21 years ago, Hans ter Haar († 2011) invented a new way of rarity hunting in the Netherlands. After years of the classic Dutch Birding (whole) weeks on Texel in October, his eyes got stuck on Vlieland. Vlieland, next to Texel, was much narrower, almost wholly accessible and much smaller than Texel. So, it looks much better to cover with a fairly small group of birders. Also he thought that one full week was not the way; too much chance for a long slow period and too much chance of ‘the same birds’ every year. No, the plan was three long weekends spread out over the autumn between early Sept and late Oct. With not too much expectations but with humour and some self-mockery, Hans and his friends called their experiment ‘Deception Tours’. http://deceptiontours.nl/
Indeed some weekends were a deception (motivations were always high, but birds sometimes few), as on all island which lean on migration, but the concept was brilliant! The list of rarities found during the Deception Tours weekends is much too long to mention here, but to highlight a few: 5 new species/taxa for the Netherlands (Yellow-rumped Warbler, Turkestan Shrike, Pallid Swift, Northern Waterthrush and indeed Caspian Stonechat). The 2nd Bonelli’s Eagle for the Netherlands, and Vlieland, as small as it is, now host about half or more of all Dutch records of Olive-backed Pipit (7 in one weekend of which a group of 4!), Yellow-breasted Buntings, Rustic Buntings and Radde’s Warblers (4 on one day!). Hans sadly died just before the third weekend last year. Until his last days, although already very weak, he still supported us on Vlieland by phone. His motivation, insights, leadership and great company we will continue to miss.
In the overcrowded Netherlands, Vlieland is the most ‘remote’ inhabited island. It has a population of 1100 people and the ferry arrives just three times a day. UK birders will be laughing now, and yes we can only dream about isles like Fair Isle, Foula, St Kilda etc. Cars are not allowed for visitors on Vlieland, so birding goes by bike and by foot.
The weather maps are my compass. After quite a long period of bad situations, finally a narrow ridge of high pressure waved over Southern Scandinavia during the second Deception Tours weekend (5th -7th Oct). On Saturday early morning the back of a frontal zone passed Vlieland and already huge numbers of thrushes, mostly Redwings were coming in while still raining. The excitement in the air sunk quickly down into our veins, our team prepared for code red…
For me and my friends, the fall phenomena is a wonderful event in itself, whatever including rarities or not. But the excitement went to a climax when Eddy Nieuwstraten and Han Zevenhuizen bumped into a Siberian type Stonechat with white in the tail… A ring from Han and within minutes I was with them: WOOOOW a cracking male variegatus!! Beside the ‘black-eared wheatear-tail-pattern’ the bird shows • a huge whitish (not uniform buffish) uppertail-coverts and rump-area, • very broad orange neck-side patch, strongly narrowing the black mask towards the rear-side • sandy-grey fringes to the mantle-feathers and scapulars, and • an almost maximum contrast between black underwing-coverts and white bases of the underside of the flight-feathers (latter from photo’s). All spot-on for variegatus.
The bird was a splendid male with such a deep black face, seemingly full set of adult-type wing-coverts, narrowly pale edged primary-coverts and blackish primaries that, at first I thought it have to be an adult male. I knew that at least some first winter males variegatus are much more ‘adult-like’ than maurus first winter males, but this seems too much.
In the 2nd part, below, the ageing of this beauty is further clarified. The earlier presumed age as a first winter by the presumed diagnostic tail-feather shape appeared to be incorrect.
The taxonomic situation of variegatus is still unclear, but for the time being widely regarded as a form of Siberian Stonechat and forms a group with armenicus: the Caspian Stonechat. Whatever future DNA studies will discover, for birders, the males are very distinctive by at least their tail-pattern. I think the most interesting thing is that first winter males variegatus in autumn are often already much more ‘male-like’ compared to first winter male maurus (which are often hard to tell from females). To highlight some possible reasons for this: • a difference in body moult-strategy between the two taxa (with maurus acquire a black mask by moult not before the winter)? • larger pale tips to the body-feathers of maurus, concealing the male-like plumage tracks? and/or • earlier breeding season of variegatus (due to the more southern breeding range) resulting in older first winter birds which are more advanced and thus more ‘adult-like’? As far as I know, this is not clear, and some first winter male variegatus are much less advanced and thus more similar in body-plumage to maurus. Maybe there are readers who know more? The Vlieland-bird had already moulted most or all wing-coverts, some secondaries and possible the upper two tertials. Also several secondaries went missing during its two week stay, maybe due to active moult. The more adult male-like plumage compared to most vagrant (first winter) maurus in Western Europe in itself seemed to be an interesting starting point for future discoveries, before the tail-pattern is seen. Females are, as far as I know, identical to maurus (females). Maybe some show little pale at the base of the outer-tail feathers, normally invisible in the field.
Part 2: Caspian Stonechat on Vlieland, the ageing reviewed
Thanks to Magnus Hellström, Tom van de Have and Brian Small, now we can firmly say that it is indeed an adult (2cy+).