New subspecies of Bartailed Godwit described

SCIENTISTS have recommended that a newly described breeding population of Bar-tailed Godwit is recognised as a subspecies.

Previously, Bar-tailed Godwits breeding in west and central Siberia were treated as a sole subspecies, taymyrensis. However, in a paper recently published in Ibis, Roeland

Bom and his colleagues at the Global Flyway Network argue that taymyrensis consists of two subspecies. Those wintering in the Middle East (and presumably also East Africa) should be recognised as a separate subspecies, yamalensis, on the basis of migratory behaviour, breeding area and morphology.

The team attached solarpowered tags to Bar-tailed Godwits in Oman, West Africa and the Wadden Sea. Data provided showed birds using the western route to breeding grounds on and around the Taymyr Peninsula, while those using the eastern route via the Middle East spent summer on the northern West Siberian Plain.

The two groups differed significantly in body size and shape, and also in the timing of both northward and southward migrations. However, they were not genetically differentiated, indicating that the phenotypic differences arose either very recently or without current reproductive isolation.

The team propose that those birds on the West Siberian Plain and migrating to the Middle

East should be recognised as a distinct subspecies, yamalensis, to those breeding on the Taymyr Peninsula and migrating to West Africa ( taymyrensis).