Recent North Atlantic records of Swinhoe's Petrel (Oceanodroma monorhis)

At 1.15am on 19 July 1989, a large petrel was seen and heard calling as it circled the trapping area where British Storm Petrels were being tape-lured on Tynemouth pier, north-east England. It departed unidentified. However, on 23 July, a similar bird was attracted to the tape and trapped. In the hand, the ringers were astonished to find a storm petrel superficially resembling Leach's Petrel, but with an all-dark rump. The bird was ringed, measured and photographed before release. On 26 July, an unringed bird, identical to the first, was trapped.

At the time, no certain identification could be made, as there were no obvious candidates amongst birds likely to reach the UK, but research began into the possibilities...

In 1990, a third individual was trapped on 6 July. The same bird was re-caught in July every year for the next 4 years, i.e. 30 July 1991; 29 July 1992; 21, 28 and 29 July 1993 and 11, 23 and 25 July 1994. This provided the possibility to use DNA analysis to assist in the identification. In 1991, a blood sample was taken by Dr David Parkin. Analysis of cytochroime-b mitocondrial DNA sequences in comparison to samples taken from Swinhoe's Petrels in Russia and Korea finally proved that the bird was of this species, this particular individual being a female.

More details about the taxonomy of the species, which is sympatric with Leach's Petrel (Oceanodroma leucorhoa), are available from Sibley's sequence and in the Birdguides library. Some literature references are as follows:

1. James, P.C. & Robertson, H.A. (1985) "First record of Swinhoe's Storm-petrel Oceanodroma monorhis in the Atlantic Ocean", Ardea 73, pp. 105-106
2. Carruthers, M.P., Cubitt, M.G. & Hall, L. (1989) "The dark-rumped petrels in Tyne & Wear", Birding World 2, pp. 288-289
3. Bourne, W.R.P. (1990) "The first dark-rumped petrel", Birding World 3, p. 249
4. Bretagnolle, V., Carruthers, M., Cubitt, M., Bioret, F., & Cuillandre, J-P. (1991) "Six captures of a dark-rumped, fork-tailed storm-petrel in the northern Atlantic", Ibis 133, pp. 351-356
5. Cubitt, M. (1991) "The mystery petrels of Tyneside", Birding World 4, pp. 295-297
6. Cubitt, M., Carruthers, M. & Zino, F. (1992) "Unraveling the mystery of the Tyne Petrel", Birding World 5, pp. 438-442
7. Dawson, R. (1992) "Blood, sweat and petrels", Birding World 5, pp. 443-444
8. King, J. & Minguez, E. (1994) "Swinhoe's Petrel: The first Mediterranean record", Birding World 7, pp. 271-273
9. Cubitt, M. (1994) "The mystery dark-rumped storm-petrel", Birding 26, p. 125
10. Cubitt, M.G. (1995) "Swinhoe's Storm-petrels at Tynemouth: New to Britain and Ireland", British Birds 88, pp. 342-390
11. Brinkley, ES. (1995) "Dark-rumped storm-petrels in the North Atlantic", Birding 27, pp. 95-97
12. Bourne, W.R.P. & Simmons, K.E.L. (1997) "A dark-rumped Leach’s Storm-petrel in the South Atlantic", Sula 11, pp. 209-215
13. British Birds Rarity Committee Files (1997) "The Chalice petrel", British Birds 90, pp. 305-313
14. Force, M. (1997) "Comments on 'The Chalice petrel'", British Birds 90, pp. 339-342
15. Morrison, S. (1998) "All-dark petrels in the North Atlantic", British Birds 91, pp. 540-560
16. Bolton, M. (1998) "Swinhoe’s Storm-petrel ringed at Ponta de Almadena, Algarve, 27th June 1998", A Rocha Bird Observatory Report, 1998
17. O'Brian, M. Patteson, JB., Armistead, GL. & Pearce, GB. (1999) "Swinhoe's Storm-petrel: First North American photographic record", North American Birds 53(1), pp. 6-10
18. Palmer, P. (2000) "First for Britain and Ireland: 1600-1999", Arlequin Press

The species had been observed over a number of years on Selvagem Grande in the Madeiran Archipelago, where breeding has been suspected (see below). In addition to these records, further records have come from various parts of the North Atlantic in recent years, including Norway, Holland, France, Portugal, the Mediterranean coasts of Spain and Italy, as well as off the US east coast.

The origin of these birds is debated - vagrancy from the Indian Ocean round the Cape being one possibility and a small North Atlantic breeding population being another. In support of the latter is the fact that the first North Atlantic record, from 1983, was of a male on the nest of a Madeiran Petrel (see James & Robertson 1985); in 1988, a male was captured (Bretagnolle et al. 1991) and, in each year from 1993 to 1996, a female with a vascularised brood patch was regularly caught on a nest (Zino 1997). Bretagnolle (1991) suggests that there might be a breeding population on the Azores or Cape Verde Islands.

More information on European status is provided on Eurobirding and on international distribution on Avibase and Oceanwanderers:

• Swinhoe's Petrel on Eurobirding
• Swinhoe's Petrel on Avibase (includes worldwide distribution map)
• Swinhoe's Petrel Oceanwanderers

An exhausted bird at Eilat, Israel in January 1958 (Bourne, 1967) was the first record for in the Western Palearctic, and an obvious vagrant from the Indian Ocean. After the 1983 Maderia record, there been a further 16 confirmed records of Swinhoe’s Storm-petrel in the Western Palearctic, all trapped. In addition, Morrison (1998) documents 19 "dark-rumped" small Oceanodroma storm-petrels observed ‘at sea’ in the North Atlantic up to 1998 (though note that dark-rumped Leach's Petrel have also been identified by DNA analysis, so that any sight records must be uncertain). My own compilation of some of the more recent records (not necessarily all accepted yet) includes: