A brief spell of easterly winds this week brought a star-studded influx of migrants from the east. The standout was a stunning Siberian Robin, found by well-known local birder Hugh Harrop in his Shetland garden—an extraordinary addition to his garden list!
In previous years, I would probably have been on Shetland at this time of year. However, Costa Rica showed me the delights of overseas birding, so instead I am going to The Gambia with Naturetrek in March. This will be my second visit to this African birding mecca; the first was with my then-girlfriend, just after I completed my PhD—a rather sobering 45 years ago!
Among these eastern rarities, my choice was between a Sykes’s Warbler in Aberdeen and a probable Eastern Bonelli’s Warbler at Gibraltar Point. Both were found on Wednesday afternoon and remained until nightfall. The Sykes’s would have meant an 800-mile round trip and an overnight stay, so I foolishly opted for the Bonelli’s. Why foolishly? As readers of my previous blogs will know, this little blighter has quickly become my latest bogey bird: two long-distance dips last month, plus another in Kent last year when I missed it by just ten minutes.
A brief explanation of Bonelli’s Warblers: two species are recognised, Western and Eastern. I have dipped the Western several times but have never previously gone for the much rarer Eastern, of which only eight records had been accepted by the end of 2024. The word ‘probable’ appears in the blog title because the two species are extremely difficult to distinguish visually. That raises a reasonable question: why treat them as separate species, and might they eventually be lumped together? Supporting their current classification, their ranges do not overlap and their mitochondrial DNA sequences differ markedly. In the field, however, they can be reliably separated only by their distinct calls. When the Gibraltar Point bird was first found, two reliable birders heard it call and identified it as Eastern.
Given my history with Bonelli’s and the drive of more than three hours, I waited for a sighting report on Thursday morning before setting off just before 8 am. Unfortunately, that cautious decision put me in the middle of the morning rush hour, and it was nearly midday when I finally arrived. The warbler had last been seen for ten seconds at 10:40 before vanishing into the scrub. The warblers location, Sykes Farm, was surrounded by dense scrub and small trees—plenty of cover for an elusive warbler. I joined about 20 other birders watching its last known position in a tree, and after an hour I began to feel a dispiriting sense of déjà vu. Then everyone suddenly hurried to the other side of the farm, where the elusive warbler had just been spotted!
After a few minutes, it miraculously flew from a bush and briefly landed on dead branches directly in front of us. There was no time for photos, but at least the Bonelli’s curse was broken, giving me my 438th UK tick!
Here is what can only be described as a statistical anomaly: I seem to have far more success twitching very rare warblers than comparatively rare ones. This Bonelli’s is a case in point—I ticked the much rarer Eastern but dipped the Western. The same pattern holds for the Subalpine Warbler complex. Of the three recognised species, I have seen the rare Eastern and the very rare Moltoni’s (just 16 UK records), yet repeatedly dipped the Western, despite a handful being recorded most years. An odd one!
The Eastern Bonelli’s Warbler, Phylloscopus orientalis, breeds in south-eastern Europe and Asia before migrating to sub-Saharan Africa for the winter. Adults have plain grey-green upperparts, a green-tinged rump and wings, whitish underparts, a small pointed bill, and brown legs. As with most warblers, the sexes look alike. Its call is a hard chup, clearly distinct from the Western Bonelli’s Warbler’s disyllabic hu-it.
Over the next few hours, it reappeared several times in a bush directly in front of us, flitting restlessly among the leaves like a typical Phylloscopus warbler and occasionally emerging into the open. The same bush attracted one or perhaps two Yellow-browed Warblers and several Chiffchaffs, all picking insects from the twigs. During this time, I managed to take a few half-decent photos of the Bonelli’s. It’s much paler plumage, particularly on the breast, made it fairly easy to distinguish from the bush’s other occupants.
At 4 pm, I decided to leave. It is difficult to describe how the elation of a successful twitch compares with the pain of a dip. It is a win-or-lose game, with no real possibility of a draw. I need to remember this high when the next big dip inevitably comes!
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