MacGillivray's prion in New Zealand

[Colin Miskelly]

Kia ora koutou,

MacGillivray's prion was recently accepted by the Records Appraisal Committee as occurring in New Zealand, based on a Te Papa specimen found by Peter Bull on Ōtaki Beach in July 1954. This bird, and four recovered from Australian beaches and held in the South Australian Museum, all have bill measurements and mitochondrial DNA that indicate they came from Gough Island in the South Atlantic (and their identity as MacGillivray's prions, rather than possible hybrids with other prion species, is supported based on their nuclear DNA). Revelation that the five birds all came from Gough Island was an unexpected finding, as we were seeking to corroborate a GLS tracking study that revealed that four birds from the much smaller St Paul Island population (in the southern Indian Ocean) spent the 2018 winter in the Tasman Sea.

More information is in this Te Papa blog: https://blog.tepapa.govt.nz/2025/06/03/ ... ays-prion/

The paper describing the find was published in Emu - Austral Ornithology, but is hidden in plain sight behind a pay wall:

Miskelly, C.M.; Tennyson, A.J.D.; Horton, P.; Penck, M.; Ryan, P.G. Barbraud, C.; Delord, K.; Shepherd, L.D. 2025. Hidden in plain sight: DNA sequencing of museum specimens confirms the occurrence of MacGillivray’s prion (Pachyptila macgillivrayi) in Australia and New Zealand. Emu - Austral Ornithology https://doi.org/10.1080/01584197.2025.2490644

If you wish to access the paper, the blog contains a link to 50 free eprints.

So far, MacGillivray's prion is known from New Zealand from a single specimen that is now more than 70 years old. We are very interested to know if other birds from either population have reached New Zealand shores, or if they do so in future (e.g. during wrecks of related prion species). They are very difficult to distinguish from Salvin's prions and juvenile broad-billed prions. Unless or until other criteria are identified to separate these taxa, their identity will need to be confirmed using genetic methods. We are keen to receive whole specimens (of fresh beach-wrecks) or tissue samples of museum specimens that have bill measurements within the following limits:

Prions with bill widths of 16–20 mm could be MacGillivray's prion.
Those with bill lengths of 29–33 mm could be from St Paul Island.
Those with bill lengths of 33–36 mm could be from Gough Island.

Ngā mihi nui,
Colin

[Colin Miskelly]

More information and images are in this blog on the British Ornithologists' Union blogsite:

Hiding in plain sight: Genetic analyses of museum specimens expands two countries’ bird lists
https://bou.org.uk/blog-miskelly-macgillivrays-prions/

Ngā mihi,
Colin

[Colin Miskelly]

And an Australian perspective from the South Australian Museum blog site:

Age is no barrier to seabird breakthrough: https://www.samuseum.sa.gov.au/media/Ag ... eakthrough