All at sea
Storm petrels, skuas and shearwaters: Mike Alibone rides the crests and braves the troughs of a successful Scilly pelagic weekend.
“Stormie in the slick!” The shout goes up as another European Storm Petrel swings into view above the waves behind the MV Sapphire, as it chugs further out into the south-western approaches of the Atlantic, 15 km off Scilly.
This is just one of many and part of the eclectic mix of seabirds I was fortunate to encounter during a ‘Birder Special’, four-day weekend of pelagic trips, organised and run by Scilly Pelagics in August this year. Founded in 2006, the organisation is managed by Bob Flood and Joe Pender to cater for the growing interest in seabirds and ocean wildlife found in Scillonian waters. In so doing, it has developed an enviable reputation for serving up uncommon, highly prized and soughtafter seabirds within British territorial waters.
For anyone simply aspiring to ‘get up close and personal’ with ocean wanderers, pelagics offer opportunities unrivalled by land-based seawatching, those embarking on them invariably being rewarded with astonishingly close views of birds and other, often breathtaking, examples of marine life.
Maximising the chance
While it could be argued that much of this is down to chance, in the case of pelagics off Scilly, the odds can be favourably shortened by applying knowledge acquired through considerable experience over the years. This ultimately results in visits to productive areas to maximise connection with seabirds on any particular day. Weather conditions, ocean currents and upwellings generated by reefs are all factors constantly being taken into account. In the case of the last, nutrients and food items are brought to the surface, with Pol Bank, 5 km south-west of Bishop Rock and Seven Stones Reef, 14 km north-east of St Martin’s, being key locations, high on the agenda for visiting.
On day one, as we headed out in a south-easterly direction, over a relatively calm and serenely sunlit early evening sea, hopes were high for connecting with the target species: Wilson’s Storm Petrel. This bird was, until relatively recently, the stuff of dreams for the majority of birders who undertook both pelagics and land-based seawatches. Once considered a rarity by the British Birds Rarities Committee, it was removed from the list in 2006 as the number of UK records increased. Key to this were the early pelagics off Scilly exposing its true status as a regular, though scarce, autumn passage migrant off south-west England.
From the point at which we left the harbour at St Mary’s, the crew commenced chumming, a practice which ensures a steady trickle of food dropped, or thrown, from the stern of the vessel to draw in seabirds. In this instance, the provision of small, bitesized pieces of bread and mealworms is intended principally to attract gulls, which stay with the boat for the duration of the trip, following it back to port when it returns after having been up to 20 km out at sea.
While the gulls are not essentially the principal focus of the pelagic, the idea is that they act as a flag, attracting more seabirds to the area around the vessel. With at least 50 large gulls, including two Yellow-legged Gulls, in tow, it wasn’t long before the first Great Skua appeared, half-heartedly harrying the European Herring and Lesser Black-backed Gulls around the boat before heading off south-west. This was one of just a handful we were to see over the weekend, with one choosing to hang in the air only a few metres above the deck, offering stunning, point-blank views.
By now, several Northern Fulmars had arrived, appearing to take an interest in the mêlée. These were quickly joined by a small number of Northern Gannets of various ages, tagging along and taking a passing interest in the proceedings before breaking off and flying back out to sea.
Minutes later, there was a shout out for Grey Phalarope off the port side – initially sitting on the sea’s surface, riding the waves before moving up beyond the bow and then away across
the ocean. This was the first Grey Phalarope of the autumn for the Scilly pelagic season.
Know the lingo
Getting acquainted with basic nautical terminology is a must on board ship. Knowing the difference between bow and stern, port and starboard, as well as o’clock – this being used after a number to indicate direction – can mean the difference between getting onto a fastmoving ‘fly-by’ and missing it altogether.
Luckily, this was not the case with our next encounter. A Sooty Shearwater, the first of a dozen logged over the weekend, passed the boat at a distance far enough out for it to remain in view for the best part of half a minute but close enough to appreciate the plumage detail. Breeding principally in southern Chile, the Falkland Islands, south-east Australia and New Zealand, one can only marvel at the fact that Atlanticbased post-breeders undertake an amazing 30,000 km figure-of-eight transequatorial migration, which brings them north to the UK, before returning south to their breeding grounds in October.
After reaching a position approximately 8 km south-east of the islands, the engine was cut and some serious chumming commenced. It was time to hold your nose as a large, frozen block of mushed up pilchards, mealworms and fish oil was extracted from a heavy-duty, plastic container, placed in a net and hung over the bow to trail in the sea as the boat slowly drifted. The result is a gradual release of the oily contents to produce a broad ‘slick’, which extends up to 200 m from the boat. This is readily visible as it changes the water’s surface, making it smoother and more reflective, an effect caused largely by the fish oil component. The ‘scent’ from the chum can be detected by seabirds from enormous distances and it wasn’t long before a number of European Storm Petrels were drawn in. Suddenly, there was a shout from the port side: “Wilson’s!”
The bird whipped by exceptionally fast, refusing to give itself up for anything approaching satisfactory viewing. But all was not lost. Minutes later, another passed the boat on the same side, this time much closer, flashing its trademark yellow webbed feet before it, too, disappeared into the waves. Two more eventually gave themselves up that evening, much to the delight of those on board.
Over the following three days, we notched up a further 14 Wilson’s Storm Petrels, many at close range, in what has transpired to be a record year for the species, with an incredible 20 consecutive days’ run contributing to a total of 124 by the end of August. This contrasts with the typical 30 to 60 per year, while the poorest annual total is only four. Despite its UK scarcity, the world population is believed to be approximately 50 million pairs, breeding on the islands and coasts of the Antarctic continent and moving into the North Atlantic during the northern summer, when it is commonly encountered off the coast of North America.
Rough conditions
The weather became less settled during the following three days and under a frequently leaden sky, the sea was rougher, waves became higher and troughs deeper, a combination which required the three dozen or so birders aboard the Sapphire to exercise some balance or to find some form of support while standing up on deck. It also became increasingly difficult to hold optical equipment steady. Fortunately, I was in a good place, having the
latest Kite Optics APC 12x42 imagestabilised binocular to hand, enabling prolonged and uninterrupted steady observation, in these conditions making a tremendous improvement to viewing quality over and above conventional binoculars (see Birdwatch 343: 50-51 for a full review of this binocular).
It was in such conditions we encountered our first Great Shearwater of the trip. For me, this species has always been by far the most attractive of the shearwaters, this individual providing us with awesome, almost ‘reach out and touch’ views. This was followed by four more during the course of the weekend. Undertaking a mammoth migration as far north as Greenland and Baffin Island, this is another shearwater from the South Atlantic, with an island breeding range restricted to Tristan da Cunha, Gough Island and the Falklands.
It was not, however, the rarest shearwater of the weekend. That accolade fell to the one dark-morph Balearic Shearwater we encountered on the final evening. It remained in the slick only briefly, before continuing to head west until out of sight. This species offers cause for concern and for immediate conservation measures to be implemented. Population modelling has indicated that Balearic Shearwater will be extinct in 60 years’ time, primarily as a result of threats from fishery bycatch, but also from those posed by over-exploitation of prey by fisheries, introduced predators and pollution.
But if it’s serious vagrants you’re after, these short-range Scilly Pelagic trips have notched up a number seabird firsts for Britain, including Fea’s Petrel, Scopoli’s Shearwater, Band-rumped Storm Petrel and Britain’s first and to date only accepted at-sea record of Swinhoe’s Storm Petrel.
If the above has not whetted your appetite for pelagic adventure, then
I can only offer the following quote from birding entrepreneur and intrepid seabirder Hadoram Shirihai as a closing remark: “Remember, no two days with the sea are the same, every day has the potential for further discovery …” ■
Acknowledgements
I would like to thank Bob Flood for sharing his considerable knowledge and for providing much useful discussion and comments, and Robert Bullock, Glenn Overington, Joe Pender and Graham Thomas for providing highly illustrative photographs, all of which were taken on Scilly pelagics.