plumage
Thanks to: www.flickr.com/photos/gails_pictures/ (Modified)
Chiffchaff wing length
Willow Warblers wing length
Thanks to: www.flickr.com/photos/sussexbirder/ (Modified)
Thanks to: www.flickr.com/photos/ferranp/ (Modified)
Willow Warbler (left), Chiffchaff (right): Note the difference in wing lengths and wing posture, the Willow Warblers primary feathers are much longer.
Willow Warbler Chiffchaff
Eye stripe Long/yellow Short/pale
Body shape sleek dumpy
Wing length Long Short
Tail bobbing Infrequent Always
Leg colour Pale Blackish
Wing panel Greenish Uniform
Ear coverts Mottled Plain
Eye ring Faint Distinct
Head shape Flat Round
Order: Passeriformes

Family: Phylloscopidae

Genus: Phyllosccopus

Species: P.trochilus
Adult Male and Female (Spring)