Report on rare birds in Great Britain in 2002 M. J. Rogers and the Rarities Committee his is the forty-fifth annual report of the addition, the first British Snowy Egret Egretta British Birds Rarities Committee and it thula remained into another year and there are Tprovides details of the records which second mentions of Red-billed Tropicbird have been assessed by BBRC for the year 2002, Phaethon aethereus, Lesser Sand Plover along with additional, outstanding records from Charadrius mongolus and Tree Swallow previous years. To enhance the overall accuracy Tachycineta bicolor. Other highlights of the year of the report, we have, for the first time, invited must include not one but two Oriental Turtle County Recorders and bird report editors to Doves Streptopelia orientalis, after an absence of check a draft version. Although the response more than 25 years, and the first Lesser Kestrel was not complete, for a variety of reasons, we Falco naumanni since 1992. see this as a positive move towards greater co- Rarity-minded readers will note that there operation between BBRC and those who submit are several obvious omissions from the report – records to us. We hope that such collaboration no ‘orange-billed’ terns Sterna or ‘brown’ skuas will improve steadily towards a point where Catharacta, for instance – which merits explan- errors and omissions are few, and the content of ation here. BBRC is analysing the occurrence the report remains consistently accurate and and descriptions of ‘orange-billed’ and ‘Elegant thorough. S. elegans-like’ terns, both in Europe and along This year’s report gives details of decisions the Atlantic seaboard of North America, to made on some really great birds, including no investigate whether any common pattern of fewer than six species – Ascension Frigatebird dates or plumage characters can lead us towards Fregata aquila, Allen’s Gallinule Porphyrula a sensible approach when assessing these alleni, Macqueen’s Bustard Chlamydotis mac- records. Similarly, we are attempting to develop queenii, ‘Caspian Gull’ Larus (cachinnans) a rational stance for assessment of ‘brown’ cachinnans, Eastern Olivaceous Warbler Hippo- skuas. While a combination of DNA, biometrics lais pallida and Sykes’s Warbler Hippolais rama and a full description may clinch the identifica- – which, for one reason or another, make their tion of the bird at Aberavon, Glamorgan, in first appearance in a BBRC report. The detective February 2002 (as Brown Skua C. antarctica), work required to add Ascension Frigatebird to and DNA analysis of samples taken from the the British List has already been reported in individual on St Agnes, Scilly, in October 2001 detail (Brit. Birds 96: 58-73), while Allen’s prove it too is part of the Brown Skua group Gallinule was elevated to Category A following (see Brit. Birds 95: 538), dealing with sight-only the capture of one at Portland, Dorset, just as records remains problematic, as those who saw the only previous record, in January 1902, the Dorset and Devon ‘brown’ skuas in January passed its centenary. Macqueen’s Bustard and 2000 will testify. For such birds, separation of the two warblers appear here as the result of Great Skua C. skua from South Polar Skua C. continuing taxonomic research, conferring maccormicki and Brown Skua in plumages other species status upon forms previously considered than adult breeding would seem impossible. subspecies: something which we will surely see Surely, however, we should not lose these more of in the next few years. The long-antici- records and there must be a way forward; we pated addition of Sykes’s Warbler to the British just need to establish the criteria to get there. List involves, for the time being, only those On a more upbeat note, we have now agreed the records concerning trapped individuals. In criteria required for identification and accep- 542 © British Birds 96 • November 2003 • 542-609 Report on rare birds in Great Britain in 2002 tance of Sykes’s Warbler in the hand. This has Gallinago (gallinago) delicata but these appear enabled us to carry out a review of some to be so limited that we are not clear whether records previously accepted as Booted Warbler they are of use in the field. It would be fair to H. caligata, and the results are published here. A say that with these projects, and examination of review of field identification criteria is all the large white-headed gull records, it has underway. Although no longer a rarity, we not been a quiet year! publish the first details of ‘Caspian Gull’ in A quick glance at the Wilson’s Storm-petrel Britain. BBRC would be pleased to review any Oceanites oceanicus records may raise some well-documented claims, preferably with sup- queries. Two of the records are from ‘Scilly’ porting photographs, made prior to 31st while the remainder are ‘At sea’. This is because, December 1999. As many observers are now historically, records within three nautical miles familiar with this distinctive taxon, its true from shore are regarded as having the same status in Britain is becoming clearer, but one status as birds seen from the adjoining land. wonders whether it has always been relatively Birds farther out are regarded as ‘At sea’. common, or whether a new pattern is emerging. Although this may seem arbitrary, it helps to BBRC has also been investigating the difficult distinguish birds which may have been visible business of subspecies identification, particu- from land, and changing this system now would larly of forms which have the potential to occur create problems when examining the historical in Britain. This can be a minefield of missed records dealt with in this way. opportunities and false starts, as not only is Following last year’s request, more records much of the background information incom- are being submitted by e-mail (to plete, but the taxonomic position of some races [email protected]) and we greatly is also in a state of flux, in particular where welcome this (with, of course, copies to the these occur in poorly studied regions of the relevant County Recorder). We also welcome Palearctic such as Central Asia. As a result, we digital photographs submitted in the same way, are now in a position to assess many little- but require images to be reasonably small or known subspecies and emerging species. We compressed (preferably in .jpeg format) so that have now completed our analyses of the downloading times are minimised. To ensure Orphean Warbler Sylvia hortensis complex, sep- that our database of records remains accurate, aration of Eastern Hippolais pallida and we would request observers to provide their full Western Olivaceous Warblers H. opaca, and the initials so that attributions can be applied con- badius form of Woodchat Shrike Lanius senator, sistently, year on year. The proofreading of the and details of these will be published shortly. As report by County Recorders, mentioned earlier, an example of the unexpected problems we is tangible evidence of the burgeoning e-mail face, we thought we were close to finalising our correspondence between BBRC and recorders. analysis of the Isabelline Shrike L. isabellinus Any recorders or editors who have not yet been complex, but may now have to completely re- involved in this process but would like to par- evaluate this if the position of the form karelini ticipate in future should send an e-mail to is changed. We are also close to completing our [email protected]. We are particularly reviews of spring ‘Siberian Stonechats’ Saxicola grateful to Judith Smith for her help in fostering torquata maura, Grasshopper Warblers these links. Readers are reminded that they can Locustella naevia of the eastern race straminea, find out more about records committees Reed Warblers Acrocephalus scirpaceus of the throughout Europe by visiting the Association eastern race fuscus, Subalpine Warblers S. cantil- of European Rarities Committees website, at lans and Desert Warblers Sylvia nana, and have www.AERC.be. established guidelines for the subspecific identi- BBRC wishes to thank the full network of fication of Common Redstarts Phoenicurus County Recorders and Bird Observatory phoenicurus of the eastern form samamisicus, Wardens and their respective committees, with the Lesser Whitethroat S. curruca complex in whom it has worked closely to produce this Asia, including the so-called ‘Desert Lesser report, and especially those who have checked a Whitethroat’ S. (c.) minula, and Common draft version. BBRC also readily acknowledges Chaffinches Fringilla coelebs of the African form everyone who finds a rarity and makes the africana. We have also finalised a full analysis of effort to submit their record. Without such the identification criteria for ‘Wilson’s Snipe’ commitment this report would simply not be British Birds 96 • November 2003 • 542-609 543 Report on rare birds in Great Britain in 2002 produced. It is inevitable that, despite our best Steve Mlodinow, Will Russell, Ben Sheldon, efforts, not all records submitted appear in this David Sibley, David Spector, Keith Vinicombe, report. Some arrived too late for circulation to Steve Votier, Angus Wilson and, in particular, be completed in time, while other difficult Bill Clark, Dick Forsman and Ron Pittaway for records are currently being reviewed and recir- their input on difficult records this year, and culated. Comparing the records we received Keith Naylor for his extensive assistance with with those reported to the various bird infor- historical data. mation services suggests that there are less than Our sponsors, Carl Zeiss Ltd, continue to 30 records missing for 2002. We continue to support our work, and we remain enormously encourage the finders to submit these records grateful for the financial contribution they for review, so that these reports can be made as make.