British Birds Rarities Committee

From time to time, BBRC has re-reviewed records that it previously accepted, to ensure they are acceptable in the light of improved knowledge of the species in question.[53] These reviews are carried out on a species-by-species basis. Old World warblers have proved particularly in need of re-review. A review of greenish warbler records was initiated in 1983.[54] The purpose of this review was to establish whether records, particular those in late autumn and winter, of drab grey Phylloscopus warblers, which had previously been accepted as greenish warbler, were in fact this species, or were common chiffchaffs of the Siberian race tristis. 48 records between 1958 and 1970 were examined. Of these, 20 were rejected.[55] A review of Arctic warbler records was begun in 1991,[56] with the aim of determining whether any greenish warblers had been mistakenly accepted as Arctics.[57] The review was completed in 1994,[57] although as of 2009, the results had not been published.

Greenish warbler, a species with a history of misidentification

A review of spectacled warbler records was initiated in 1984.[58] This review resulted in the species being removed from the British list; of the three accepted records, one, at Spurn, Yorkshire in 1968, was re-identified as a first-year female subalpine warbler, while descriptions of the other two, at Porthgwarra, Cornwall in October 1969 and on Fair Isle in June 1979, were not considered sufficiently watertight to permit their continued acceptance.[59] Spectacled warbler has since been re-added to the British list following an individual at Filey, Yorkshire in 1992,[60] and there have been further subsequent records.[61] In the late 1990s, BBRC reviewed some of the accepted records of moustached warbler, and concluded that one, from Sussex in 1979, was unacceptable,[62] but that one other, from Buckinghamshire in 1965, should stand.[63] Two further records, from Hampshire in 1951 and Kent in 1952, were reviewed as part of the 1950–1957 review (see below), and found to be unacceptable.[43] Following these rejections, the Buckinghamshire record, and the remaining record, a breeding pair in Cambridgeshire in 1946, previously accepted as Britain's first, were scrutinised by the BOURC and found to be unacceptable, leading to the removal of moustached warbler from the British list; it has not re-occurred.[64]

A review of olivaceous warbler records commenced in 1986,[65] and continued through the 1990s. The results of this review were published in 1999: six of the previously accepted records were rejected as not meeting modern identification standards.[66] In 2003, following the split of olivaceous warbler into two species, the accepted records were all reviewed again to ascertain which of the two they were—all nine proved to be eastern olivaceous warblers.[67] Following the split of Bonelli's warbler into two species, the committee reviewed all the 121 accepted records, and concluded that 51 were western and two were eastern; for the remainder, not enough evidence was available to make a firm decision.[68] The committee had previously stated that it would regard as western Bonelli's warbler all except proven eastern Bonelli's warblers,[69] however, this announcement rescinded that decision. In 2003–04, all desert warbler records were reviewed, and it was concluded that all were referable to the newly split Asian desert warbler, rather than African desert warbler.[70]

American golden plover, one member of a closely related and difficult-to-identify species pair

A review of American and Pacific golden plover records was begun in 1991,[56] with the purpose of evaluating whether any individuals previously accepted as "either American or Pacific" could now be definitely assigned to one species or the other (and vice versa). The results (a small decrease in the number of accepted American golden plovers, and a small increase in the number of accepted Pacifics) were published in the committee's report for 1996,[71] with a comment that a detailed paper on the subject was being prepared, although as of 2009, this has not been published. A review of isabelline shrike records commenced in 1986.[72] This review, the results of which were published in 1989,[73] established a racial identification for a number of adult isabelline shrikes previously accepted to species level. A further review, with the same aim, was begun in the late 1990s. A preliminary set of results of this review was published in 2003;[74] four previously accepted individuals were rejected, including one, in Cambridgeshire in 1978, which is now thought have been a hybrid with red-backed shrike. The full results of this second review were published in 2007;[75] some of the previous racial attributions were withdrawn, but the committee felt able to confidently assign a race for a number of more recent individuals, although it stressed that this could only be done with adult birds (the committee's 2005 report mentions that a further article is in preparation). A review of black-eared wheatears was conducted in 2002–04, with the aim of assigning individuals to the eastern and western races where possible; this was possible with nine records; both western hispanica and eastern melanoleuca were shown to have occurred.[76]

A review of semipalmated sandpiper records took place in the 1970s, resulting in seven of the twelve records being rejected.[77] A review of black-headed wagtail records was initiated in 1983.[78] The results were published in 1994 and 1995, and nine previously accepted records were judged to be unsound, due to possible confusion with grey-headed wagtail.[79] A review of rufous turtle dove records took place in 1994, and concluded that three of the eight accepted records should no longer stand.[80] A review of lesser kestrel records, begun in 1994,[81] and completed in 1995, concluded that six accepted records of this species should no longer be regarded as acceptable. Five of the six were from autumn, whereas the overwhelming majority of records the committee continued to accept are from the spring/summer period.[82] All 24 spring records of Siberian stonechat were reconsidered in 2002–04, in the light of new information on the variability in appearance of European stonechats in spring; the committee decided that all but five should remain accepted.[83] In 2003, the committee revised its assessment criteria for male pine buntings, redefining some birds previously considered hybrids as acceptable, but requiring an overall greater level of precision in descriptions, and reviewed past records in the light of these changes.[84]

As of 2017, the following reviews are underway: a review of past records of Macaronesian shearwaters,[85] reviews of all claimed Nearctic cackling goose records, a review of great white egrets to establish if any are of the Nearctic race,[86] a review of sandplovers,[86] a review of records of the eastern race of common redstart,[86] a review of Orphean warbler records aimed at determining the race of each,[86] and a review of subalpine warblers to determine which individuals are ascribable to the race albistriata.[87] It has also been suggested that reviews should be conducted of records of great snipe, as older records show a very different temporal occurrence pattern than more recent birds,[88] the large numbers of gull-billed tern records from the English south coast from the 1960s,[89] and desert wheatears, to establish racial identifications.[90]

Least tern, a species seen just once in Britain

Most records received by the committee are processed within a year and published in its annual report in British Birds.[5] Some records prove problematic, and for some species, it has taken the committee many years to come to a decision. This has particularly been the case where the species or subspecies in question was new to Britain—examples include northern harrier (Britain's first, in Scilly in 1982, accepted in 2007),[91] long-toed stint (Britain's first, in Cornwall in 1970, accepted in 1994),[92] least tern (Britain's first, and to date only record, accepted in 2005, after first occurring in 1983),[93] black lark (Britain's first, from Spurn, Yorkshire in 1984, accepted in 2004 after a second set of notes came to light),[94] Sykes's warbler (the first three records, from 1959, 1977, and 1993, accepted in 2003),[95] Iberian chiffchaff (the first two records, from 1972 and 1992, accepted in 2000),[96] and Hume's leaf warbler (the first 27 records, the earliest from 1966, accepted in 1998).[97] Occasionally, decisions have been delayed due to non-ornithological factors, such as the loss by the Royal Mail of a file on Britain's first lesser short-toed lark.[98]

The first three field records of Blyth's pipit, including an atypical pale individual on the Isles of Scilly,[99] proved difficult, but following the occurrence of trapped individuals, on Fair Isle in 1993 and Suffolk in 1994, these were accepted.[100] Some records of citrine wagtail[101] and short-toed treecreeper[102] were accepted only after prolonged consideration. Prior to the publication in 1984 of Jonsson and Grant's stint identification paper,[103] a number of stints (Calidris) proved difficult to assess; a paper covering four such cases was published in 1986.[104] It included accounts of a bird on Fair Isle, originally thought Britain's first red-necked stint that turned out to be a sanderling; and a bird in Suffolk, The "Felixstowe stint", which most observers at the time believed was a western sandpiper, but was in fact a semipalmated sandpiper. A previous paper[77] details four early claims of red-necked stint, none of which were acceptable.

As of 2007, records of Wilson's snipe (from 1985 and 1998),[86][105] elegant terns (from 2002),[86] a number of eastern whitethroats and lesser whitethroats,[86] and several apparent North African common chaffinches,[86] are still under consideration.

BBRC has had particular problems with a number of rare seabirds. The "Chalice petrel", a dark-rumped storm petrel seen and photographed in the Southwest Approaches in 1988, and believed by its observers to be a Matsudaira's storm petrel, was eventually rejected as other similar species could not be ruled out.[106] Martin Garner and Killian Mullarney subsequently wrote a critical review of this decision, arguing that the evidence points to the bird having been a Swinhoe's storm petrel, the only dark-rumped storm petrel species otherwise recorded in the North Atlantic.[107] They argued that the Seabirds Advisory Panel's assessment of the record was at fault, and a critical reappraisal of the evidence should have been prompted by the (then relatively recent) discovery in the North Atlantic of Swinhoe's storm petrel, and that the committee was instead too heavily swayed by the views of a single expert.

A petrel seen from Dungeness, Kent and believed by its observers to be Britain's first herald petrel was rejected, although the committee noted that the bird was clearly "an amazing seabird".[108] This decision sparked a number of letters to British Birds questioning whether the committee's stance is too strict.[109] Fea's petrel is now officially accepted as having occurred, but for many years, the identification of these birds was accepted only as Fea's/Zino's/soft-plumaged petrel, followed by a period where they were referred to Fea's or Zino's; however, following BOURC acceptance of two birds in Scilly waters as Fea's petrels, BBRC published a paper arguing that all birds are likely to have been Fea's.[110]

The occurrence in Britain of southern (i.e. south polar/brown) skuas is also unresolved. A series of reports of south polar skua, from 1982 to 1993, were all eventually rejected after being assessed for several years.[111] Two other birds (from the Isles of Scilly in 2001, and Glamorgan in 2002 have been accepted (by the BOURC) as belonging to one or other of these two species,[112] while a bird from Dorset in 1996 remains under consideration.[113]

In 1996, Alan Vittery raised the question of whether the level of detail required by the committee for a description to be acceptable was too high.[48] Similar points were made by Keith Vinicombe and Mike Pennington in 2001. In the light of the rejection of a record of Blyth's reed warbler in Shetland in 1997, Vinicombe and Pennington wrote to British Birds to question the decision. They suggested that the committee was becoming too focussed on minutiae in assessing bird descriptions, ignoring more obvious evidence, Vinicombe saying that "the Committee has prevaricated to the point where it 'cannot see the wood for the trees'".[114] David Walker and Owen Leyshon, David Ferguson, and Andrew Duff[109] have criticised the committee on similar grounds in relation to its approach to the assessment of rare seabirds, citing the Dungeness herald petrel claim as an example. Vittery, and Moss Taylor[115] both expressed concern that BBRC was adopting too strict an approach for records of birds seen only by their finder.

In 1998, BBRC explained its approach to the assessment of single-observer records. The committee explained that while it understood that geographical and social circumstances make it likely that some people are more likely to find rare birds on their own, it is "very cautious about observers with a high proportion of single-observer records" and that its policy is to watch patterns closely and review those observers' past records on a regular basis.[116] This approach has attracted criticism. Former BBRC chairman Ian Wallace and others have written about the subject in Birdwatch magazine. Wallace believes that the committee has a blacklist of observers, from whom it automatically rejects records unless there are other observers able to corroborate the sighting. He mentions two specific observers, both of whom live in remote parts of northern Scotland.[117] Ken Shaw, a former BBRC member, has claimed that BBRC would not accept a single-observer record of a species new to Britain without photographic evidence, regardless of the track record of the observer.[118] Graham Bell, another former member, writing in response to Shaw's article, has accused the committee of adopted unfounded suspicions, arguing that just because a competent observer moves to an underwatched part of the country, their abilities do not change.[119] One of the observers who Wallace claimed was blacklisted, Alan Vittery, also contributed to the debate, stating that he had been informed by the BBRC that they would not consider any single-observer record he submitted, unless supported by a photograph. Vittery contrasted the BBRC's attitude with that of other national rarities committees, arguing that the result of the approach is to distort rarity statistics.[120] Vittery invited the BBRC to reply in public, but this request was declined.[117]

The BBRC conducted a detailed review into the controversial identification of a curlew seen at Druridge Bay in Northumberland in 1998, coming to the conclusion that it was, as had been believed by many observers, a first-summer slender-billed curlew. This identification was accepted by the British Ornithologists Union's Records Committee, leading to the addition of this species to the British List.[121] The record was reviewed in 2014, and, after a split decision by both the BBRC and the BOURC, the record was found not proven and subsequently removed from the British List.[122]

A subcommittee was set up in 1997 to undertake a review of rare bird records from the years immediately prior to BBRC's establishment. The purpose of the review was to ensure that all records from 1950 onwards (the cut-off date for Category A of the BOU British List of birds) have been subjected to a similar level of scrutiny. Not all of the 1,100 records of species considered to be rarities at that time were assessed, but only those related to species not recorded more than 100 times by 1997, as well as a few records of less rare species under particularly unusual circumstances, which were termed "sore thumbs".[43] Much of the original documentation was unavailable for the review, as it had been lost, and so for many records, the review was based solely on published accounts of the birds.[43] The most notable outcome of this review was the reidentification of a frigatebird record from Tiree in 1953. Previously identified as a magnificent frigatebird, the BBRC review concluded that the bird was in fact an Ascension frigatebird, the only individual of this species ever identified in Europe (Walbridge, Small & McGowan 2003).[123] The full results of the review were published in 2006.[43] Of the 126 records reviewed, 37 were rejected as unacceptable. These included a claimed white-tailed eagle, which broke into a chicken-run in a garden and stole a chicken, three little crakes, three Eurasian scops owls, the only late December record of tawny pipit, three black-eared wheatears, a record of two White's thrushes together in April, a spring lanceolated warbler, two moustached warblers and a pine grosbeak. Furthermore, issues were found with the identification of Britain's first western sandpiper, on Fair Isle in 1956,[124] and these led the BOURC to reject this record.[125] The western sandpiper has been recorded several times subsequently in Britain however, and remains on the national list.[125] The subcommittee's final report also hints at the prospect that some records from immediately prior to 1950 may be incorrect; because these fell outside the timeframes of the review they were not reassessed.[43]

Only a single known hoax involving a record submitted to BBRC has become public. In autumn 1994, Nigel Pepper, a birdwatcher from Essex, claimed to have recorded a hermit thrush in a garden in Chipping Ongar. Doubts about the record were raised in Birdwatch and BBRC reviewed the record in 2002, but decided that it should stand. In 2009, Nigel Pepper came clean and revealed in Birdwatch magazine (Birdwatch 204: 46-47) that the record was actually a hoax, made in protest at perceived suppression of rare bird records in the county. He revealed that the Hermit Thrush in question was actually photographed in Canada on a recent birdwatching trip.