Geokichla ground thrushes (Turdidae) are widely distributed, in Siberia, South-East Asia, Indonesia, the Indian Subcontinent, Nicobar and Andaman Islands, and continental Africa. Based on recently discovered subfossil remains, I describe a Geokichla from Mauritius, a new genus for the Mascarene Islands, which presumably became extinct historically, although it seems never to have been reported in the literature. The new species appears closely related to the extant Orange-headed Thrush G. citrina of South-East Asia, so probably island-hopped via the Nicobar or Andaman Islands to Mauritius during low sea level stands, as did some other Mauritian endemic birds. Like Geokichla in general, the Mauritius species probably inhabited the understorey or forest floor, and as a result disappeared due to the introduction of invasive species, especially rats, by humans.

I present new information on the breeding biology of six bird species found in the Ecuadorian Amazon. I describe, for the first time, the nests of Oleaginous Hemispingus Sphenopsis frontalis and Black-eared Hemispingus S. melanotis, as well as providing the first descriptions of the eggs of Black-eared Hemispingus, Streak-headed Antbird Drymophila striaticeps, Mottle-backed Elaenia Elaenia gigas and Casqued Cacique Cacicus oseryi. I also provide the first detailed nest description for Black-banded Crake Anurolimnas fasciatus, and correct previous descriptions of its eggs.

This is the first in a planned series of articles about the breeding behaviour of Brazilian birds. Field work has been carried out in various regions of Brazil since the 1980s. The descriptions cover various aspects of reproductive biology, such as seasonality, nest architecture, materials and measurements, clutch size, egg colour, size and shape, incubation period, nestling period, and parental care. Many data are presented scientifically for the first time. In this first paper, we present data for 16 species: Greater Rhea Rhea americana (two nests, including the first information from north-east Brazil), Small-billed Tinamou Crypturellus parvirostris (20 nests), Red-winged Tinamou Rhynchotus rufescens (three nests), Spotted Nothura Nothura maculosa (11 nests), Horned Screamer Anhima cornuta (four nests, possibly with the first biometrics of eggs in the wild from Brazil), Southern Screamer Chauna torquata (five nests), White-faced Whistling Duck Dendrocygna viduata (three nests), Black-bellied Whistling Duck D. autumnalis (eight nests), Muscovy Duck Cairina moschata (two nests), Brazilian Teal Amazonetta brasiliensis (one nest), White-cheeked Pintail Anas bahamensis (one nest), Rusty-margined Guan Penelope superciliaris (seven nests, probably with the first data on reproductive success), Chaco Chachalaca Ortalis canicollis (one nest), East Brazilian Chachalaca O. araucuan (one nest), Least Grebe Tachybaptus dominicus (six nests) and Pied-billed Grebe Podilymbus podiceps (one nest).

Black Redstart Phoenicurus ochruros occurs over a broad range from Western Europe and north-west Africa to Central Asia. Seven subspecies are usually recognised, which can be divided morphologically into a grey-and-white-bellied western group (‘Western Black Redstart’; two subspecies) and an orange-bellied eastern group (‘Eastern Black Redstart’; five subspecies). Because vocalisations might help to understand relationships between these taxa, we analysed the calls of six of the seven subspecies. We demonstrate that calls can be grouped into one of three geographical variants. One is formed by the western subspecies breeding in Europe, the morphologically intermediate subspecies ochruros and Eastern Black Redstarts from the Altai and Mongolia. Further south-east, birds call at lower frequencies on average and within a smaller frequency range (group 2). The third group is formed by the eastern subspecies rufiventris which differs from all other taxa, with a descending instead of a rising call, given at much lower frequencies.

A review of eight molecular phylogenetic studies supports the distinctiveness of the genera Sasia/Verreauxia from Picumnus and casts doubt on the monophyly of Picumninae. We propose to restrict Picumninae to Picumnus and to place Sasia and Verreauxia in a new subfamily, Sasiinae.

Slender-billed Curlew Numenius tenuirostris is Critically Endangered and may be extinct. Its breeding biology is known exclusively from early 20th-century accounts from central Russia and Kazakhstan, and the eggs were heretofore known from a single specimen in the Manchester Museum. Here, we provide details of five additional putative Slender-billed Curlew eggs held in public and private collections. The eggs show remarkable variation in size, with two being only 85% of the mean length and breadth. Notably, one of the putative clutches was from the European side of the Ural Mountains, far to the west of the established breeding range. Molecular identification would aid in identifying additional specimens, which would be easily confused with eggs of other Numenius.

The first records of Swallow Tanager Tersina viridis in Uruguay were made in 2012 and 2022 in different regions of the country. Together with other observations in central-south South America outside its usual distribution, these data appear to support the hypothesis that the species makes erratic movements in search of food during the austral winter non-breeding period. Alternatively, the new records could reflect an expansion of the species' distribution.

We present an addendum to the list of known specimens of Imperial Woodpecker Campephilus imperialis published by Brown & Clark in 2009. The addendum adds a total of 31 specimens, comprising 15 mounts, ten study skins, three skeletons, two skulls and one not extant specimen, bringing the total number to 189 specimens. It also offers clarification of some of the records presented in Brown & Clark, as well as revisions of several specimens previously registered as C. imperialis but later found to be of other species. The latter includes a putative clutch of Imperial Woodpecker eggs, which was found via genetic analysis to belong to Burrowing Owl Athene cunicularia.

Distributed in four areas of Africa (‘Eastern’—east of the Gregory Rift Valley from central Kenya south to Malawi; ‘Central’—west of the Gregory Rift from western Kenya and western Uganda south to Burundi and eastern Democratic Republic of Congo; ‘Western’—Nigeria and Cameroon plus Bioko; and Angola), Bar-tailed Trogon Apaloderma vittatum is at present widely judged to be monotypic. However, photographic evidence reveals three different facial patterns in these populations, with a bare ear spot and whitish-green bill in Eastern and Angolan birds, a bare ear spot, golden-yellow bill and bare gape line in Central birds, and these same features plus a distinct bare crescent above the eye in Western birds. Central and Western birds also have broader, more distinct barring on the wing panel. Moreover, there is a stepped cline in sizes in these three distinct populations, from Eastern plus Angola (largest) through Central to Western (smallest), with Bioko birds having notably short tails; and songs also decelerate from east to west, but with too much overlap to be diagnosable. Nevertheless, under the Tobias criteria the morphological differences of Central and Western birds vs. Eastern and Angolan populations accord the former species rank, for which the name camerunense is available. This latter species itself breaks into three subspecies, with the nominate in Nigeria and Cameroon, francisci on Bioko, and a new name for the hitherto taxonomically unrecognised Central populations.

We report the first record of Lesson's Seedeater Sporophila bouvronides, a South American species, in Costa Rica. It was seen at Tortuguero, in the lowlands of north-east Costa Rica in June 2022. The record is perhaps explained by the passage of a tropical storm that moved north-west from off northern South America.