American Buff-bellied and Siberian Buff-bellied Pipits should be treated as separate species, according to new research.
Buff-bellied Pipit Anthus rubescens is found on both sides of the northern Pacific Ocean and is closely related to Rock Pipit and Water Pipit, with all three species having previously been considered conspecific.
Currently, there are two allopatric subspecies groups of Buff-bellied Pipit: rubescens and alticola in North America and japonicus in north-east Asia. Despite great similarities in their breeding plumages, most individuals can be assigned to one or the other subspecies group in non-breeding plumage.
A long-staying American Buff-bellied Pipit in Devon in 2022 (top) and a wintering Siberian Buff-bellied Pipit in the Netherlands earlier this year (Jonathan Clay / Eduard Sangster).
The new research, published in Zootaxa, analysed mitochondrial DNA (mtDNA) and a range of sound recordings from public databases. By comparing mtDNA and call divergence between American and Siberian Buff-bellied Pipits with similar values measured between long-recognised species pairs of pipits, the researchers concluded that the level of genetic and acoustic divergence between the two Buff-bellied Pipit subspecies groups is typical of species-level divergence in the genus Anthus.
As a result, they propose that Buff-bellied Pipit is split into two species: American Pipit Anthus rubescens and Siberian Pipit Anthus japonicus.
American Buff-bellied Pipit is a near-annual vagrant to Britain and Ireland, chiefly in western areas, with a slight increase in recent years (eight records are cited in the latest BBRC report for 2021).
There are no proven records of Siberian Buff-bellied Pipit in Britain, though in recent years individuals have reached south-east France (2019) and the Netherlands (2023). The closest regular wintering grounds are in the Caucasus and Middle East.
Reference
Alström, P, Coiffard, P, Crochet, P-A, Doniol-Valcroze, P, Dufour, P & Robb, M. 2023. Molecular and acoustic evidence support the species status of Anthus rubescens rubescens and Anthus [rubescens] japonicus. Zootaxa.
