At present, the English names generally attributed to breeding populations of the Band-rumped Storm-petrel complex are unsatisfactory in that they do not offer an uncomplicated, unambiguous and non-overlapping solution. This is further complicated by the fact that many described forms are not recognised by global taxonomic lists, and several distinct populations globally are not formally described to science at all but likely represent cryptic species; some of these have been assigned vernacular names by birders (see e.g. Howell & Zufelt 2019).

Historically, all taxa were recognised as a single, monotypic species, internationally known as Band-rumped Storm-petrel but, in Britain, known as Madeiran Storm-petrel (despite the species’ range extending well beyond Madeira). 

Two populations – those breeding in Cape Verde and those breeding in the summer on the Azores – are now widely recognised as species in their own right: Cape Verde Storm-petrel Hydrobates jabejabe and Monteiro’s Storm-petrel H. monteiroi, respectively. At present, however, both IOC (Gill et al. 2024) and eBird/Clements (Clements et al. 2023) recognise all other populations globally as being part of a single, widespread, monotypic species: Band-rumped Storm-petrel H. castro. 

Within the Western Palearctic, two temporally separated forms of Band-rumped Storm-petrels occur: a summer-breeding population and a winter-breeding population. Much of their Macaronesian breeding range overlaps spatially, with birds even utilising the same nesting burrows, but breeding of the two forms is separated temporally. If these two forms are given (sub)specific status, the summer-breeding birds will take the name Hydrobates [castro] castro. Birds of this form are frequently referred to using the English name ‘Madeiran Storm-petrel’ (e.g. Robb et al. 2008, Howell & Zufelt 2019). The winter-breeding birds, which are not formally described scientifically, have been given the widely adopted English name ‘Grant’s Storm-petrel’ (Robb et al. 2008). 

Image

Identification criteria for birds away from their breeding colonies is still in its infancy and many birds seen in the field need to be left unidentified to species or population level. Consequently, all but one of the British records to date have been accepted as ‘Band-rumped/Monteiro’s/Cape Verde Storm-petrel’ (see e.g. Bacon et al. 2023). Recently, however, the first confirmed record of Band-rumped Storm-petrel – a winter-breeding Grant’s Storm-petrel from the Canary Islands – has been accepted onto the British List (Bacon et al. in prep.; see also https://bou.org.uk/british-list/changes-to-the-british-list-13-aug-2024). Breaking from the convention used elsewhere, but maintaining consistency with the species name traditionally used in British English, BOURC choose to use the species name ‘Madeiran Petrel’ when adopting the species onto the British List.

With all of this in mind, and in an attempt to future-proof ourselves from likely further taxonomic changes, we wanted to make it clear which names British Birds is using for the various groups, species and forms in the Western Palearctic. This nomenclature is used in this month’s N&c and this paper. For a wider overview of other forms globally, we recommend Howell & Zufelt (2019). As a reminder, BB follows IOC taxonomy, and thus only three (currently monotypic) species are currently recognised.

Band-rumped/Monteiro’s/Cape Verde Storm-petrel Hydrobates castro/monteiroi/jabejabe
Used when the identification cannot be resolved to species or population level; includes all forms of Band-rumped Storm-petrel as well as Monteiro’s and Cape Verde Storm-petrel. For clarity, even if it is slightly cumbersome, British Birds will always use this format for unidentified birds and will avoid potentially confusing phrases such as ‘Band-rumped Storm-petrel complex’ or ‘Band-rumped Storm-petrel senu lato’.

Band-rumped Storm-petrel Hydrobates castro
Used to refer to the single species, including all of its (described and undescribed) forms. 

‘Madeiran Storm-petrel’ Hydrobates [castro] castro
Used only for summer-breeding birds in Macaronesia.

‘Grant’s Storm-petrel’ H. [castro] undescribed
Used only for winter-breeding birds in Macaronesia. 

‘Madeiran/Grant’s Storm-petrel’ H. [c.] castro/H. [c.] undescribed
Used in the (rare) situation where a bird can be assigned to one of the Macaronesian-breeding forms of Band-rumped Storm-petrel and where other populations and forms (e.g. vagrants from the Pacific) can be excluded, but where the bird cannot be assigned to either the summer- or winter-breeding Macaronesian population. 

Monteiro’s Storm-petrel Hydrobates monteiroi

Cape Verde Storm-petrel Hydrobates jabejabe

References

Bacon, L., French, P., & the Rarities Committee. 2023. Report on rare birds in Great Britain in 2022. Brit. Birds 116: 546–602.

—, —, & — In prep. Report on rare birds in Great Britain in 2023. Brit. Birds.

Clements, J. F., et al. 2023. The eBird/Clements Checklist of Birds of the World (v2023). www.birds.cornell.edu/clementschecklist 

Gill, F., Donsker, D., & Rasmussen, P. (eds.) 2024. IOC World Bird List (v14.2). www.worldbirdnames.org

Howell, S. N. G., & Zufelt, K. Oceanic Birds of the World: a photo guide. Princeton University Press, Princeton.

Robb, M., Mullarney, K., & The Sound Approach. 2008. Petrels Night and Day. The Sound Approach, Poole.

Stephen Menzie, Editor