The two main populations of Parabuteo unicinctus have long been treated as subspecies of the same species: Harris's Hawk P. u. harrisi in the southern USA to Costa Rica, and Bay-winged Hawk P. u. unicinctus in South America. However, they differ considerably in their morphology, number of plumages, and behavioural ecology. Adult Harris's Hawk differs in multiple plumage characters from adult Bay-winged Hawk, and differences are even more marked in juvenile plumage. Harris's Hawk has two age-related plumages but Bay-winged Hawk shows delayed plumage maturation and has four such plumages. Harris's Hawk breeds and hunts cooperatively, whereas Bay-winged Hawk nests only in pairs, and hunts individually. There are no valid records of Harris's Hawk in South America. We believe that the differences in adult and juvenile plumages, the number of immature plumages, and differences in breeding and hunting mean that Harris's Hawk and Bay-winged Hawk are best treated as separate species.

In 2008 the International Commission for Zoological Nomenclature (ICZN) ruled that the name Streptopelia risoria (Linnaeus, 1758) should have priority for both African Collared Dove and its domestic form, Barbary Dove, as it is senior to S. roseogrisea (Sundevall, 1857). Many ignored the ruling in the belief that the ancestry of Barbary Dove is still unproven. Given the lack of a name-bearing specimen and in anticipation of the ICZN decision, in 2008 a neotype was designated for S. risoria. To clarify the taxonomic status of roseogrisea, as its original type series was mixed, in 2018 a neotype was also designated for this junior synonym of African Collared Dove. As the species was assumed to be polytypic, synonymisation of roseogrisea with risoria at species level was questioned thereafter. The results of a whole genome-resequencing study now show that African Collared Dove is the principal ancestor of Barbary Dove, and that the species is monotypic.

Based on 30 days of field surveys in the north-west of the state of Minas Gerais, Brazil, in 2014, I report notable records of 40 bird species. In total, 293 species were recorded at three sites, including 15 species at risk of extinction (at state, national or global levels) and another four species whose status is insufficiently known to be placed in any threat of extinction category in Minas Gerais or Brazil. Records of three species are new for the São Francisco basin, and 13 are new for north-west Minas Gerais. Among the rarest species reported are Dwarf Tinamou Taoniscus nanus, Jabiru Jabiru mycteria, Black Hawk-Eagle Spizaetus tyrannus, Ocellated Crake Micropygia schomburgkii, Uniform Crake Amaurolimnas concolor, Russet-mantled Foliage-gleaner Syndactyla dimidiata, Minas Gerais Tyrannulet Phylloscartes roquettei, Chapada Flycatcher Guyramemua affine, Reiser's Tyrannulet Phyllomyias reiseri, Rufous-tailed Attila Attila phoenicurus, Black-collared Swallow Pygochelidon melanoleuca and Blackish-blue Seedeater Amaurospiza moesta.

I reviewed the material basis of Muscicapa virens Linnaeus, 1766, long presumed to be the original description of Eastern Wood Pewee Contopus virens (Linnaeus), type species of the genus Contopus Cabanis, 1855, and found it to be an unidentifiable taxonomic composite. Linnaeus' (1766) account was partly based on Brisson's (1760) ‘Gobe-mouche Cendré de la Caroline’, which was based on (1) a non-extant specimen that, as demonstrated herein, was probably a species in the genus Empidonax Cabanis, 1855, and (2) Catesby’s (1731) ‘little brown Fly-catcher’, which was also a taxonomic composite. Linnaeus (1766) also included a novel character in his original description of M. virens—a white supercilium (‘superciliis albis’)—which is lacking in Eastern Wood Pewee, and was probably miscopied from Catesby’s (1731) description of ‘Red-eyed Fly-catcher’ (= Red-eyed Vireo Vireo olivaceus Linnaeus, 1766), which appeared on the same plate as the ‘little brown Fly-catcher’. In light of these ambiguities, after a thorough review of literature and relevant primary sources, I designate a neotype specimen for C. virens (Linnaeus) that stabilises nomenclature in accordance with prevailing use.

I discuss why the tropical island of New Guinea has long been important in the development of our understanding of birds. There are two sets of reasons: New Guinea's birds, and its geography and peoples. New Guinea birds include: the famous birds of paradise, bowerbirds, and megapodes, which evolved in New Guinea (or New Guinea plus Australia) and are still concentrated there; pigeons, parrots, and kingfishers, which are especially species-rich and diverse in New Guinea and radiated there, whether or not they originally evolved there; and many groups that are morphologically and ecologically similar to European groups, such as ‘wrens’, ‘creepers’, and ‘nuthatches’, but that proved to be ‘lookalikes’ that evolved independently in New Guinea / Australia, just as numerous marsupial mammals and placental mammals converged on similar morphologies. Finally, the poisonous pitohuis and ifrit independently acquired the same neurotoxin as did South American poison-dart frogs; and a melampitta roosts and nests underground. The advantages offered by the island itself include: its equatorial location and its high mountains, so that New Guinea offers the entire range of habitats from coral reefs and rainforests through alpine grassland and glaciers on one short transect; the ‘right size’ (sufficient species to illuminate but not too many species so as to confuse); a simple geographic layout comprising a central mountain chain and its lowland ring; hundreds of islands of three types; virtually complete knowledge of the composition of its resident avifauna at the level of species; and the encyclopedic knowledge of birds among traditional New Guinea peoples. As examples of phenomena of general biological interest that New Guinea birds have illuminated, I discuss elevational sequences of congeners, culture in bowerbirds, evolution of ‘aggressive mimicry’ of larger bird species by smaller birds, brown-and-black mixed-species foraging flocks, and selection for and against overwater dispersal. These birds, landscapes, and topics are illustrated by photographs by K. David Bishop.

Ruby-throated Bulbul Rubigula dispar, currently Vulnerable on the IUCN Red List owing to trade pressure, is considered monotypic across its range on three Sundaic islands in Indonesia: Sumatra, Java and Bali. However, examination of photographs and museum specimen labels and measurement of 37 Sumatran and 50 Javan specimens indicate that birds from Sumatra differ from those on Java (type locality) and Bali in exhibiting a variably red (not pale yellow) iris and a slightly longer bill and wing. Consequently, we propose subspecies rank for the Sumatran population. We recommend that the two taxa be maintained pure in captivity and that any releases of confiscated birds take place on the correct island based on eye colour.

In a recent article (Bull. Brit. Orn. Cl. 142: 329–342), Matthew Halley contended that John James Audubon (1785–1851) lied about his discovery of Lincoln's Sparrow Melospiza lincolnii (Audubon, 1834) during his 1833 Labrador expedition. Extracts from the naturalist's journal, published after his death in a biography prepared by his widow, Lucy (1787–1874), states that he was aboard ship ‘Drawing all day’ when the specimen was collected by one of his assistants. Consequently, Halley submitted that Audubon’s claim in the Ornithological biography to having first sighted the bird was fabricated and that his granddaughter Maria R. Audubon (1843–1925) doctored her alternate version of the journal to be consistent before she destroyed the original. However, Halley overlooked critical facts, including evidence that Lucy’s manuscript was compiled and edited by others; the published work contained numerous errors; and the journal entries for the previous two weeks were misdated and sometimes conjoined from multiple days, proving that her journal was not a faithful transcription of the original.

The name Struthio australis Gurney Sr, 1868, was based on three captive birds that arrived at the Zoological Society of London in November 1861. A skeleton of one of these is shown to survive in the bird collection of the Natural History Museum, but whether the other two syntypes still exist is doubtful.

An adult thrush trapped in a mist-net near Guayaramerin, dpto. Beni, Bolivia, in April 2005, was initially identified as Black-billed Thrush Turdus ignobilis although several subtle plumage features appeared to differ from the expected race T. i. debilis. These features match those of Campina Thrush T. arthuri, a cryptic species subsequently split from Black-billed Thrush based on molecular evidence, and now known to occur widely in shrubby thickets and stunted campina forest across much of Amazonia. This record extends the known distribution of T. arthuri south-west from the nearest known localities in Amazonas and Rondônia, Brazil. T. arthuri is presumably resident in north-west dpto. Beni in suitable habitat, and potentially occurs elsewhere in Bolivia from Pando to eastern Santa Cruz in similar campina-like habitats associated with weathered outcrops of the Brazilian Shield.

A total of 20 individual Phylloscopus warblers in the ‘Blyth’s Leaf Warbler P. reguloides lineage’, caught for ringing in the non-breeding season in Thailand and Myanmar, were resolved via mtDNA assay as P. reguloides (seven individuals), Claudia’s Leaf Warbler P. claudiae (12) and Hartert’s Leaf Warbler P. goodsoni (one). As expected, P. claudiae proved to be the most widely distributed. The occurrence of four P. claudiae on an island in the Thai Gulf, alongside large numbers of typically Sundaic wintering species on northbound migration during late March–early April, indicates that its non-breeding season range probably extends further south than previously recognised, into that subregion.