Sunday 12 July 2020

Shearwater Conundrums at The Bill 9th July 2020


Local birders watching and photographing a flock of Balearic Shearwaters assembled on the sea off the end of Portland Bill found, on examining images later, something that resulted in them wondering whether one of the birds photographed just might be a Yelkouan Shearwater, a species which has only been acceptably identified in British waters once before. One or two are claimed annually by seawatchers on the south and west coasts of England but the records are customarily rejected due to lack of detail which is unsurprising as the bird is flying by, often at distance and visible for no more than a couple of minutes at most.

The fact that this bird had been photographed and remained off Portland Bill all day, was seen well and the images stood up to close scrutiny, as well as being widely publicised, resulted in a major twitch ensuing on 8th July at 'The Bill' as Portland Bill is popularly known, for this would be the first twitchable Yelkouan Shearwater in Britain, ever.

Balearic Shearwaters, with which the Yelkouan Shearwater was associating, are themselves one of the world's most endangered birds with a population of around only 6000 individuals.They breed on the Balearic Islands and the south coast of France but constant building development in those areas, results in an inevitable loss of habitat and associated light pollution, cats, rats and everything else detrimental associated with human expansion has contributed to their ongoing decline. Losses at sea from oil pollution and getting caught in fishing nets only exacerbates the problem.

Balearic Shearwaters breed from February to June and then disperse around the Balearic Sea, the north east coast of Spain and Portugal but up to a third pass through the Straits of Gibralter and move north across the Bay of Biscay to feed around the south, west and east coasts of Britain and Ireland from July to September. They primarily feed along coasts and not out to sea hence the flock of around sixty to seventy birds feeding off the East Cliffs at The Bill. 

Yelkouan Shearwaters are closely related to Balearic Shearwaters and in fact were lumped with them as one species under the name Mediterranean Shearwater until the 1990's when a review of morphology and DNA resulted in them being declared two separate species. Yelkouan Shearwaters breed in the east and central parts of the Mediterranean and mainly winter in the Black Sea unlike the Balearic Shearwater that breeds in the western parts of the Mediterranean and moves west to winter along the Atlantic coast. However at least one mixed colony of Balearic and Yelkouan Shearwaters has been found breeding on Menorca. Could the proposed Yelkouan Shearwater off The Bill be a bird from the mixed colony that had moved north with the Balearics? 

So I now had the enticing prospect of seeing a new bird for my British List in the form of a Yelkouan Shearwater and the pleasure of also viewing a nice flock of another much rarer shearwater in the form of the Balearics. The irony that the Yelkouan Shearwater, although the rarer bird in Britain, was not in fact the rarer of the two species in world terms, with a population somewhere between 30,000 and 100,000 individuals was not lost on me

I rang Mark on Wednesday and we agreed to meet at The Bill first thing the next morning. First thing next morning meant a three hour drive from my Oxfordshire home to The Bill and required my getting up at 2am to be there an hour after dawn at 5am.

Somewhat blearily on Thursday I set off into the night, with a strong but surprisingly warm northwest wind blowing and the roads wet from overnight rain. With little traffic on the roads apart from slow moving lorries I made good time, passing the many laybys on the A34 that these days are noticeably full of huge trucks, the drivers asleep in their cabs. I reflected on what that kind of life must be like and how fortunate I was to no longer have to work. The sky began to lighten as I crossed the New Forest heading towards Ringwood and then later, approaching Weymouth a mist descended bringing gentle rain and low visibility. My spirits sank but as I descended into Weymouth I found myself below the cloud and feeling more confident about my prospects at The Bill. It takes approximately thirty minutes to get from Weymouth to Portland Bill and requires ascending up onto the top of the promontory and soon I was back in cloud again. Cue more despondency but descending down to The Bill, I again left the cloud and finally turned into the huge car park adjacent to the lighthouse. It was five thirty and I was one of only half a dozen cars in the vast open concrete space that comprises the car park.Where were all the other birders? Surely there would be more coming to see the first twitchable Yelkouan Shearwater in Britain?

It was well after dawn but the light was dull and grey, matching the concrete expanse I was parked on and outside the car it looked singularly uninviting. I sat in the car thankful to be able to sit with the engine off and not have to concentrate on any more driving. A period of reflection ensued as I gathered my frazzled wits. A rain squall spattered the windscreen, blown by a very fierce wind coming from straight off the nearby sea. I remained in the car until the rain passed, then got out to put on my wet weather clothing and get all my birding stuff ready. With these weather conditions it would be attritional standing on the cliff edge looking out to sea with no shelter apart from the huge obelisk at the very tip of The Bill.

I rang Mark and Les to see where they were and learned they were still on the M3 miles from The Bill and it would be over an hour before they reached me. There was no point in waiting for them and more to the point I had no excuse to remain in the car. I set off for the cliff edge, a few hundred metres distant. The wind was ferocious, whipping at my clothing and sudden short rain squalls hit my face. It was going to be tough going for sure. I got to the obelisk and cowered in the lee of it with just two other intrepid souls but the wind dementedly eddying around the obelisk still violently shook me and my scope, so it was extremely difficult to maintain my balance. I clung to the tripod trying to hold both myself and the scope steady.
The Obelisk
I looked out onto the heaving sea where two tide races violently collide and churn huge swelling waves into a maelstrom of roiling water. Holding onto the scope tripod I commenced scanning the sea. 


At first I saw nothing but huge seas but then eventually found the dark shapes of some shearwaters, alternately visible and then invisible as they disappeared in the huge wave troughs and then rode up on the crest of a wave. My heart sank. How on earth am I going to find a Yelkouan Shearwater in this? It's madness. You see a shearwater and before you can study it the waves consume it and down it goes into a trough and it seems an age before up it rises again.Then you start the process all over again and again and again!


Slowly my frustration and irritation subsided and I got into a rhythm and began the tedious process of trying to find the Yelkouan Shearwater. It took a long time as the shearwaters were slowly drifting out to sea but eventually they would fly back, closer to the cliff and so this process repeated itself time and time again. A small group of around twenty Balearics finally gave us hope as the last but one bird on the left end of the flock looked very good. Smaller and less dusky than a Balearic, appearing neater with a noticeable white breast, it bobbed and periodically disappeared with the others into wave troughs but every time it came up it looked more and more convincing. The visibility was still not good however and there was always the concern of it being a Manx Shearwater which, like the Yelkouan are smaller than a Balearic.The views needed to be more conclusive to be absolutely sure. I needed to see it in flight as if it was in wing moult it would almost definitely be the bird as Manx Shearwaters generally do not moult at this time of year, but there was little sign of that happening and all the while the vicious gusts of wind were shaking the scope making viewing constantly difficult. Oh for some shelter and a more placid vewing point! That however was not going to happen so I just had to get on with it.

Meanwhile Gannets, Razorbills, Guillemots and an endless processions of gulls were passing by or also sat on the sea but it was the shearwaters I needed to concentrate my tired eyes on.

Slowly the light improved and the wind notched down just a tad. Mark and Les arrived and I told them I was reasonably confident I had seen the Yelkouan Shearwater but the views in my opinion were not one hundred percent conclusive. By now there was a crowd of around sixty or seventy birders crammed on the cliff edge, everyone concentrating on the flock of shearwaters bouncing up and down on the heaving seas. A large flock of gulls had by now also congregated on the sea and it soon became apparent they were awaiting feeding opportunities as shoals of fish arrived off The Bill. 


Part of the crowd come to see the Yelkouan Shearwater
When a shoal arrived the gulls arose en masse from the sea in a wheeling, mewling whirl of white and grey and descended on the shoal of fish. This in turn stimulated the shearwaters, sitting on the sea a little further out, to fly in and join the feast, resulting in a milling mass of gulls and shearwaters either flying around or, in the shearwaters case, scudding and pattering across the surface of the sea with half open wings, like random leaves blown in the wind, ready to make shallow dives into the turbulent water. The shearwaters would rise from a dive and then fly up and around to resume diving on the moving shoal once more while the occasional Gannet rocketed down like a missile through their midst to hit the water with a resounding splash. It was exhilerating, chaotic and lasted but a few minutes.



The flock of gulls and shearwaters at 'The Bill' c Mark
It was a free for all, every bird for itself but it was in one of these brief melee's that we all saw a Yelkouan Shearwater. Cries of excitement rose among our ranks. 'There it is. It's flying right. It's on the water. It's flying. It's diving. It's coming straight towards us'. There came a constant running commentary from various disembodied voices around me and indeed it was coming towards us. I had it full on in my scope getting ever larger. Obviously paler brown, neater and slightly brighter than the surrounding Balearics and smaller, with to my mind a more delicate bill. Its wings were in heavy moult, the gaps showing much as in the photos from yesterday, its legs and feet protruding well beyond its tail. It wheeled and the white underwing revealed an indistinct dark bar across its axillaries.

I lost sight of it. as Les standing beside me inadvertently obscured my view. I could not pick it up again from the mass of birds. No matter, I now felt I had seen it well and conclusively and I relaxed. This was surely the bird that had been photographed yesterday but others considered it to be a different Yelkouan Shearwater from yesterday. So who knows? 

From then onwards there were frequent feeding frenzies as shoals of fish regularly arrived off The Bill and I saw the bird on most of these occasions, either flying, feeding or sat on the sea, often preening. After a while it became relatively routine to be able to pick it out amongst the Balearics but one also had to be ultra careful as there were now several  smart and clean looking Manx Shearwaters amongst the Balearics, not many but enough to cause confusion, which they did on a number of occasions as people called the wrong bird.

Probable Yelkouan Shearwater  c Mark

Balearic Shearwater c Mark

Balearic Shearwater c Mark
I did not bother to take any images. Frankly I was too tired and out of sorts. I really wanted to concentrate on the Yelkouan Shearwater and learn as much as I could about identifying it in the field or should I say at sea? Fortunately Mark had his huge lens and camera combo and did the necessary and has kindly leant me his images to illustrate this blog. For me it was hard enough keeping on the bird with my scope and bins without trying to pick it out with a camera lens as the constant movement of both birds and sea was bewildering.

As the morning progressed murmurs arose amongst my fellow birders that there were definitely two Yelkouan Shearwaters present today. I confess to being unsure but photos seemed to suggest there were two and I might have seen the two sitting side by side on the sea for one biref moment but they were lost to sight in a huge swell of sea. The crucial thing is that the few Manx Shearwaters present could and did look similar at distance when sat on the sea and in poor light but Manxies are generally not in wing moult at this time of year so any shearwater flying that was in wing moult could only be either a Balearic or Yelkouan. 

I guess it is now a wait to see what transpires and hopefully photos will prove the suppositions one way or the other. There was quite a lot of mis-identification going on during the morning and various birders were claiming to be viewing the bird when in fact they were palpably not. It's understandable considering the less than favourable viewing conditions and a lot of people were relying on others to spot the right bird for them. Before leaving for The Bill I had revised the identification features of Yelkouan Shearwaters, which in a book, in the quiet of a room, appear relatively straightforward and obvious but on getting to The Bill I found it was a whole different matter when presented with a highly mobile bird, in foul weather conditions, only giving fleeting views on a constantly moving sea at different ranges and in ever changing light.

The three of us eventually felt confident we had seen the right bird well. For me, the chance to make an in the field comparison with the few Manx Shearwaters present was highly instructive as was the comparison with the closely related Balearics. In the end I sat, drained from lack of sleep, the long drive to The Bill and seven hours of almost constant observation of shearwaters in very trying conditions. I went into a mental freefall, watching and enjoying the spectacle of the shearwaters feeding and resting on the sea. Enjoying myself as the crowd of birders slowly thinned. The light became progessively worse as a sea fret moved in and the lighthouse foghorn commenced its plaintive warning. The shearwaters became indistinct blurred shapes as they were now more distant on the receding tide. We called it a day at noon and went for a coffee.

Not quite finished we searched for a Lulworth Skipper.The conditions were just about hopeless but nevertheless Mark found one clinging for dear life to a Dwarf Thistle, as the wind whipped across the grass. None of us had knowingly seen a Lulworth Skipper before so it was a nice little cameo to end our day.

We can but hope the Yelkouan Shearwater(s) are accepted. 





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