Arctic Warbler

P. b. borealis
Photo by LeeDavis
Bempton Cliffs, England, September 2004

Phylloscopus borealis

Identification

Length 12–13 cm (4¾-5 in), weight 7.5–15 g

• Olive-green above, greyish-white below. A single noticeable wing bar, and another less distinct, in fresh plumage (though sometimes one or both can be lost when feathers become worn). Long white supercillium and a broad dark eyestripe.
• Thick wedge-shaped bill, with a dark tip to the lower mandible.
• Flat forehead and slight peak to the hindcrown.
• Legs pinkish-brown.

Similar Species

See Japanese Leaf Warbler and Kamchatka Leaf Warbler for the complex identification of these recently split taxa. Can also be confused with Greenish Warbler, which is slightly smaller and has a different, disyllabic call.

Distribution

Breeds in Alaska, northern Asia, Scandinavia, and Siberia.

Migration mostly through eastern Asia, but rare but increasing sightings in western Europe, including the east coast of the UK, in the autumn.

Winters South-east Asia, Thailand, Burma and Indonesia.

Vagrant in northern Western Australia.

Taxonomy

Japanese Leaf Warbler P. xanthodryas and Kamchatka Leaf Warbler P. examinandus were formerly included in this species as additional subspecies.

Subspecies

Two^[1] to four^[2] subspecies are recognised:

• P. b. borealis:

• Scandinavia to Chukotsk Peninsula; winters to south-eastern China and Philippines.

• P. b. transbaicalicus:

• Southeastern Siberia to northern Mongolia; winters to south-eastern Asia. Included in P. b. borealis by IOC^[1].

• P. b. hylebata:

• Eastern Amurland to northern Manchuria, Ussuriland and North Korea. Included in P. b. borealis by IOC^[1].

• P. b. kennicotti:

• Western Alaska; winters in Philippines.

One other named subspecies, P. b. talovka, is generally treated as a synonym of P. b. borealis.

Habitat

Mixed coniferous, birch and other broadleaved woods, also in lush undergrowth near water. Most are in lowlands but the Kamtchatka breeds in higher elevation subalpine forests.

Behaviour

Very active bird, constantly flitting around in the tree canopy.

Flight

Dashing flight. Flicks wings and tail when at rest.

Breeding

The nest is on the ground in a low shrub.

Diet

The diet includes small arthropods, picked off vegetation or in flight.

Vocalisation

<flashmp3>Phylloscopus borealis (song).mp3</flashmp3>
Listen in an external program

References

1. Gill, F. and Donsker, D. (Eds). 2017. IOC World Bird Names (version 7.3). Available at http://www.worldbirdnames.org/.
2. Clements, J. F., T. S. Schulenberg, M. J. Iliff, D. Roberson, T. A. Fredericks, B. L. Sullivan, and C. L. Wood. 2018. The eBird/Clements checklist of birds of the world: v2018. Downloaded from http://www.birds.cornell.edu/clementschecklist/download/
3. Taxonomy thread discussing Arctic Warbler read in June 2009
4. Wikipedia
5. BTO Bird Facts
6. Collins Field Guide 5th Edition
7. Collins Bird Guide ISBN 0 00 219728 6

• List of references

Recommended Citation

• BirdForum Opus contributors. (2024) Arctic Warbler. In: BirdForum, the forum for wild birds and birding. Retrieved 23 November 2024 from https://www.birdforum.net/opus/Arctic_Warbler

External Links

Search for photos of Arctic Warbler in the gallery