The Arabian Bustard Ardeotis arabs occupies open arid country from West (and formerly north-west) Africa to coastlands either side of the Red Sea. Five subspecies have been described, nominate arabs in south-west Arabia and northeast Africa, stieberi from the Red Sea to the Atlantic Ocean, butleri in South Sudan and Kenya, geyri in north-west Niger, and the extinct lynesi in Morocco. All taxa were described on the basis of the shade of upperpart coloration, with lynesi and butleri equally dark, and arabs, stieberi and geyri each successively paler. Of these, geyri alone has been widely discounted as invalid, for reasons of diagnosability and possible clinality which, however, could equally well apply to the other taxa. Indeed, ten informal commentaries on the variation found in the species, taken together, imply significant scepticism over the value of dividing it into subspecies. Examination of museum specimens and photographs of wild birds justifies that scepticism, with the holotype of geyri proving darker than a specimen of stieberi, a proportion of stieberi darker than nominate arabs, a specimen of the former as dark as a pale lynesi, and a living butleri as pale as nominate arabs and some stieberi; no strong differences in size between taxa, including the seemingly slightly smaller lynesi, are apparent. This evidence confounds the diagnosability of any subspecies and suggests the observed variation may simply reflect the influence of Gloger's Rule or else substrate matching. A better option is to treat the species as monotypic.
During ongoing research, initiated by JM, in the Natural History Museum, Tring, bird collections, four cases have been identified where it is necessary to objectively define the relevant taxa; two by lectotypification and two by neotypification. The first of these is Western Tragopan Tragopan melanocephalus (J. E. Gray, 1829), of which the male and female syntypes are identifiable as different species, with the female being a juvenile male Satyr Tragopan T. satyra (Linnaeus, 1758). The second involves Dicrurus cathoecus Swinhoe, 1871, currently treated as a subspecies of Black Drongo D. macrocercus (Vieillot, 1817) and which was described from specimens collected in mainland China, the islands of Hainan and Taiwan. Subsequently, Dicrurus ater harterti E. C. S Baker, 1918, now also a subspecies of D. macrocerus, was named on the basis of a specimen collected on Taiwan, but without unambiguously excluding Swinhoe's nomen from Taiwan. The final case pertains to Dicrurus macrocercus Vieillot, 1817, and its objective synonym D. indicus Stephens, 1826, which were based on Levaillant's (1805: pl. 174) ‘le Drongolon’, supposedly from South Africa. Since the mid-19th century, authors have invariably applied the name D. macrocercus to the birds of ‘India’ sensu lato, but to which taxon within the macrocercus complex this name applies there is no consensus. To our knowledge, the type material of Levaillant’s ‘le Drongolon’ no longer exists, and therefore there are also no extant types of Vieillot’s and Stephens’ nominal species. As a result, lectotype designations are offered for the first two above cases, and the same neotype designation for Dicrurus macrocercus Vieillot, 1817, and D. indicus Stephens, 1826, in order to fix the identities on the universally understood taxonomic concept associated with each of these taxa.
Extinct and endangered (E&E) specimens are among the most valued in natural history collections and are often subject to heightened curatorial care. Based on data published in 2000 by BirdLife International as part of its assessment of species against the IUCN Red List criteria, Adams et al. (2003) established an E&E list of 481 bird species for use by museum collection managers. However, given the dynamic nature of extinction risk and improved knowledge of many threatened taxa over the past 23 years, several aspects of this list are now outdated. Using criteria similar to those developed by Adams et al. (2003), we provide an updated E&E list comprising 626 species (of which 164 are listed on the IUCN Red List as Extinct). The increase in the number of species admitted by 29% is attributable chiefly to four factors: (1) genuine changes in species' extinction risk; (2) corrections to the data underpinning Red List assessments; (3) changes in taxonomy; and (4) the novel inclusion of species listed as Data Deficient. Our list provides a suggested update for E&E inventories but may be adapted by museums and others to ensure the protection of other ornithological material considered of heightened value or scarcity.
Sabine's Gull Xema sabini was first recorded off South Africa in 1957. The numbers of this species migrating to the southern Benguela Upwelling System subsequently increased steadily so that, by the 1980s, flocks numbering in the thousands were observed regularly in Table Bay, South Africa. This population has since declined, however, to the extent that the species was observed only singly or in small flocks in the early 2020s.
The East Andes of Colombia is a biogeographically complex region with significant avian diversity and endemism. Despite previous efforts, large portions of its northern sector remain unexplored ornithologically. We report new distributional data for 38 bird species at 42 localities in Santander and Norte de Santander departments, spanning elevations from 825 m to 3,700 m. These records bridge notable distributional gaps for several Andean species and expand known ranges northward, particularly in montane forest ecosystems. Among others, we report range extensions for Solitary Eagle Buteogallus solitarius, Chapman's Swift Chaetura chapmani, Cinnamon Screech Owl Megascops petersoni, Yellow-throated Spadebill Platyrinchus flavigularis and Sooty Grassquit Asemospiza fuliginosa, as well as the first specimen records for Colombia of Streak-capped Treehunter Thripadectes virgaticeps tachirensis and Russet Antshrike Thamnistes anabatinus gularis. The results underscore the role of geographic barriers, such as arid river canyons and high elevations in shaping avian distributions, leading to disjunct populations and potential zones of secondary contact. Our study emphasises the value of combining historical data, modern observations and specimen collection to clarify species distributions, taxonomy and evolutionary patterns. It also stresses the need for rigorous field documentation, including detailed locality descriptions and habitat notes, to improve data quality and their long-term utility. Continued exploration of understudied areas, such as the east slope of the Sierra Nevada del Cocuy and fragmented foothill forests, is essential to uncover additional biodiversity and to inform conservation efforts.
