Arctic Warbler

Photo by LeeDavis
Bempton Cliffs, England, September 2004

Phylloscopus borealis

Includes: Japanese Leaf Warbler; Kamchatka Leaf Warbler

Identification

11cm.
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

Larger than both Willow and Greenish Warblers.

Distribution

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

Rare but increasing sightings on Fair Isle and the east coast of the UK in the autumn.

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

Taxonomy

Subspecies

Five subspecies are recognized^[1] (other authorities recognize from 3 to 7):

• P. b. borealis (talovka):

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

• P. b. transbaicalicus:

• Eastern Siberia to northern Mongolia; winters to south-eastern Asia

• P. b. xanthodryas:

• Sea of Okhotsk to Kamchatka Peninsula, Kuril Island, Hokkaido and Honshu

• P. b. hylebata:

• Eastern Amurland to northern Manchuria, Ussuriland and North Korea

• P. b. kennicotti:

• Western Alaska; winters in Philippines

A taxonomy thread^[2] in Birdforum suggests that Arctic warbler may end up being split into three species; the groupings differ minimally in plumage but more strongly in song. The three species probably would be Japanese Leaf Warbler (P. xanthodryas) in Japan except Hokkaido, Kamtchatka Leaf Warbler (P. examinandus) in southern Kamtchatka, Sakhalin, Hokkaido and the Kurile Islands, while all the rest would be found under the old name of Arctic Warbler which may become monotypic. Gill and Donsker have now accepted this split.

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. Clements, J. F., T. S. Schulenberg, M. J. Iliff, B.L. Sullivan, C. L. Wood, and D. Roberson. 2012. The eBird/Clements Checklist of Birds of the World. 6th ed., with updates to October 2012. Ithaca: Cornell Univ. Press. ISBN 978-0801445019. Spreadsheet available at http://www.birds.cornell.edu/clementschecklist/downloadable-clements-checklist
2. Taxonomy thread discussing Arctic Warbler read in June 2009
3. Wikipedia
4. BTO Bird Facts
5. Collins Field Guide 5th Edition
6. 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 22 November 2024 from https://www.birdforum.net/opus/Arctic_Warbler

External Links

Search for photos of Arctic Warbler in the gallery