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| Gib Point 16th March 2008 http://lbcarchive.co.uk/forum/viewtopic.php?f=2&t=7349 |
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| Author: | Andrew Chick [ Sun Mar 16, 2008 8:45 pm ] |
| Post subject: | Gib Point 16th March 2008 |
A rubicola type male Continental Stonechat with a party 5 hibernans just south of Mill Hill, Gib Pt, this evening (16th March). Also a single Firecrest in the east dunes. Report sent in by James Siddle |
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| Author: | Edmund Mackrill [ Mon Mar 17, 2008 9:04 am ] |
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Very interesting James. As someone who looks carefully at Stonechats I would like to know what criteria you are using to differentiate in the field between hibernans and rubicola. Lars Svensson - ID guide to European Passerines - essentially for ringers - says " hibernans is very similar to rubicola but somewhat darker in fresh plumage". Did your rubicola appear so much paler than the hibernans? Indeed could you have picked it out were it on its own? Not questioning the record but I'm sure there are other Lincs birdwatchers who would like to know how to ID them. Thanks for any reply. Edmund |
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| Author: | Stephen Routledge [ Mon Mar 17, 2008 9:32 am ] |
| Post subject: | Gib Point |
In reply to the above Ed,there is a photo of a claimed 'Rubicola' on the recent sightings page of Portland observatory,the bird in question does have a darker head and overall paler body,almost looking like a male 'Sibe' Stonechat,hope this is of interest. Regards Steve. |
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| Author: | Edmund Mackrill [ Mon Mar 17, 2008 6:44 pm ] |
| Post subject: | |
Thanks for that Steve. Let's see how many rubicolas we can find in Lincs over the next month or so!! |
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| Author: | Andrew Chick [ Tue Mar 18, 2008 1:57 pm ] |
| Post subject: | |
Hi Ed, First of all I identified the bird as a rubicola-type. The problem being, in my opinon, the limits of current knowledge of the forms hibernans and rubicola. In terms of the identification, I used the following composite of characters; extensive white on the rump with only a few of the lateral rump feathers showing dark (brownish-black) shaft streaks; a bold blaze of white across the sides of the neck; the red/orange colouration on the underparts was more restricted than would be expected for hibernans, and the lower belly was whitish and this extended up towards the centre of the breast. In adddition, the rather extensive amount of white on the wing and the colouration of the red/orange on the underparts gave further support. Unsurprisingly, I wasn’t able to make any accurate judgement on the quality of black on the underwing. The problem here, as already mentioned, is the current known variation of the two forms. This bird was not as obvious a rubicola as many breeding in southern Europe, but may be typical for more northern populations. In the UK, where only hibernans has been thought to breed, I have seen birds similar to the Gib male breeding in both Kent and Scilly. Additionally, birds ascribed to hibernans breeding in Portugal are, to my eyes, clearly rubicola based on current descriptions (e.g. Cramp 1998 and Urquhart 2002). Basically, the bird at Gib falls into the group being currently described in the recent literature as Continental Stonechat. However, current knowledge of the extent of the variation in both forms makes it hard to be certain. It would seem there is a gap out there to document the occurrences of these birds nationally and it would be very interesting to see if any other observers are reporting rubicola-type birds in Lincs. Kev Wilson once told me that he hadn’t seen any at Gib, so maybe they are uncommon in the county. James |
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| Author: | Edmund Mackrill [ Tue Mar 18, 2008 8:46 pm ] |
| Post subject: | |
Thanks for the reply James. I've had the day at Gib and looked at 3 male Stonechats all of which appeared less richly coloured on the underparts than the birds that have been wintering. I didn't manage a view of any rumps. There are 407 photos of 'European' Stonechat in the Bird Guides photo album, quite a few of which seem to fit your description of rubicola but no rumps visible of course. So more effort to see rumps next time but Svensson does comment that white rumps are associated with worn plumage which should not be the case at the moment. However, you have certainly got me interested and I shall be paying much more attention to coastal Stonechats from now onwards. Does anybody else have any comments?? |
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| Author: | Kev Wilson [ Tue Mar 18, 2008 10:15 pm ] |
| Post subject: | stonechats |
Ed/James I have not positively identified rubicola at Gib but may well have overlooked them - I think I will be giving stonechats the attention they deserve in future though ! I saw the group of five birds that James saw and noted the plumage detail of the male which certainly did have a pale rump - also I got the impression that none of the females looked as dark and dingy as standard hibernans - (this is probably irrelevant !?)will be consulting BWP very soon!! Cheers Kev |
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| Author: | Graham Catley [ Tue Mar 18, 2008 11:40 pm ] |
| Post subject: | |
I thought the latest thinking was that rubicola and hibernans are one and the same and indistinguishable but cannot remember which paper I read it in; my thoughts are that the later birds now going through are likely to be first-summers, not in such a rush to occupy territories and that may be why the females look more washed out on the underparts and the males less richly coloured than adult males which may have wintered; logic suggest that birds moving through at the moment are likely to be going north not south so they are more likely to be British bred birds heading for home after a winter in N France or the Med rather than continental birds coming this way |
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| Author: | Edmund Mackrill [ Wed Mar 19, 2008 9:06 am ] |
| Post subject: | |
Great response. I've had a search of google and here are a couple of comments from Bird Forum which seem to sum things up: 1- "Looking at the breeding distribution again, I'd suspect most if not all of the Belgian breeding Stonechats are hibernans, as they are clearly part of a linked population, with a wide gap in the breeding range across Germany to where rubicola breeds in Poland southward. Presumably intergrades in south & central France. There isn't much agreement in the literature as to where the divide between the two races is, some say hibernans in Ireland only, others say Ireland, Britain, western France, western Spain. Some even say that the range of individual variation within populations is so large that maintaining hibernans as a distinct race at all is barely justified." 2- "The differences between most hibernans and most rubicola are so subtle that individuals cannot be identified to race even in the hand. Certain described plumage traits represent small average differences only and some birds from either end of the spectrum of variation probably match certain individuls from the opposite end. On this basis I'd wholeheartedly agree that hibernans is an invalid race. Although some birds might appear that seem distinct enough to be rubicola, this can never be proven, most are inseperble and nothing is really gained by recording either. Those striking apparent male rubicola that do occasionally turn up are liable to be confused with Siberian maura. All of the subtle and inconsitent plumage traits which might be used to suspect a rubicola over a hibernans in the UK are small steps towards the appearance of maura but almost all can be occasionally found in breeding hibernans in Britain too." Also from "checklist of bird taxa occurring in Western Palearctic region with distributional notes on subspecies - 15th Draft" Common Stonechat Saxicola torquatus Rubicola-group (1) hibernans Northern Portugal, north-west Spain, western France, Britain, Ireland, and along coast of southern North Sea north to at least western Netherlands [include th eresae ] (2) rubicola North-west Africa and southern and central Europe (except for area inhabited by hibernans), east to western and northern Turkey, western Transcaucasia, western Caucasus, and Ukraine [includes graecorum, gabrielae, amaliae] So rubicola is unlikely to occur on distributional grounds - in spring at least - and perhaps not distinguishable from hibernans at all. Autumn with Stonechats is, of course, a different story. |
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| Author: | Andrew Chick [ Thu Mar 20, 2008 9:12 am ] |
| Post subject: | |
Posted for James Siddle who is in the process of joining the LBC It’s certainly been very interesting reading all the responses. Having lived in Portugal for several years where I rarely met another birder, it has been most enjoyable for me to read such erudite and interesting responses to the original post. I agree with GPC about the likelihood of late migrating Stonechats being first summers. I did try to age the Gib bird, as there seemed no obvious contrast between the remiges and the wing coverts and I suspected this bird to be an adult. However, with difficult viewing conditions (high winds, poor light and sea mist!) I am far from certain about this. As GPC says it has been mooted that the Stonechat population is merely clinal of a single race. The Dutch CSNA, for example, have treated hibernans as a synonym of s. rubicola. Additionally, Urquhart(2002) also emphasises the great difficulty in separating the subspecies, especially where the populations meet. In terms of range, according to Urquhart hibernans breeds in ‘western and possibly southern Norway, the UK, south to France (western Brittany) and the west coast of Portugal’. With rubicola the ‘northern boundary of this subspecies borders the North Sea stretching along the coasts of France (excluding western Brittany) Belgium, Netherlands and Germany to Southern Denmark.’ Eastwards I have noted rubicola breeding in Armenia, whilst recent research suggests that in may also occur in Iran (Kirwin and Bates in prep). ‘The western limits of its range extend southwards down the Atlantic coast of Europe to the Iberian peninsula (apart from western Brittany and Portugal)….it inhabits North Africa from Morocco through northern Algeria and northern Tunisia’. From ringing recoveries the vast majority of UK ringed birds recovered on the continent have been from Spain, although one reached as far south as Morocco. There is also an example of a Spanish ringed bird recovered in the UK, which may, on date, have been a rubicola rather than a returning British bird. With regard to the morphology of the Stonechat population at the extremes of the range i.e. from Norway and Scotland and the Mediterranean basin there is, in my opinion, a distinct plumage variation. The problems occur in the intergrade zone between the populations, of which we may lie towards any hypothetical boundary areas (perhaps the fulvescens population of the, admittedly much more widely distributed, Chiffchaff would be analogous). In Portugal (where as I have previously stated the whole population resembles rubicola rather than hibernans) the males there often recall Siberian Stonechat having large, often almost unmarked white rumps, often pale fringes to the lower back feathers even in early spring, a broad blaze of white across the necks extending round the nape, extensive white in the in the wing, limited orange colouration in the underparts and very dark underwing coverts. These birds are very distinct from those in the northern Britain. Assuming both subspecies are valid, whether the pale birds we are seeing in the UK are rubicola or hibernans is, obviously, extremely difficult to say. However, birds exhibiting a combination of characteristics typically associated with rubicola appear to occur as both migrants and in the breeding population. This breeding population may be confined to southern England (?). For example, when I lived on Scilly of the breeding Stonechat population I checked there (approx. 60 pairs) less than 5% showed characteristics of rubicola. With the populations north of Lincs grading towards the dark extreme of hibernans, rather than these pale birds, would it seem unlikely that the Gib bird was thus a bird heading north as GPC suggests? In addition, as already mentioned by Stephen, a small number of these interesting looking birds are now being regularly reported at well watched sites on the south coast, for example Dave Walker at Dungeness reports ‘rubicola-type’ birds on the 12th and 14th March. Personally, I feel the case is very much open on these birds. I wonder, for example, if any of the ‘100 plus or possibly double that’ which passed through GPC’s local area in 10 days showed similar features? |
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| Author: | Alex Lees [ Thu Mar 20, 2008 11:37 am ] |
| Post subject: | |
Regardless of whether rubicola is a synonym of hibernans (I haven't looked at skins so won't comment), it is entirely concievable that rubicola phenotype birds could occur as overshoots with movements of British hibernans at this time of year, as Iberia and the western Med are important wintering areas for the latter. There are recoveries for example of British bred hibernans in Algeria (Brown & Grice 2005). There has been an impressive push of Stonechats through eastern England in recent days including an estimated fall of 40 on Blakeney Point: http://www.uea.ac.uk/~e039/ilyabirding.htm Good to see such a scholarly discussion going on here..... |
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| Author: | Graham Catley [ Thu Mar 20, 2008 2:54 pm ] |
| Post subject: | |
Quote: I wonder, for example, if any of the ‘100 plus or possibly double that’ which passed through GPC’s local area in 10 days showed similar features?
Yes! I had one reported with a bold white rump and restricted orange underparts and broad white collar but I must admit that I have not come across any this spring although I have seen them in the past up here in early March and some people may remember that the male of the pair which bred at Saltfleet in 1980 was thought to be rubicola as it had rather distinctive plumage traits which after 28 years I cannot recall off the top of my head although I do remember a white rump a broad white collar! |
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| Author: | Edmund Mackrill [ Thu Mar 20, 2008 8:21 pm ] |
| Post subject: | |
It's a pretty nasty forecast for the long weekend and if unable to get out looking at Stonechats I suggest a cosy hour or so in front of the computer monitor going through the hundreds of European Stonechat photos in the Birdguides album. Most plumage types are represented and it will sharpen you up for when next out in the field!! http://www.birdguides.com/pictures/default.asp |
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