winds, broken cloud, mist patches and a little rain, perhaps contributing to the bird's landfall. Winds subsequently vee
Siberian Blue Robin at Minsmere: new to Britain Kieran Foster ABSTRACT A first-winter or female Siberian Blue Robin Luscinia cyane at Minsmere, Suffolk, on 23rd October 2000 became the first record of this species in Britain, and only the third in the Western Palearctic (following individuals on Sark, Channel Islands, in October 1975, and in Spain in October 2000). A subsequent bird on North Ronaldsay, Orkney, in October 2001 remains the only other Western Palearctic record. n 23rd October 2000, I decided to visit my sister in Leeds, but to do so via a roundabout route that would take in the Sociable Lapwing Vanellus gregarius and Pallas’s Leaf Warbler Phylloscopus proregulus that had appeared at Minsmere, Suffolk, during the preceding few days. Owing to the combination of a late start and heavy traffic, I did not arrive at Minsmere until late afternoon and I hurried towards the sluice bushes and adjacent levels hoping to find both birds before the daylight faded. On reaching the sluice bushes at approximately 16.50 hrs, I flushed a small brown passerine that showed a broad tail, creating the impression of a Locustella warbler. The bird dropped into the Marram Ammophila arenaria a short distance away, and I quickly relocated it, this time on the ground and noticed that it was unstreaked and had strikingly pale pink legs. Clearly this was not a Locustella warbler but a bird that I was unfamiliar with. It then flew again and I was unable to relocate it. Since there were several observers nearby, watching the Sociable Lapw ing, I asked another birder to help me to relocate the unidentified passerine. We returned to the area where I had last seen it but again failed to find it. Becoming increasingly frustrated, I returned to the sluice bushes, where several birders were looking for the elusive Pallas’s Leaf Warbler. Most seemed uninterested in my mystery bird, but after several minutes Mark Cornish and Mark Nesbitt agreed to help as
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they were returning to their cars at Sizewell. Almost immediately, Mark Cornish flushed a bird that he felt was a Dunnock Prunella modularis from the edge of the dunes, but I was fairly certain that this must be the bird. Shortly afterwards it flew again, and this time we saw it land. Luckily it remained in view, skulking at the base of a clump of Marram, and this time it gave better, more prolonged views. I was now able to note a pale buff eye-ring, stout bill, warm honey or creamy colour to the throat and breast, and smudged brown crescents on the breast. Faced with a bird that the four of us were still unable to identify, I ran to the edge of the dunes and whistled to attract the attention of the few remaining birders, including Paul Varney, who were still searching for the Pallas’s Leaf Warbler. Just as they arrived, the bird flew off, across the beach and out to sea. Thankfully, it returned quickly and dropped onto the shingle beach. One of those present then shouted ‘Swainson’s Thrush!’ [Catharus ustulatus], but although the colouring on the breast and the conspicuous eye-ring did give this initial impression, the bird was clearly too small to be a Swainson’s or any other Catharus thrush. The bird remained in view on the beach, apparently exhausted, for about 15 minutes, during which time it sat motionless, its head ‘hunched in’ and bill pointing skywards. Throughout, the sun was behind us, and the visibility and light were excellent. Even with these prolonged views, the observers remained 517
Siberian Blue Robin at Minsmere: new to Britain
perplexed and were unable to put a name to this bird, or even sensibly suggest which family it belonged to. I made a telephone call to Chris Batty and Andrew Raine at Rare Bird Alert, seeking their advice, while Paul Varney telephoned Richard Millington for his opinion. During these discussions, it was tentatively suggested that the bird may be a Siberian Blue Robin Luscinia cyane, and I was asked if the bird had a blue tail. Owing to the angle of the bird and the obviously short tail, I simply couldn’t be sure, so I moved along the dune to change my viewing angle. As I did so, the bird turned towards me, and it was at this point that it was seen to quiver its tail, and one observer thought that he saw a blue tinge to the tail. After approximately 15 minutes, the bird again flew towards the dunes and landed in a patch of Marram. It was subsequently seen again on three or four occasions, but only in flight, the final time being at about 17.50 hrs, when it flew over the dunes and was lost to view. In the failing light, it was decided that we should not disturb it again. We had seen it well on the beach and further flight views in poor light seemed unlikely to add substantially to our description. By this time, and following the telephone discussions, we became convinced that we could only have been watching a female or first-winter Siberian Blue Robin. News of the bird was released via the pager services and Birdline. Not surprisingly, the following morning saw a huge gathering of would-be observers, numbering in excess of 800 people, but despite extensive searching throughout the day, the bird was not seen again.
Description During the period that the bird was in view, the following description was taken.
Size, structure and behaviour In flight, it was clearly a small passerine, similar in overall size to Dunnock. During the initial views, it flew fast and low, and gave only fleeting glimpses, during which the tail appeared distinctly broad, creating the impression of a Locustella warbler. This impression was further reinforced by the distinctly two-toned appearance, the bird being dark above and pale below. Later, when it was watched at rest on the beach, where it gave prolonged and unrestricted views, the impression it gave was reminiscent of a small Swainson’s Thrush. This was, in part, 518
due to the combination of the coloration of the throat and upper breast, along with a conspicuous pale eye-ring. The bird was, however, distinctly smaller than Swainson’s Thrush, with a robust structure and short, broad tail that was seen to quiver. Throughout, the bird appeared exhausted, and sat motionless with its head hunched into the shoulders, and the bill pointing skywards, at about 45° to the horizontal. Later examination of video footage from China established that this behaviour is characteristic of Siberian Blue Robin.
Plumage Upperparts dark brown. One observer thought he noticed a blue tinge to the tail. Throat and upper breast warm honey- or yellow-brown in colour, and ‘necklace’ of smudged brown, downward-facing crescents on the breast. There was quite obvious demarcation between the warm-toned upper breast and the white lower breast and belly.
Bare parts Legs strikingly pale, ‘bubble-gum’ pink. Bill was large, strong-looking and dark, but with a pale grey base to the lower mandible. Eye large and dark, with warm buff eye-ring.
Associated species and weather conditions In September 2000, a high-pressure anomaly lay over Scandinavia, producing frequent southeasterly winds between Britain and the Baltic. During October, this anomaly intensified and extended eastwards. At the same time, the southeasterlies withdrew eastwards and became much more frequent than normal over the whole of Scandinavia, the Baltic and western Russia, while southern Britain was then dominated by winds from the southwest. As Siberian Blue Robin departs from its southern Siberian breeding grounds in September to winter in Southeast Asia, the track of the Minsmere bird prior to arrival on 23rd October is subject to considerable conjecture. The location and meteorological circumstances of its arrival seem to exclude the higher-latitude track more usually associated with vagrants from southern Siberia. This leads to the tentative conclusion that a leisurely westwards passage in fine weather through a ridge of high pressure over central Europe and Russia was the likely scenario. However, to survive such a leisurely passage, it would necessarily have had British Birds 99 • October 2006 • 517–520
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to remain within a suitable forested habitat zone. The distribution of this habitat type would suggest that its route in Asia was mainly north of latitude 55°N. If the bird was indeed newly arrived in Suffolk on 23rd October, it is possible that continued stimulation by fine warm conditions over Europe provoked a northwestward movement into Britain. A ridge of high pressure then extended from Ukraine to southern France, south to southeasterly winds extending over the whole of central Europe from 20th October. The warmest weather in The Netherlands and eastern France occurred on 22nd and 23rd, under clear skies. Further west, the southeast of Britain was subject to southwesterly winds from 17th to 19th, backing light southsoutheasterly from 20th. A weak, slow-moving front present early on 23rd gave light surface winds, broken cloud, mist patches and a little rain, perhaps contributing to the bird’s landfall. Winds subsequently veered southwest and strengthened as a more active cold front crossed the region later that morning. If the bird had arrived prior to 23rd, then it could have made landfall on or before 20th. Another Siberian Blue Robin was found at the Ebro River Delta, northeast Spain, on 18th October. While the route taken by that bird is equally uncertain, it seems more than a coincidence that two individuals were found in western Europe within five days. The comments above concerning the Minsmere bird could apply equally to the Spanish individual, apart from the final stages of its passage. During the first few days of October, exceptional numbers of Radde’s Warblers Ph. schwarzi appeared in eastern England, along with a sprinkling of the commoner Asian species we have come to expect at this time of year, including Dusky Ph. fuscatus and Yellowbrowed Warblers Ph. inornatus. This fall succeeded periods of southeasterly winds in late September. Most of October was, however, much less favourable to arrivals from the east, despite the continued southeasterly situation over Scandinavia. Westerlies predominated from 23rd October to the end of the month, and just a handful of Pallas’s Leaf Warblers appeared in Britain during the last ten days of October, including one at Minsmere. To the north, a Brown Shrike Lanius cristatus made it to Fair Isle, Shetland, on 21st October.
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Status and distribution Siberian Blue Robin is a summer visitor to a vast region of central and eastern Siberia, extending from the Ob River basin and the Altai Mountains of eastern Kazakhstan, east to Amurland and the Sea of Okhotsk, and from northeast China south to Hebei province, Sakhalin and northern Japan. Autumn migration begins early, with birds departing from the breeding areas in August and passing through the coastal regions of northeastern China in early to mid September. This species can be abundant at well-monitored migration watchpoints, including the coastal sites of Beidaihe and Happy Island, Hebei province, but to the south of the Yangtze River, it is uncommon throughout China’s coastal provinces. Carey et al. (2001) described it as a scarce migrant through Hong Kong, with numbers peaking there in late September. It would seem that most migrants pass inland across central China to reach Thailand and the Indochinese countries where many winter, while others continue south, to wintering grounds in peninsular Malaysia, Singapore and Indonesia. At Fraser’s Hill, Malaysia, where Siberian Blue Robin is a common autumn migrant, Medway & Wells (1976) noted the earliest occurrence on 16th September, with southbound passage continuing until 20th November. In Singapore, southbound passage into Sumatra peaks in the second half of October, with migrants recorded into early November, although many also remain here throughout the winter.
Other Western Palearctic records Prior to this bird, there had been just two records of Siberian Blue Robin within the Western Palearctic. The first, a first-winter female, was trapped on Sark, Channel Islands, on 27th October 1975 (Rountree 1977). This was followed, 25 years later, by a first-winter male trapped at the Canal Vell lagoon in the Ebro Delta, northeast Spain, on 18th October 2000 (Bigas & Gutiérrez 2000), just five days prior to the discovery of the Minsmere bird. Subsequently, a first-winter male was found on North Ronaldsay, Orkney, on 2nd October 2001 (Brown 2001). References Bigas, D., & Gutiérrez, R. 2000.The Siberian Blue Robin in Spain – the second Western Palearctic record. Birding World 13: 415–417. Brown, P. 2001.The Siberian Blue Robin on Orkney. Birding
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Siberian Blue Robin at Minsmere: new to Britain World 14: 422–423. Carey, G. J., Chalmers, M. L., Diskin, D. A., Kennerley, P. R., Leader, P. J., Leven, M. R., Lewthwaite, R.W., Melville, D. S., Turnbull, M., & Young, L. 2001. The Avifauna of Hong Kong. Hong Kong Bird Watching Society, Hong Kong.
Medway, Lord, & Wells, D. R. 1976. The Birds of the Malay Peninsula.Vol. 5: Conclusion and Survey of Every Species. Witherby, London. Rountree, F. R. G. 1977. Siberian Blue Robin: new to Europe. Brit. Birds 70: 361–365.
Keiran Foster, 125 Mill Lane, Sutton Leach, St Helens, Merseyside WA9 4HH EDITORIAL COMMENT Colin Bradshaw, Chairman of the British Birds Rarities Committee, said: ‘Since the majority of records of new birds for Britain are now submitted with a portfolio of documentation that includes video footage, pin-sharp photographs and numerous descriptions, we were, initially, a little concerned by the accounts we received. In fact, of the last 20 species new to Britain, only this bird and the Anglesey Grey Catbird Dumetella carolinensis have not come with a wealth of supporting evidence. However, an analysis of the various descriptions received showed a pleasing degree of consistency in key features from a group of people with no obvious previous connections. The lack of immediate recognition comes as no surprise, and the need for assistance (by telephone) to identify this species, which is usually known from images of spring males, is to be expected when confronted with an autumn immature on a cold October day. Although not well known, the features of birds in immature or female plumage, though subtle, are quite distinctive. The bright pink legs, large eye, scaled underparts and relatively short tail are characteristic of Siberian Blue Robin, and only Veery Catharus fuscescens and Rufous-tailed Robin Luscinia sibilans share similar features. These species show rusty tones on the upperparts, however, and so have an upperpart coloration which is quite different from the cold earth-brown shown by Siberian Blue Robin. In addition, the buffy eye-ring and throat, and gorget of crescents on the upper breast were spot on for Siberian Blue Robin as were the behaviour and posture. Like many skulking birds caught in the open, Siberian Blue Robin will often ‘freeze’ and show very well. The coincidence in timing with the individual in Spain and subsequent appearance of another the following year in Orkney added extra support to the record.’ Bob McGowan, Chairman of the British Ornithologists’ Union Records Committee, commented: ‘The Minsmere Siberian Blue Robin, seen by just a few lucky observers, was watched briefly on several occasions during a period of less than an hour towards dusk on 23rd October 2000. Unusually for contemporary claims for British firsts, it was not photographed. Owing to the small number of observers and the relatively brief views of the bird, this record struggled somewhat on BOURC circulation. Particular concerns were the lack of images, a significant identification hurdle for a potential first for Britain, and the number of Siberian Blue Robins in the bird trade. ‘Nonetheless, BOURC felt that the bird was sufficiently well described to confirm the identification as a first-year or adult female Siberian Blue Robin. Although this species is known to be kept in captivity relatively commonly, the circumstances of this record are indicative of the bird being a natural vagrant rather than an escape. The date and location were both consistent with natural occurrence, and coincided with the appearance of many other Siberian vagrants in Europe, including a remarkable 31 Radde’s Warblers (which share a similar range to Siberian Blue Robin) in Britain that autumn, a Brown Shrike in Germany as well as the one on Fair Isle, and two Siberian Accentors Prunella montanella in Finland. One significant factor that reassured the Committee that probability of natural vagrancy outweighed likelihood of escape was the discovery of a first-winter female Siberian Blue Robin on North Ronaldsay just one year later, on 2nd October 2001. Not only are the Northern Isles an acknowledged hotspot for eastern vagrants, but they are a considerable distance from the likely sources of escaped birds. ‘The positive identification at Minsmere and recognition of potential vagrancy allowed the acceptance of Siberian Blue Robin onto Category A.’
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