Ibis (2011), 153, 883–892 Taxonomic recommendations for British birds: seventh report GEORGE SANGSTER,1,2* J. MARTIN COLLINSON,3 PIERRE-ANDRE´ CROCHET,4 ALAN G. KNOX,5 DAVID T. PARKIN,6 LARS SVENSSON7 & STEPHEN C. VOTIER8 1Department of Vertebrate Zoology, Swedish Museum of Natural History, PO Box 50007, SE–104 05 Stockholm, Sweden 2Department of Zoology, Stockholm University, SE–10691 Stockholm, Sweden 3School of Medical Sciences, Institute of Medical Sciences, University of Aberdeen, Aberdeen AB25 2ZD, UK 4CNRS-UMR 5175 Centre d’Ecologie Fonctionnelle et Evolutive, 1919 route de Mende, 34293 Montpellier Cedex 5, France 5University Museums, King’s College, University of Aberdeen, Aberdeen AB24 3SW, UK 6Institute of Genetics, University of Nottingham, Queen’s Medical Centre, Nottingham NG7 2UH, UK 7S:ta Toras va¨g 28, SE–269 77 Torekov, Sweden 8Marine Biology and Ecology Research Centre, University of Plymouth, Plymouth PL4 8AA, UK This paper is the seventh report of the Taxonomic • Bermuda Petrel Pterodroma cahow (monotypic) Sub-Committee (TSC) of the BOU Records Committee (BOURC) relating to the British List. Capped Petrel is in Category A of the British Species-level decisions are based on criteria out- List. lined by Helbig et al. (2002). The sixth report of the Sub-Committee was published by Sangster Water Rail Rallus aquaticus et al. (2010a). The Sub-Committee has been working with the Recent vocal and molecular studies indicate that Association of European Rarities Committees’ Water Rail consists of two distinct lineages (de Taxonomic Advisory Group, which has recently Kroon et al. 2008, Tavares et al. 2010). Two main published recommendations online (Crochet et al. call types have been recorded for Rallus aquaticus 2010). The reports of the BOURC and its TSC, aquaticus: a long and complex call (the ‘pig which are published in Ibis, remain the official squeal’), and a short and simple call, both repeated publications of the BOU. in series, whereas for Rallus aquaticus indicus, only a complex call type has been recorded, which is distinct from that of R. a. aquaticus (de Kroon Capped Petrel [Black-capped Petrel] et al. 2008). Preliminary playback experiments Pterodroma hasitata showed a lack of response of R. a. aquaticus to the Capped Petrel and Bermuda Petrel differ diagnos- complex calls of R. a. indicus, suggesting a biologi- ably in pattern and coloration of crown, hindneck cal significance for these differences (de Kroon et al. and rump, and uppertail-coverts (Brooke 2004, 2008). Phylogeographical analysis of mitochondrial Howell & Patteson 2008). Molecular phylogenetic and nuclear DNA sequences places R. a. indicus analysis further suggests that these are not closely in a separate clade from the clade containing related taxa (Jesus et al. 2009). Capped Petrel and R. a. aquaticus and Rallus aquaticus korejewi, and Bermuda Petrel are therefore best treated as sepa- further showed that these clades are strongly differ- rate species: entiated (Tavares et al. 2010). The two groups also • Capped Petrel Pterodroma hasitata (polytypic) differ in plumage (Cramp & Simmons 1980, de Kroon 1991, Taylor & van Perlo 1998). Water Rail is therefore best treated as two species: *Corresponding author. • Water Rail Rallus aquaticus (polytypic, with Email: [email protected] subspecies aquaticus and korejewi) ª 2011 The Authors Ibis ª 2011 British Ornithologists’ Union 884 Taxonomic recommendations for British birds: seventh report • Brown-cheeked Rail Rallus indicus (mono- Eurasian Whimbrels in Scandinavia (N. p. typic) phaeopus; Johnsen et al. 2010) and Eastern Asia Water Rail is in Category A of the British List. (Numenius phaeopus variegatus; Kerr et al. 2009), comparable with other pairs of sister species. We have combined the datasets of Hebert et al. Kentish Plover Charadrius alexandrinus (2004), Yoo et al. (2006), Kerr et al. (2009) and A recent study has documented morphological, Johnsen et al. (2010) and performed phylogenetic molecular and vocal differences between Kentish analyses to determine how Eurasian Whimbrels in Plover Charadrius alexandrinus alexandrinus and Scandinavia are related to those in Eastern Asia. Snowy Plovers Charadrius alexandrinus nivosus Mitochondrial DNA sequences of Hudsonian (Küpper et al. 2009). Kentish Plovers have longer Whimbrel clustered with strong support in a clade wings and tarsi than Snowy Plovers, although there that is sister to a clade formed by Eurasian Whim- is overlap of measurements. Female Snowy Plovers brels, but Scandinavian phaeopus and Eastern Asian can have various amounts of black in the head- and variegatus samples were very similar and did not breast-markings, sometimes making them similar form separate clades (Fig. 1). Numenius phaeopus to those of males, whereas in female Kentish alboaxillaris has not been included in any molecu- Plovers these areas are brown. Chicks of Kentish lar analyses but is presumed to be allied to the Plover have a dark central stripe on the upperparts, phaeopus ⁄ variegatus clade on geographical grounds. which is lacking in Snowy Plovers. Mitochondrial It is recommended that hudsonicus is treated as a DNA sequences (ND3 and ATPase) of Kentish separate species. Plover and Snowy Plover differ by 6.1% on average. • Hudsonian Whimbrel Numenius hudsonicus Mitochondrial DNA sequences and CHD-Z geno- (monotypic) types were more divergent between Kentish and • Eurasian Whimbrel Numenius phaeopus (poly- Snowy Plovers than between Kentish and White- typic, including subspecies phaeopus, alboaxil- fronted Plovers Charadrius marginatus. Finally, laris and variegatus) male courtship calls of Kentish and Snowy Plovers Other subspecies of both Eurasian and Hudso- may also differ (Küpper et al. 2009). nian Whimbrel have been proposed by Engelmoer The plumage characters and nomenclature of the and Roselaar (1998) and Tomkovich (2008) which East Asian White-faced Plover Charadrius alexan- may deserve recognition. Eurasian Whimbrel and drinus dealbatus have recently been clarified (Bake- Hudsonian Whimbrel are both in Category A of well & Kennerley 2008, Kennerley et al. 2008). the British List. White-faced Plover is retained here as a subspecies of Kentish Plovers pending ongoing studies. Great Skua Stercorarius skua Kentish Plover is best treated as two species: • Kentish Plover Charadrius alexandrinus (poly- Relationships of Stercorarius skua are uncertain. typic, with subspecies alexandrinus, seebohmi, Mitochondrial DNA analyses have suggested that nihonensis and dealbatus) S. skua is more closely related to Stercorarius • Snowy Plover Charadrius nivosus (polytypic, pomarinus than to taxa breeding in the southern see Funk et al. 2007) hemisphere (Blechschmidt et al. 1993, Cohen Kentish Plover is in Category A of the British et al. 1997, Ritz et al. 2008, but see Braun & List. Brumfield 1998), whereas analyses of morphology and ectoparasites support monophyly of the ‘great skuas’ (Andersson 1999a, 1999b, Chu et al. 2009). Whimbrel Numenius phaeopus As well as genetic differences from southern Hudsonian Whimbrel Numenius phaeopus hudsoni- hemisphere skuas, Great Skua differs from all cus is separable from Eurasian Whimbrel Numenius other skuas in plumage at most ages (Furness phaeopus phaeopus on the basis of diagnostic differ- 1987, Malling-Olsen & Larsson 1997). Among the ences in plumage and mean morphometric differ- southern skuas, Chilean Skua Stercorarius skua chil- ences (Hayman et al. 1986, Engelmoer & Roselaar ensis and South Polar Skua Stercorarius skua mac- 1998). Hudsonian Whimbrel shows marked diver- cormicki are well differentiated on the basis of gence in mitochondrial DNA sequences (around morphology from Brown Skua taxa, Stercorarius 3.6% sequence divergence in the CO1 gene) from skua antarcticus, Stercorarius skua hamiltoni and ª 2011 The Authors Ibis ª 2011 British Ornithologists’ Union Taxonomic recommendations for British birds: seventh report 885 Figure 1. Phylogenetic relationships among Whimbrels Numenius phaeopus and other curlews based on maximum likelihood (ML) analysis of 694 bp of cytochrome c oxidase sub-unit 1, using Bartramia longicauda as outgroup. The best-fit model was estimated with MEGA5 (Tamura et al. 2011) based on the corrected Akaike information criterion. The selected model was HKY + G. To further evalu- ate statistical support for the topology, maximum parsimony (MP) bootstrapping was performed in MEGA5 and Bayesian analysis was performed using MRBAYES version 3.1.2 (Ronquist & Huelsenbeck 2003). Default priors in MRBAYES were used. Four Metropolis-coupled MCMC chains with incremental heating temperature 0.2 were run for 300 000 generations, and sampled every 100 generations. The first 750 trees were discarded as burn-in and the posterior probability estimated for the remaining sampled generations. Numbers above branches indicate Bayesian posterior probabilities; numbers below represent bootstrap support (1000 replicates) from MP and ML analyses, respectively. GenBank accession numbers and, for Whimbrels, collecting localities are given. Stercorarius skua lonnbergi (Furness 1987, see also Skuas and differences in arrival time between spe- Hospitaleche et al. 2009). Chilean, Brown and cies and sexes in the contact zone (Parmalee 1988, South Polar Skuas are also significantly differenti- Hahn et al. 2003, Ritz et al. 2006). Mating pat- ated from each other in mitochondrial control terns in a mixed colony of King George Island indi- region sequences (Ritz et al. 2008). In addition, cate that heterospecific pairs are