Artigo Acesso aberto Revisado por pares

British Ornithologists’ Union Records Committee: 31st Report (October 2004)

2005; Wiley; Volume: 147; Issue: 1 Linguagem: Inglês

10.1111/j.1474-919x.2005.00394.x

ISSN

1474-919X

Tópico(s)

Species Distribution and Climate Change

Resumo

This report covers the period October 2003 to September 2004 and is the fifteenth to follow publication of the most recent Checklist of Birds of Britain and Ireland (6th edition, March 1992). The 30th Report appeared in Ibis 146: 192–195. The Checklist is available from the BOU office and specialist bookshops, price £2 (UK) and £3 (overseas) (prices inc. p & p). During the year, progress continued to be made on a seventh edition of the BOU's Checklist of Birds of Britain. The BOU website includes a continually updated version of the British List, press releases and lists of recent decisions and files in circulation. The website is for information purposes only and is not an official document or part of the permanent record. Announcements of changes to the British List do not come into effect until published in Ibis. Since publication of our last report, the BOURC Taxonomic Sub-committee (TSC) has published its latest recommendations relating to the British List (Sangster et al. 2004. Taxonomic recommendations for British birds: second report, Ibis 146: 153–157). These came into immediate effect with the publication of that paper and will not be repeated here. During the course of its work, the Committee is constantly reviewing its operating guidelines and policies. One of the main tasks of BOURC is to assess the likelihood of a species occurring naturally in Britain. This is done by looking at, among other things, the location of the individual, time of appearance, weather patterns leading up to its appearance, supporting cast of species, age and condition of the individual, migratory patterns and vagrancy potential of the species. The record is then assessed against the status of the species in captivity and the escape likelihood. Ship assistance is not necessarily a bar to inclusion on the British List, provided the bird was not confined, sheltered or provisioned during its journey. If the bird is found dead on board, we need to consider whether it may have died in British waters. Finally, we need to consider if the species might be capable of reaching Britain without ship assistance. BOURC's policy on ship assistance was never meant to allow non-migratory species or port-to-port transportees to be admitted to the British List. The Committee recently amended the wording of its policy on ship assistance to reflect better the Committee's views, as follows: That the species might be expected to arrive in Britain naturally and without ship assistance given favourable circumstances (i.e. the species is migratory and its migratory route matches that of other species believed to occur naturally). The wording of Category E has been reworded (see below) explicitly to cover records of birds arriving here as a result of ‘human-assistance’. Category definitions were reviewed following a joint BOU/Joint Nature Conservation Committee (JNCC) conference in 1995. The published review (British Birds 91: 2–11, Ibis 141: 175–180) outlined the newly adopted category definitions. The Committee recently reviewed several aspects of the categories again. The current definitions are reproduced below with italicized comments indicating the changes that have been made to the wording or the implementation. Species that have been recorded in an apparently natural state at least once since 1 January 1950. No change. Species that were recorded in an apparently natural state at least once between 1 January 1800 and 31 December 1949, but have not been recorded subsequently. Definition changed to include a start date and dual categorization with Category D now recognized. Species that although introduced now derive from the resulting self-sustaining populations. (This wording was introduced in the Committee's 29th report (Ibis 145: 178–183)). Simplification of the wording without changing the meaning; also minor changes to the wording of the subcategories below. Naturalized introduced species – species that have occurred only as a result of introduction, e.g. Egyptian Goose Alopochen aegyptiacus. Naturalized established species – species with established populations resulting from introduction by Man, but which also occur in an apparently natural state, e.g. Canada Goose Branta canadensis. Naturalized re-established species – species with populations successfully re-established by Man in areas of former occurrence, e.g. Red Kite Milvus milvus. Naturalized feral species– domesticated species with populations established in the wild, e.g. Rock Dove/Feral Pigeon Columba livia. Vagrant naturalized species– species from established naturalized populations abroad, e.g. possibly some Ruddy Shelducks Tadorna ferruginea occurring in Britain. There are currently no species in Category C5. Species that would otherwise appear in Category A except that there is reasonable doubt that they have ever occurred in a natural state. Species on Category D only do not form any part of the species totals and form no part of the British List. (This wording was introduced in the Committee's 29th report (Ibis 145: 178–183)). This category was previously defined as ‘species that would otherwise appear in Categories A or B’ but has been reworded to allow for dual categorization with Category B. Species that have been recorded as introductions, human-assisted transportees or escapees from captivity, and whose breeding populations (if any) are thought not to be self-sustaining. Species in Category E that have bred in Britain are designated as E*. Category E species form no part of the British List (unless already listed within Categories A, B or C). The words ‘human-assisted’ now qualify ‘transportees’ to clarify that ship-assisted vagrants may qualify for Category A provided that they are not fed, watered or receive any other direct human intervention during their journey. Having responsibility for the British List, the BOURC is required to review those non-native species that may establish self-sustaining populations and be eligible for elevation to Category C. During the year, a more formal system for carrying out this function was agreed with the Joint Nature Conservation Committee (JNCC). BOURC will review available data relating to Category E* species (i.e. those species that have escaped or been released and are now breeding in the wild) to determine whether a species can be considered ‘self-sustaining’. Any species deemed to have a self-sustainable population in Britain will be subject to an ‘alert’ to JNCC, who will then review the available information and assess, with other bodies, any conservation concerns that may arise. On completion of the ‘conservation concern’ review, those species deemed to pose no conservation threat to other flora and fauna will be admitted to Category C. A review of the status of species that may have the potential for elevation to Category C has already begun. As a corollary to this work, BOURC, together with the Rare Breeding Birds Panel (RBBP), issued a joint press release appealing for observers to submit records of non-native species to county recorders (see press release of 19 August 2004 at http://www.bou.org.uk/recnews.html). Following the separation of the British and Irish Lists (Ibis 141: 175–180) it became necessary, for species that had been recorded in Ireland prior to being recorded in Britain, to establish acceptable first British records for these species. Post-1950 records were detailed in our 29th Report (Ibis 145: 178–183) and the Committee continued with this process during the current year by considering pre-1950 records. Six of these first records have now been confirmed (see below) but the Committee is still considering which record of Two-barred Crossbill Loxia leucoptera may be acceptable as the first for Britain. The following changes have been made to the British List: One, Earsham, Norfolk, 10 April 1858, specimen preserved in Castle Museum, Norwich (Zoologist 16: 6096–7). This becomes the first British record following the review of ‘post-Irish firsts (pre-1950)’. Add to Category C; this species now has dual categorization of AC. This follows the establishment of an introduced and now self-sustaining population (Bainbridge et al. 2003. Re-introduction of White-tailed Eagles (Haliaeetus albicilla) to Scotland. In Thompson et al. (eds) Birds of Prey in a Changing Environment. Edinburgh: The Stationery Office). One, Hawk's Wood, Cornwall, 4 December 1860, collected but specimen not extant (Zoologist 19: 7311). This becomes the first British record following the review of ‘post-Irish firsts (pre-1950)’. One, Buckland, near Dover, Kent, May 1877. Found injured, later died, specimen now in Dover Museum (Zoologist 35: 298). This becomes the first British record following rejection of one near York, November 1867, as one of the ‘Tadcaster Rarities’ (Ibis 145: 182). Add to Category A. One, Portland, Dorset, 10 February 2002. Found moribund, photographed, specimen donated to the Natural History Museum (Birding World 15: 58–59). The species was previously included in Category B on the basis of one off Hopton, Norfolk, January 1902. Following the recommendations of the BOURC TSC (Ibis 144: 707–710) to elevate Macqueen's Bustard C. macqueenii to specific status, the Committee assessed all five British records of Houbara Bustard C. undulata and accepted all as C. macqueenii. Four of these records were pre-1950 (the first being in 1847, Ibis 146: 192–195), but one, Suffolk, November/December 1962, allows Macqueen's Bustard to be added to Category A of the British List. Houbara Bustard is removed from the British List. One, Loch Lomond, Dunbartonshire, April 1850, collected but specimen not extant (Zoologist 9: 3117–3118). This becomes the first British record following the review of ‘post-Irish firsts (pre-1950)’. Add to Category A. Second-summer, Dungeness, Kent, 5–7 May 2003, sight record, photographed and video-recorded (Birding World 18: 199–202). Monotypic. Breeds in the Mediterranean basin, wintering there and south along the coast of northwest Africa as far as Senegal. First-winter, between Out Skerries and Whalsay, Shetland, 28 April 1936. Captured exhausted at sea, later died, photograph of mounted specimen extant but specimen now destroyed (Brit. Birds 35: 276). This becomes the first British record following rejection of one, Yorkshire 1846 or 1847, which was one of the ‘Tadcaster Rarities’ (Ibis 145: 178–183). One, Horsey Mere, Norfolk, 17 May 1853, collected but specimen not extant (Zoologist 11: 3911). This becomes the first British record following the review of ‘post-Irish firsts (pre-1950)’. One, Clintburn, near Bellingham, Northumberland, 5 August 1870, specimen in Hancock Museum, Newcastle-upon-Tyne (Zoologist 28: 2344). This becomes the first British record following the review of ‘post-Irish firsts (pre-1950)’. One, Lawrenny, Stackpole Court, Pembrokeshire, autumn 1832, specimen in Natural History Museum (Proc. Zool. Soc. Lond. 1: 26). This becomes the first British record following the review of ‘post-Irish firsts (pre-1950)’. One, Skewjack, Cornwall, 16 May 1981. Sight record, photographed (Brit. Birds 75: 512). This becomes the first British record following the rejection of one in Denbighshire in 1973 (Ibis 145: 178–183). Add to Category A. Male, Spurn Point, Yorkshire, 27 April 1984, sight record, only positively identified and submitted for verification 15 years after its occurrence. Monotypic. Breeds on the steppes of southern Russia and Kazakhstan; dispersive and perhaps nomadic outside breeding season (Brit. Birds 97: 558–625). This species was previously on the British list but was deleted as one of the Hastings Rarities (Brit. Birds 55: 299–384, Ibis 105: 289–291). Records of birds on the Isles of Scilly, 3–4 October 1961 and 30 September–2 October 1962, which had been submitted as the only British records of this taxon, newly elevated to specific status (Ibis 144: 707–710), were reviewed by the Committee but found to be insufficiently substantiated. This species is therefore removed from the British List. One, Fair Isle, Shetland, 29–31 August 1959, trapped (Brit. Birds 53: 409–431). Following the recommendation of the TSC (Ibis 144: 707–710), BOURC has accepted the elevation to species status of H. rama (formerly considered a race of Booted Warbler H. caligata). The taxon was established on the British List on the basis of a record from Shetland in 1993 (Ibis 142: 177–179). All British records of Booted Warblers were reviewed by the British Birds Rarities Committee (BBRC) and subsequently by BOURC to establish if any others were identifiable as Sykes's Warbler. Several were indeed found to be referable to H. rama and the record detailed above now becomes the first for Britain. Add to Category A. One, first-winter, Howmore, South Uist, Western Isles, 3–4 November 2000. Sight record, photographed (Birding World 13: 454–457). Polytypic; five races recognized. The Committee felt that the race involved was probably erythronotus, which is migratory in the northern part of its range in Kazakhstan and Turkmenistan, but could not entirely rule out caniceps although the latter's range in the Indian peninsula made its occurrence most unlikely. Add subspecies badius Hartlaub to Category A. Adult male, Portland, Dorset, 10 May 1986. Sight record (Brit. Birds 80: 563). Breeds only on the Mediterranean islands of Corsica, Sardinia and the Balearics. With the addition of Audouin's Gull, Black Lark and Long-tailed Shrike to Category A, the deletion of Western Olivaceous Warbler from Category A, and the transfer of Allen's Gallinule and Macqueen's Bustard from Category B to Category A, the British List now stands at 567 species. The totals do not include ‘soft-plumaged’ petrels Pterodroma mollis/P. madeira/P. feae as the birds were not identified to species level (Ibis 134: 380). However, the Committee is currently actively considering whether any records from this species group may be assigned to an individual species. Species in Categories D and E do not form part of the British List. The following have also been considered: The record of one taken on the Bass Rock, May 1831 has been thoroughly reviewed by the Committee and rejected on a majority decision. The Committee has considered whether the nominate race of Lesser Black-backed Gull L. f. fuscus, colloquially known as Baltic Gull, should be retained on the British List. On the basis of a Finnish bird ringed as a chick in July 1978 and recovered in Suffolk in October 1981, it was decided that it should but the Committee wish to draw the attention of observers to the extreme rarity of this taxon in Britain. BOURC are still considering the records from North Yorkshire in 1837 and 1908 but agreed with BBRC that the record off Walney, Cumbria, in 1990 must be considered unproven. Investigations are continuing into the identity of the bird seen in East Sussex, 1983–90, and believed to be of the race antillarum. The context of the recording noted in the 30th Report (Ibis 146: 192–195) is being investigated while the TSC is still considering the status of the taxon. The only British record, Northumberland, 5 October 1856, is still under review. Following a review of the records of this species by BBRC, the Committee is considering which of these may constitute an acceptable first for Britain. There have been no additions or modifications to the Manx List during the period under review. Bradshaw, C. & Meek, E.R. 2004. Comments on ‘Canvasback in Kent: new to Britain’. Brit. Birds 97: 142. Bradshaw, C. & Meek, E.R. 2004. Comments on ‘Red-billed Tropicbird: new to Britain’. Brit. Birds 97: 237. Bradshaw, C. & Meek, E.R. 2004. Comments on ‘Snowy Egret in Argyll & Bute: new to Britain’. Brit. Birds 97: 275. Bradshaw, C. & Meek, E.R. 2004. Comments on ‘American Coot in Kent: new to Britain’. Brit. Birds: 97: 447. Garner, M., Lewington, I. & Slack, R. 2003. Mongolian and Lesser Sand Plovers: an identification review. Birding World 16: 377–385. Garner, M., Lewington, I. & Rosenberg, G. 2004. Stejneger's Scoter in the Western Palearctic and North America. Birding World 17: 337–347. Harrop, A.H.J. 2004. The soft-plumaged petrel complex. Brit. Birds 97: 6–15. Harrop, A.H.J. 2004. The ‘North American’ Peregrine in Britain. Brit. Birds 97: 130–133. McGowan, R.Y., Clugston, D.L. & Forrester, R.W. 2004. Identification and status of Scotland's endemic wrens and other endemic subspecies. Birding World 17: 71–75. Votier, S.C., Bearhop, S., Newell, R.G., Orr, K., Furness, R.W. & Kennedy, M. 2004. The first record of Catharacta antarctica in Europe. Ibis 146: 95–102. A considerable number of people assisted the Committee in its work during the course of the year and, with sincere apologies for any accidental omissions, the BOURC would like to extend our thanks to the following: Mark Adams, David Bolton, Ian Dawson, Steve Dudley, Errol Fuller, Baz Hughes, Nigel Jarret, Chris Keogh, Alan Knox, Cathy King, Stuart Ogilvy, Phil Palmer, Mike Pennington, Pete Rock, Mike Rogers, Brian Small, Didier Vangeluwe, Keith Vinicombe and Ian Wallace. During the year, Dr Roger Wilkinson retired (on rotation) from the Committee and his place has been taken by Dr Stephen Votier. Roger's knowledge of birds in captivity has been essential to the Committee and we are delighted that he has agreed to remain with us in a consultative capacity. The following served on the BOURC during the period covered by this report (expected year of retirement in parentheses): Eric Meek (Chairman) (2006) Tim Melling (Secretary) (2007) Martin Collinson (2009) Andrew Harrop (2007) Ian Lewington (2006) Bob McGowan (2008) Tony Prater (2005) Grahame Walbridge (2010) Steve Votier (2011) Roger Wilkinson (2004) Colin Bradshaw (BBRC Representative)

Referência(s)
Altmetric
PlumX