An unprecedented wave of WILSON'S STORM PETRELS

An unprecedented displacement of WILSON'S STORM PETRELS (Oceanodroma oceanicus) took place over the past weekend, involving up to 64 individuals. With a deep Atlantic depression fast moving towards NW Europe on 30 July and with two birds off Bridges of Ross (County Clare) on 29 July (Owen Foley) and a single from a Scilly pelagic NW of St Martin's on 31 July, expectations were high for the weekend.

Counties Clare and Kerry (SW Ireland) were lashed by strong NW winds whilst at the leading edge of the front, Cornwall and Pembrokeshire were met with very warm, moist SW winds. As a result, WILSON'S STORM PETRELS were somehow mixed up with this relatively unseasonal autumnal weather, with a staggering 27 individuals streaming past Bridges (Dermot Breen, Dave Fitzpatrick, Donal & Owen Foley, Dave McNamara, Finbarr McGabhainn, John N Murphy, et al) and a further 15 (no doubt including some of the former) off Brandon Point (County Kerry).

Whilst two showed well from a specially chartered fishing boat 8 miles NW of St Ives Island (Cornwall) (Brian Mellow, Royston Wilkins, Paul Freestone, et al), two more lingered beyond the Runnel Stone with 3 European Storm Petrels off Gwennap Head, Porthgwarra (Cornwall), from 0650-0945 hours (Russell Wynn, John Swann, et al) and another flew west past Strumble Head (Pembrokeshire) and with news filtering through, afternoon pelagics yielded at least 9 near the Seven Stones Reef off Scilly (Bob Flood et al) and a further 5 up to 20 miles NW of Padstow (Cornwall).

In days past, when seawatching was much in its infancy, finding just 1 Wilson's often involved looking at 3,000 or more European Storm Petrels but in this recent invasion, the ratio was surprisingly small, with Bridges only logging 300 pelagicus.

Amazingly, as quick as they appeared, subsequent visits to the same areas in the Western Approaches off Scilly in the following days failed to locate any, perhaps confirming that a large wave of feeding and migrating birds were forced to move eastwards to avoid the inclement weather and sea conditions.