aPalling Birding
The escapades of a Norfolk country gent and birder
Greenish Warbler influx 2007
Background
The Greenish Warbler Phylloscopus trochiloides viridanus is the western subspecies of Greenish Warbler P. t. trochiloides. The taxonomy of the Greenish complex is, er, complex. But basically 'our' viridanus spreads east to western Asia where it meets the eastern race plumbeitarsus which you may know as Two-barred Greenish Warbler (or that gap on your tick list between Greenish and Arctic). Although these two overlap they behave as good species and show no signs of intergradation. Hence, good species right? Hang on. Viridanus also extends south towards Afghanistan, all the way round to north-east China where it almost meets plumbeitarsus again (and would actually meet it if there were any habitat left). As viridanus goes round this southern route it goes through three other subspecies smoothly intergrading – into ludlowi in the west, trochiloides through the Himalayas and obscuratus into north-east China.
Mmm.. doesn't that leave a big hole in the middle of Asia with no Greenish Warblers? Well spotted, it certainly does and this is because the centre of Asia is a pretty inhospitable place for Greenish Warblers as it includes the Taklamakan Desert, the Tibetan Plateau and the Gobi Desert. So what we have is a 'ring' where the opposite ends in the north of the ring are good species but to the south it's one smooth intergradation. See the map below if you have a headache. The blue one is our viridanus, the red is plumbeitarsus, and the others are, well, lets face it, you've lost interest now. Having been lucky enough to see five of these six races I can atest that the obscuratus race's song is different to viridanus, being longer and more complex. By the time this has become plumbeitarsus and headed west across Siberia, you can't get a desparate viridanus to even cast a sly glance at it. So, is this a true ring species or the result of post-glacial expansion of two populations (eastern and western, split by the ice) which met again as the ice retreated, with the birds south of the Tibetan Plateau recognising each other but birds north of it not? Dunno, but it's the sort of thing that excites a lot of people and I'm sure they're on their way to solving the problem.
Look into the ring, look into the ring, don't look around the ring, look directly into the ring, you're under!
Asia! Don't you love it!
The Norfolk 2007 influx
Anyway, enough of that blather. What about Norfolk?
Greenish Warbler has been a rare autumn vagrant in Norfolk ever since the first bird was recorded on Blakeney Point on September 6, 1951. Typical place, typical-ish date. There were no more until 1967, remarkably enough, but since that time the bird has occurred in very small numbers anually, with the occasional blank year such as 2001, with small peaks in influx years such as five in 1972, seven in 1987, nine in 1985 and now an astounding 30-35 individuals in August 2007. Birds generally occur in mid-late August on easterly or south easterly winds accompanied by low cloud or rain which grounds them. This was by the far the biggest influx and fits the pattern in terms of timing and conditions. The graph below shows the distribution of occurences by date. Numbers are on the conservative side. Yes, I know the y-axis label is missing...
The first birds were recorded on the 21st as an occluded front moved over eastern England with associated north-easterly winds.
Aug 21st
The occlusion is the curled line with triangle (cold front symbol) and semi-circle (warm front symbol) over East Anglia. The isobars show the wind direction (NE or ENE). The cold front has caught up with the warm front, undercut it and joined the cold air that was ahead of the warm front.
Up to four (or five) were found on Blakeny Point on the 21st, staying overnight in rough conditions as the front occlusion moved through eastern Norfolk bringing heavy rain and winds. Further birds were found on 22nd and 23rd as the occlusion hung over Norfolk and a remarkable total of around 16 birds was present on the 24th including six on the point.
On the 24th, the occlusion was still over eastern England and there had been no real change in the weather since the 21st.
By the 25th the weather was sunny and warm and that night most birds moved out on the clear skies. I expect most birds arrived fairly early on in the bad weather and were picked up as it became aware there was a major influx happening. A great start to the autumn and it provided me with my first decent Sea Palling / Eccles rare and pleased the local birders as it was the one phyllosc, aside from Radde's, that hadn't occurred there since the area began to be covered in about 1996. The Radde's I found a few weeks later was the icing on the cake! A few of the birds were noted as singing a sub-song and the Eccles bird was heard to call a few times and Dave Farrow also heard it 'singing' I think.
The 25th August showing warm, calm conditions, conducive to an exodus of Greenish Warblers.
Identification
This excellent and instructive photo of a Greenish Warbler was taken by Paul Baxter in 2006.
Please visit the Fair Isle Bird Obs website:
http://www.fairislebirdobs.co.uk/
One of the easier phylloscs to identify. If you've had previous experience of them abroad then you'll find it straightforward after the initial surprise. Basically they're superficially like a mix of Willow Warbler, Wood Warbler and a Chiffchaff. They have the cleanish appearance and strongish face pattern of a Willow, the brightness of a Wood and the short wings of a Chiff. The supercilia should be striking, long, pale and meet over the bill. The underparts should be decidedly pale or whitish, with a pale yellow wash apparent on the breast only at very close range, if at all. The remiges should be edged green and there should be a greater covert bar that may or may not be sullied yellow. The bill should be yellow/orange on lower mandible with a dark upper mandible / culmen. Legs are on the dark side but prone to appear a multitude of colours being brown on front and a pinky-grey at the rear so best not put to much store by them. They are restless birds and flick their wings habitually.
Arctic Warbler is the real confusion species but date should be a good first indicator with Arctic being a much later migrant. Arctics have a super that doesn't bridge, blotchy cheeks and strongish, yellow straw legs. Their bills are spikier and their wings show a longer primary projection.
Calls are an excellent pointer with Greenish having a disyllabic chee-wee or tee-wee or similar - a bit like a Pied Wag - while Arctic has an 'explosive' Dzik! that once heard, is never forgotten.
Greenish calls:
http://www.dutchbirding.nl/sounds/gwarblercall.ra
http://www.dutchbirding.nl/sounds/gwarblercall2.ra
http://www.ncbs.res.in/citsci/migrantwatch/Phyll-trochiloides-PratapSingh1.mp3
Greenish song:
http://www.dutchbirding.nl/sounds/gwarblersong.ra
http://www.dutchbirding.nl/sounds/gwarbler.rm
Arctic call:
http://nikonf.hp.infoseek.co.jp/arcticr.mp3
References
Collinson, M. 2001. Taxonomic research update Greenish Warbler, 'Two-barred Greenish Warbler', and the speciation process. British Birds 94: 278-284.
Elkins, N. 2004. Weather and Bird Behaviour. Poyser, London
Taylor, M., Allard, P., Seago, M., and Taylor, M. 1999. The Birds of Norfolk. Pica Press, Sussex, U.K.
For more on migration and vagrancy see:
Gilroy, J.G. & Lees, A.C. 2003. Vagrancy theories: are autumn vagrants really reverse migrants? British Birds, 96: 427 – 438 http://www.freewebs.com/alexlees/Gilroy%20&%20Lees%202003%20Vagrancy%20theories.pdf
Here's something basic on Dark-breasted Barn Owl in light of the recent run of records. If you have anything to add, or any relevant comments, then just email me.
Background
Tyto alba guttata – the 'dark-breasted form' of Barn Owl, oddly enough known as Dark-breasted Barn Owl (does what it says on the tin) has been recorded in Norfolk as a scarce vagrant for a number of years now. Other east coast counties have had similar records, with some of the birds involved having borne rings, confirming a continental origin in at least some of those individuals recorded. It is a native of southern Sweden, Denmark, the Netherlands and Germany east to w. Russia. Southwards it reaches the Alps, Austria, Hungary, Bulgaria and The Crimea. Where the range overlaps with that of alba, interbreeding occurs.
Norfolk Records
records for Norfolk since 1970 are as follows - singles unless otherwise stated:
1975, 1976, 1978, 1979, 1985, 1990 (2), 1991, 1994, 1995 (four), 1997.
Fuller details of birds since then:
Kelling 29th - 30th Oct 1999
Waxham/Sea Palling Mar 4th - Apr 5th 2003
Welney Jan 15th - Mar 23rd 2003 (see photo link below)
East Ruston 19th -26th Jan 2004 (see photo link below)
Weybourne Oct 18th - 19th 2004
Ludham Dec 21st - Jan 5th (photo) 2007/2008 http://www.gybc.org.uk/year/photos2008.htm
And Long Stratton currently http://www.birdforum.net/attachment.php?attachmentid=124743&d=1202334326
Other Images
more images of some recent birds are here http://www.surfbirds.com/cgi-bin/gallery/search2.cgi?species=dark-breasted+Barn+Owl
compare to typical Barn Owls here: http://www.surfbirds.com/cgi-bin/gallery/search2.cgi?species=Barn+Owl
http://www.birdfoto.fsnet.co.uk/birds2002/barnowl.html
Identification
Identification of a guttata is not simple and as far as I know there is no diagnostic difference; a lot is presumed, due to location and date. An east coast record in winter / early spring is looked upon more favourably etc.
Firstly, lets look at variation in alba Barn Owl: males are paler, females are darker. That's it in a nutshell - it's obviously more complicated than that but not a lot. At the extremes, males can be very pale indeed – we've all seen birds that appear almost ghostly white above and below - while darker female birds can show a lot of grey on the upperparts and a buffy suffusion to the upper breast. The problem therefore is how to tell if your bird blogging around a Norfolk rough pasture in Jan. is a guttata or a dark female alba...
Generally, a guttata is a 'darker' bird with some amount of dark buff on the breast (but not essential, which gave me a surprise), possibly the belly and flanks too. This belly flank area usually has some dark spotting, larger than in alba. There is usually some similarly buff-coloured feathering on the underwing coverts including the underwing primary coverts. Alba only show a little buff suffusion, if any, here. The upperparts are darker grey http://www.hughharrop.com/rarity_pic.php?pic_id=2156&cat_id=2004, sometimes to the extent that it is hard to see any buff, with the wings appearing more barred and the tail too appearing darker and heavily barred http://www.hughharrop.com/rarity_pic.php?pic_id=2155&cat_id=2004. The eye surrounds have more dark feathering than in alba.
Note the buffy suffusion on the underwing coverts in the pic opposite of the Ludham Dark-breastd Barn Owl, and the buffish tone to the flanks and belly below the 'half-breast' Click on the image for a large version. Huge thanks to Andrew Grieve for the fantastic images - please see http://www.gybc.org.uk/index.html
In this pic of the Ludham Dark-breasted Barn Owl, you can clearly see a dull buffish suffusion to the lower breast and belly below the prominent half bresat band. The upperpaprts of this bird were also noted as being very grey but this was not captured in any images.
Click for a large image. Again a big thank you to Andrew Grieve and GYBC for permission to use these pics. Please visit the website http://www.gybc.org.uk/index.html
AG (pers. comm.) has seen similar half-breasted birds coming in-off the sea in Sinai (Egypt) - presumably birds with a SE Russian origin.
So, if your bird has very grey upperparts, some buffish suffusion on the breast with some spotting on the belly and/or flank, a reasonable amount of buff on the underwing, darker eye surrounds than you might reasonably expect and it's on the east coast in winter or early spring, you might have a shout at guttata. But...
Can alba pairs throw up offspring marked like a guttata? Well, in BB (99) pp210-211, Paul French documents a pair of Barn Owl offspring discovered in 2002: one normal alba, one with the characters of guttata. Unfortunately the parent of these birds were not seen, so one may have been a guttata. In 2003, a pair of alba were found to have produced two guttata-type chicks. These characters could, of course, have come from some contact with guttata genes in the recent past, either from a wild bird or from a released bird of 'dodgy' parentage. Alternatively, they could just be part of the 'normal' variation in alba. In which case we're all buggered.
Summary
So, I reckon if your coastal at the right time of year, and your candidate shows the features described above, you're in with a shout but if it's inland, you only notice a couple of features or you didn't pick up from the roadside with some bling on it, it might be trickier to make a case... decent field notes or a photograph showing the salient points will ease your conscience. It seems an upsurge in records might be on the cards with three (not yet fully documented) birds reported recently, apart from the well-documented and photographed bird at St Benets. Hopefully this page will help people to know what to look for when they encounter and interesting Barn Owl. If you get a chance to see one, go for it. The Ludham bird was criminally neglected. They aren't a tick but they're super smart and seeing one flapping lazily over the rough grasslands of east Norfolk is quite a treat.
So, have you seen one? You decide!
Special thanks to Andrew Grieve for instructive and helpful comments and photos and GYBC for allowing their use
Birding or Pagering?
Well, they say taste is the enemy of art so here're some tasteless ramblings that might seem dazzlingly artful of clever to any idiots out there reading them. Or not. Innit.
Ok, so you've spent £3000 on your top-of-the-range bins and scope, another wedge on a DSLR, you've got a big tripod and a pager, and no doubt you're a 'serious' birder... so why drive 200 miles to stand ten yards away from a Lapland Bunting that's been there weeks, feeding on seed put there to attract them? Hardly requires any skill does it? And it's not much of an 'outdoor experience'! Although the cafe latte that you can now enjoy with your Laps in the Salthouse car park is quite nice I'm told.
Well, the short answer is that you wouldn't know a Lap from a Linnet if it flew over your head calling on a windy October day on the coast, and you'd never find one on your own. And the thought of walking around Blakeney Point or Waxham all afternoon and seeing nothing while your friends are the 500th and 501st people to see the Great Grey Shrike and Black Brant probably fills you with dread. You're not birding, you're 'pagering' Is there a difference? Good question, thanks for asking. Read on - if your post-modern attention span allows...
Mmmm, well by now you're probably spitting feathers at my presumption and prejudice and yes, there's obviously more to the issue than meets the eye. I'm not talking about hard-working patchers who have the occasional weekend away or folks after a mega like the White-crowned Sparrow. I mean those whose birding is dictated by their pager. Hareing around after birds may satisfy some deeply-seated desire that men have in them, related to the hunter-gather instinct or it may just be the anally-retentive outcome of a less than stimulating childhood combined with the need to get away from the other half and the unrelenting boredom of the 9-5 and murderous blandness of Big celebrity cooks dancing on ice in the jungle' presented by some squealing shitcake with half the sincerity and twice the charm of Dr Goebbels and the like, that comes through our cathode ray tubes day in day out. You decide.
The strange thing is, it seems to me that more and more people are starting to twitch relatively common birds – it's something I've heard others say too – and I'm sure it's happening. Yes, we can all enjoy birds in our own way and going from one scarce bird to another is entirely harmless I hear you say and I pretty much agree but there comes a point when if you think you're a birder, then you really ought to start doing some birding. I used to be partly guilty of a similar thing when I used to twitch a lot but at least after seeing the main attraction (I'm talking a proper rare here not a Rough-legged Buzzard), I'd spend a day or two in the area looking for other bits and pieces. Nowadays it seems to be a procession from one bird to the next (many certainly not rare, some hardly scarce), a process which will not lead to any improvement in your ability to actually identify anything, or more importantly, to find anything new of your own. But hey, you enjoy it so what's the harm? Well, none to be honest but I can still voice my opinion as I've thought about it and put some work in to it. And you like controversy.
I've been very fortunate to have travelled to many interesting places around the globe to observe birds. Many of those experiences and birds were unforgettable but I got just as big a kick last year out of finding a Barred Warbler down the road in brambles, as finding a Beautiful Nuthatch in a north-east Indian cloud forest. Well, not really, that's a lie. A big lie actually. (A lie like saying I find Vernon Kay tolerable or that I find people who keep a list of Bird Forum members they've seen in the 'field' anything less than creepy) but it's a bigger kick than that obtained after driving miles to see someone else's Barred Warbler. But substitute Radde's for Barred and I've got an argument I reckon! And the sight of a Sabs Gull or Bal. Shear going past me without 20 other people to find or identify it first really was thrilling. One thing I did find especially tiring to keep bumping into people looking for a bird I'd pagered like a Yellow-browed Warbler, Great Grey Shrike, even Ring Ouzels! etc when by putting in just a modicum of effort those people had a fighting chance of finding at least some birds of their own of similar 'rarity' value. Even more so when they say 'Well,it was on the pager earlier...' I'd rather put my face in a box of angry wasps than get any more of that..
I know many people don't have the chance to bird a great place like east or north Norfolk on a weekly or even regualr basis but surely when you do, why waste it going from one used scarce bird to the next? I tried this a few weeks back and the word I feel best described my feelings halfway through the day was 'souless'; I wasn't finding anything, certainly wasn't haven't to identify anything, so where was the buzz? There wasn't one. By just doing a 'circuit' of pagered birds you're missing out on the real experiences of birding – the long walks in quiet, wild and beautiful places; the time spent getting up close to wonderful flora and fauna and the real thrills of discovery, learning and genuine surprise. It may be the discovery of a new species for you, or something you weren't at all expecting to see, it maybe a new place full of surprises or that fresh insight into the identification of a species you weren't so hot on. And you never know - it could even be a rare bird! 
Good luck to all those searching for their own birds this year – see you at the next wc sparrow!
If you're offended by all of this, don't panic. You wont be alone. It probably means you're normal.