Family Petrels, Shearwaters (Procellariidae)

Endangered

MacGillivray’s Prion (Pachyptila macgillivrayi)


Taxonomy

French: Prion de MacGillivray German: MacGillivray-Entensturmvogel Spanish: Prión de MacGillivray
Taxonomy:

Prion vittatus macgillivrayi

Mathews

, 1912,

St. Paul’s in the Indian Ocean

.

Previously ascribed to P. vittata, and sometimes given full species status#R#R, but position had been considered intermediate between P. salvini and P. vittata#R. However, recent discovery that, along with P. vittata, another (narrow-billed) form of Pachyptila, in addition to P. salvini, breeds on Gough lead to renewed interest in the present taxon, because the ‘new’ S Atlantic population shows a strong degree of morphological congruence with P. macgillivrayi in S Indian Ocean. Given that on Gough the two forms of P. vittata breed assortatively and are spatially segregated, and that elsewhere two species of Pachyptila, showing comparable differences in bill widths, breed sympatrically at similarly offset times—P. belcheri with P. desolata and P. salvini with P. desolata in the Crozet Is—it seems reasonable to believe that two species are involved. Gough birds are provisionally accepted to involve macgillivrayi and, equally provisionally, this taxon is considered to merit specific status. Nevertheless, both assumptions require further testing, including molecularly. Monotypic.

Distribution:

S Indian Ocean, breeding on St Paul I (Roche Quille) and formerly on Amsterdam I.

Descriptive notes

25–28 cm; wingspan 57–58 cm. Typical Pachyptila having medium blue-grey upperparts and mainly white underparts, and is essentially identical to P. salvini... read more

Voice

No recordings are known; probably silent at sea, like other Pachyptila, while calls at... read more

Habitat

Marine, normally occurring offshore, except near colonies. Breeds on islands, usually in caves or... read more

Food and feeding

No published information, but feeding behaviour at least is likely to be extremely similar to that of P. salvini.

Breeding

Almost nothing known, although some previously published data from Gough attributed to P. vittata may in fact pertain to P.... read more

Movements

At-sea distribution more or less completely unknown, being complicated by virtual impossibility of... read more

Status and conservation

ENDANGERED. Tiny population in Indian Ocean is threatened by introduced rats and cats and deforestation, and this population is thought to number just 150–200 pairs or c. 540... read more

Recommended citation

Kirwan, G.M. (2018). MacGillivray’s Prion (Pachyptila macgillivrayi). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from https://www.hbw.com/node/1445422 on 18 January 2018).