The subalpine warbler is a classic “split bird” with birders having recorded “subalpine warbler” in the past, the now split created new species for their lists. The formal separation between eastern and western subalpine warbler was accepted by the IOC World Bird List in May 2020, however, the groundwork was laid earlier.
Researchers had been arguing since the late 1990s and early 2000s that the “subalpine warbler complex” contained multiple species with Lars Svensson’s influential 2013 paper proposed a three-way split into eastern, western and Moltoni’s. A comprehensive genetic study published in 2020 finally convinced the major authorities to adopt the split formally.
Before the split, almost all birds were simply recorded as “subalpine warbler”, and many older birds can’t now be assigned safely to species. So, there is no completely clean total for Britain by species. What we do have are the birds that have been confidently assigned - usually through DNA, calls, photos and detailed field notes.
A major 2024 review of vagrant subalpine warblers in northwest Europe examined 70 genetically analysed birds, most from Britain, and this gave a pretty good picture of the relative occurrence in the UK - western slightly commoner than eastern, with Moltoni’s much scarcer. Historically, Britain had well over 100 accepted “subalpine warbler” records before the split with one BBRC review noting 103 accepted records just in 2000–2004 under the old treatment. The interesting thing is that many British birders originally assumed most UK birds would prove to be western birds from Iberia and France, but the DNA work showed eastern birds, especially the Balkan form, are actually extremely regular in Britain.
In the UK, western subalpine warbler is currently thought to be slightly more common overall than eastern, but much closer in number than birders once expected. Before DNA and call analysis became routine, lots of those birds would probably have been assumed to be western. In practical birding terms, if a subalpine warbler is found in Britain, the western form is still the statistically safer bet, but eastern is common enough that you genuinely have to consider it carefully.
With all this said, in Britain they are a scarce migrant, so seeing one is a good rarity to add to the list. Also, they’re genuinely beautiful little warblers: smart grey males with brick-red throats and crisp white moustachial stripes. They have smooth blue-grey to slate-grey head and mantle, usually slightly colder-toned than western birds. They also have a reddish orbital ring that can look quite vivid in good light, much like our own Dartford warbler.
A bird found at Beachy Head has been identified by observers as a male eastern subalpine warbler, and specifically it appears to fit the eastern Balkan form. It was first reported on 12 May and has stayed unusually well for a subalpine warbler, helped by singing regularly and feeding in a consistent circuit around Cow Gap. Descriptions have mentioned: a strong white moustachial stripe, cold grey upperparts, an extensive reddish throat, and persistent singing/calling - apparently often the clinching feature for easterns.
Kev @kev07713 had already been fortunate enough to see a western form, so this bird would add another member of the subalpine warbler complex to his list. I’d never seen any subalpine warbler before, so not only would it be a lifer, it would also be my first of this group of warblers. That made the decision to head down and see the bird an easy one.
With it being Kev’s turn to drive, we set off towards a parking spot he’d identified - a slightly longer walk perhaps, but supposedly a much easier one. After a quick comfort stop and some breakfast on the way, we got closer to the coast before eventually pulling in beside the kiosk and the free parking - well, I am Scottish after all. There had already been a positive update on BirdGuides and so it was likely the bird would still be there when we got to Cow Gap.
We arrived and immediately saw the climb waiting for us up towards the cliffs. Kev looked at the slope with clear disappointment - it was far steeper than expected. As we pulled on our walking boots and gathered our optics, he announced that he wasn’t taking his scope, or indeed anything he didn’t absolutely need. I decided to carry mine anyway, reasoning that in the event we needed a scope, it would be worth the effort. Besides, how hard could it really be?
We started the ascent, surrounded by people apparently choosing to tackle the hill purely for enjoyment - completely mad, if you ask me. About three-quarters of the way up we stopped, partly to admire the view out across Eastbourne, but mostly to give ourselves a chance to get some air back into our lungs.
Not long afterwards we reached a fork in the path ahead, at which point Kev decided it was time to get his phone out and check the route. I got mine out an according to the map, we should have been taking the path nearest the coast, despite somehow finding ourselves inland of it. It quickly became obvious that we’d taken the wrong route from the very beginning and needn’t have subjected ourselves to that brutal climb at all - damn. We wouldn’t be returning back down though.
We continued until we came to Heathy Brow Car Park, which only added insult to injury. We could have parked there and avoided most of the ascent entirely - double damn. Kev took the discovery worse than I did. To be fair, I’d quite enjoyed the walk as I've been on a good number of walking holidays, though it certainly would have been better avoided if possible, especially as we were there for one reason only; to see the bird, and every wrong turn was eating into our time - it was suggested that it might show best between 9.00 and 11.00am.
From there the route dropped steeply towards the lower path and the pinned location where the bird had been showing. Looking down at the descent, it quickly became clear that while parking at the car park would certainly have made the outward journey easier, the climb back up afterwards would have been absolutely savage.
As we reached the pin location it became equally obvious that it wasn’t entirely accurate, and that we still had further to descend. That meant carefully picking our way down the narrow white chalk path along the cliffside - a section that felt far more precarious than anything we’d tackled so far. Later we heard that a few people had slipped on the chalk, though thankfully nobody appeared to have injured themselves badly.
The cliffs themselves were dazzlingly white in the sunshine, the exposed chalk glowing against the deep blue sea below. Formed during the late Cretaceous period some 70–100 million years ago, these cliffs began life beneath a warm tropical sea, where countless tiny marine organisms settled on the seabed over millions of years. Their compressed remains eventually formed the vast chalk layers now exposed along this stretch of coast.
Eventually we reached the spot itself and joined a dozen or so birders scanning the bushes, bramble, and scrub for the warbler. Looking back up towards the cliffs, we could see the smallest section of the climb we’d made, though without doubt it had also been the most treacherous.
The bird had apparently been showing quite well before we arrived, and we were quickly told where it had last been seen. We’d only been waiting a few minutes when it suddenly popped out of the scrub, flicked to the right, and vanished again before I could even get my camera onto it properly. It reappeared moments later, moved again, and then stopped just long enough for me to grab a few hurried photographs - enough at least to ensure I’d come away with something.
In the end, though, I needn’t have worried. Over the next hour and a half or so we enjoyed repeated views of the bird as it moved around the bushes and bramble, even if most of the later sightings were a little more distant than that first encounter. After all the climbing, wrong turns and scrambling down chalk paths, it felt like a well-earned reward for the effort it had taken to get there.
As time went on it appeared that the bird was becoming much more elusive and there were increasingly longer period between views. However, we were entertained by birds and seals on the coast and offshore, and even a spitfire overhead. The markings “ZP-W” on the photograph are not the aircraft’s original wartime identity, but a modern paint scheme applied to the restored flying Spitfire TE308, carrying the shark-mouth markings of No. 457 Squadron RAAF (Royal Australian Air Force), the “Grey Nurse Squadron”.
The actual wartime “ZP-W” was flown by Squadron Leader Bruce Watson of 457 Squadron RAAF. So, the aircraft in my photo is effectively a flying memorial scheme rather than an original surviving combat aircraft in untouched markings.
It was built at Castle Bromwich in 1945 as a low-back Mk IXe Spitfire and delivered too late to see combat in the Second World War. It then spent several years in storage after the war until it was later selected for conversion into a two-seat trainer version (T.9). Intended for export, possibly to Egypt, that sale never happened, and in 1951 it was transferred to the Irish Air Corps along with several other two-seat Spitfires. Today it flies on the UK airshow and experience-flight circuit.
Aircraft designers have long admired peregrine falcon because it combines speed, manoeuvrability and stability in ways that are remarkably efficient aerodynamically. While no aircraft is literally shaped exactly like a peregrine, many aspects of modern aircraft design echo features evolved naturally in fast-flying birds of prey.
The peregrine is especially influential because it is the fastest animal on Earth during its hunting stoop, reaching well over 200 mph (320 km/h). During these dives the bird changes its body shape to reduce drag. The comparison is especially apt when watching peregrines along sea cliffs such as Beachy Head. Seeing one sweep along the chalk face, banking sharply before dropping into a stoop, it is easy to understand why aerodynamic engineers and pilots alike find them so inspiring.
On a couple of occasions we saw a peregrine: first a brief view over the cliffs, then a single bird passing through, and finally two birds moving through over the beach behind us. Peregrine falcons are one of the signature birds of the cliffs around Beachy Head and the nearby Seven Sisters coastline with the sheer chalk faces being almost perfect peregrine habitat. I've read that a pair usually breeds somewhere along the cliffs most years, though exact nest locations are often kept deliberately vague to avoid disturbance. Spring and early summer is usually the best time to watch them, particularly for courtship and display flights, and then later when adults are hunting constantly for chicks.
Beachy Head has a long association with peregrines. Like much of southern England, the species disappeared from these cliffs during the pesticide era of the mid-20th century, suffering badly from chemicals such as DDT. Following the banning of those pesticides, peregrine numbers recovered strongly and they are now once again established along many of the southern coastal cliffs, including here at Beachy Head.
Birders continued to come and go throughout the late morning and early afternoon, though by now the views of the warbler were becoming increasingly infrequent and generally much more distant. We stayed for another half hour or so, chatting with some of the newer arrivals and reassuring them that the bird was still present and, with a bit of patience, would eventually show itself. Kev managed to pick it out for them on a couple of occasions as it flicked briefly through the scrub.
Eventually it was time for us to begin the journey back, though one thing had already been firmly decided - there was absolutely no chance we were returning the way we’d come. Instead, we dropped down onto the beach and followed it along beneath the cliffs until we reached a set of metal steps leading back up to the coastal path. From there the route was far more manageable. There were still a few sharp climbs and descents along the way, but nothing compared to the punishment of our outward route.
Along the return walk we added a pair of kestrels to the day list, along with several more stonechats, adding to those we’d encountered earlier in the day.
Back at the car we celebrated our success with some lunch from the kiosk before finally setting off for home, another lifer safely added to the list.
Year list: 251.
No comments:
Post a Comment