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Breeding phenology and moult of the endemic Bannerman's Weaver Ploceus bannermani
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Yahkat Barshep --- AP Leventis Ornithological Research Institute, Nigeria Shiiwua A Manu --- AP Leventis Ornithological Research Institute, NigeriaThe breeding phenology and moult cycle of the vulnerable and range-restricted Bannerman's Weaver Ploceus bannermani was studied on the Obudu Plateau in the eastern region of Nigeria. The peak breeding season was between August and October; a major cause of... -
Collapse of South Africa's penguins in the early 21st century
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: RJM Crawford --- Oceans and Coasts, Department of Environmental Affairs, South Africa R Altwegg --- Animal Demography Unit, South Africa BJ Barham --- , UK PJ Barham --- Animal Demography Unit, South Africa JM Durant --- Centre for Ecological and Evolutionary Synthesis (CEES), Department of Biology, Norway BM Dyer --- Oceans and Coasts, Department of Environmental Affairs, South Africa D Geldenhuys --- , South Africa AB Makhado --- Oceans and Coasts, Department of Environmental Affairs, South Africa L Pichegru --- Percy FitzPatrick Institute of African Ornithology, South Africa PG Ryan --- Percy FitzPatrick Institute of African Ornithology, South Africa LG Underhill --- Animal Demography Unit, South Africa L Upfold --- Oceans and Coasts, Department of Environmental Affairs, South Africa J Visagie --- , South Africa LJ Waller --- Animal Demography Unit, South Africa PA Whittington --- , South AfricaThe number of African penguins Spheniscus demersus breeding in South Africa collapsed from about 56 000 pairs in 2001 to some 21 000 pairs in 2009, a loss of 35 000 pairs (>60%) in eight years. This reduced the global... -
Comparison of moult phenology of African penguins Spheniscus demersus at Robben and Dassen islands
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: AC Wolfaardt LG Underhill RJM CrawfordDassen and Robben islands are approximately 50 km apart, and currently support the largest and third largest populations of African penguins Spheniscus demersus respectively. At both islands, moult is the most synchronised and seasonal activity of the annual cycle. The... -
Breeding and moult phenology of African penguins Spheniscus demersus at Dassen Island
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: AC Wolfaardt --- , South Africa LG Underhill --- Animal Demography Unit, Department of Zoology, South Africa J Visagie --- , South AfricaThe breeding and moult phenology of African penguins Spheniscus demersus at Dassen Island form part of a variable annual cycle. Between 1994 and 2006, African penguins bred throughout the year. Most of this period was characterised by favourable feeding conditions... -
Primary wing-moult and site fidelity in South African mousebirds (Coliidae)
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Adrian JFK Craig --- Department of Zoology and Entomology, South Africa Bo T Bonnevie --- Information Technology Division, South Africa Patrick E Hulley --- Department of Zoology and Entomology, South Africa George D Underhill --- ,Based on large samples of birds mist-netted in the Eastern Cape and the Western Cape, moult of the primary remiges in both Speckled Mousebirds Colius striatus and Red-faced Mousebirds Urocolius indicus occurred throughout the year with no regional or seasonal... -
The timing of moult in males and females of the monomorphic Pale-winged Starling Onychognathus nabouroup
Item type: Journal Article • Journal: African Zoology • Authors: Adrian JFK Craig --- Department of Zoology and Entomology, Rhodes University, South Africa Martine Hausberger --- UMR CNRS 6552 Ethologie animale et humaine, Université de Rennes-1, France Bo Bonnevie --- Information Technology Division, Rhodes University, South Africa Laurence Henry --- UMR CNRS 6552 Ethologie animale et humaine, Université de Rennes-1, FrancePale-winged Starlings Onychognathus nabouroup inhabit the arid western interior of southern Africa and moult– breeding overlap may occur. We collected field data in two successive years on the moult of individual birds, whose sex was confirmed by genetic techniques. Small... -
Moult in the Mediterranean monk seal from Cap Blanc, western Sahara
Item type: Journal Article • Journal: African Zoology • Authors: Enric Badosa --- Departament de Biologia Animal, Spain Teresa Pastor --- Departament de Biologia Animal, Spain Manel Gazo --- Departament de Biologia Animal, Spain Alex Aguilar --- Departament de Biologia Animal, SpainAt birth, the Mediterranean monk seal (Monachus monachus) is covered with dark lanugo This is shed earlier and faster in females, so they complete the moult when they are significantly younger (64 days) than males (82 days). Moulted pups present... -
Ecology and behaviour of Palm-nut Vultures Gypohierax angolensis in the Bijagós Archipelago, Guinea-Bissau
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Camilo Carneiro --- Department of Biology and CESAM, Portugal Mohamed Henriques --- Faculty of Sciences, Portugal Castro Barbosa --- Institute of Biodiversity and Protected Areas of Guinea-Bissau, Guinea-Bissau Quintino Tchantchalam --- Institute of Biodiversity and Protected Areas of Guinea-Bissau, Guinea-Bissau Aissa Regalla --- Institute of Biodiversity and Protected Areas of Guinea-Bissau, Guinea-Bissau Ana R Patrício --- Centre for Ecology and Conservation, UK Paulo Catry --- MARE – Marine and Environmental Sciences Centre, PortugalPopulations of many vulture species have undergone substantial declines. In Africa, 82% are threatened and although research on vultures has increased, the biology and ecology of several species is still poorly known. The Palm-nut Vulture Gypohierax angolensis has peculiar ecological... -
The simultaneous moult of female hornbills is not triggered by the darkness of their nest cavity
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Mark Stanback --- Department of Biology, Davidson College, USA David Millican --- Department of Biological Sciences, USA Paul Visser --- Cheetah Conservation Fund, Namibia Laurie Marker --- Cheetah Conservation Fund, NamibiaA verbal model from 1937 proposed that the darkness of the nest cavity acts as a proximate trigger for the simultaneous moult observed in female hornbills. Although never tested, the plausibility of this hypothesis has allowed it to be cited... -
Plumage development and moult in captive Black-bellied Sandgrouse Pterocles orientalis: age and sex variations
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Mohamed Aourir --- Department of Biology, Faculty of Sciences, Morocco Mohammed Znari --- Department of Biology, Laboratory «Biodiversity and Ecosystem Dynamics», Faculty of Sciences – Semlalia, Morocco Mohamed Radi --- Department of Biology, Laboratory «Biodiversity and Ecosystem Dynamics», Faculty of Sciences – Semlalia, MoroccoThe sandgrouse, family Pteroclididae, are a group of birds adapted to open, arid habitats and powerful fliers but information on their plumage development and moult is scarce. In this study, the annual cycle of body plumage development, sequence and duration... -
Timing, duration and symmetry of moult in Cape Gannets
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Oluwadunsin E Adekola --- , South Africa Robert JM Crawford --- , South Africa Bruce M Dyer --- , South Africa Azwianewi B Makhado --- , South Africa Leshia Upfold --- , South Africa Peter G Ryan --- , South AfricaLittle has been reported on moult in sulids, including gannets. The Cape Gannet Morus capensis is an endangered seabird endemic to southern Africa. We describe the timing, duration, symmetry and sequence of flight feather moult in Cape Gannets from two... -
Wing-moult and seasonal occurrence of sunbirds (Nectariniidae) captured at four sites in the Eastern Cape, South Africa
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Bo T Bonnevie --- Rhodes University, South Africa Adrian JFK Craig --- Rhodes University, South Africa Pat E Hulley --- Rhodes University, South Africa Albert Schultz --- , South Africa Anthony J Tree --- Rhodes University, South AfricaRinging activity in the Eastern Cape province, South Africa, spanned 30 years, with three sites active concurrently over a 14-year period, and three sites over a 6-year period. In total, in the course of 714 ringing days, in all months,... -
Plumage dimorphism and moult patterns of weaverbirds – a review
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: H-Dieter Oschadleus --- University of KwaZulu-Natal, South Africa Staffan Andersson --- University of Gothenburg, SwedenThe colourful plumages of weaverbirds (family Ploceidae, with 118 species recognised) provide a well-known and in part iconic showcase of sexual selection, with widespread sexual dimorphism (93 species) as well as seasonal dimorphism (62 species). The tremendous diversity in both... -
A demonstration of the value of recapture data for informing moult phenology models for avian species with imperfect moult data
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Philipp H Boersch-Supan --- , United Kingdom Alan Tristram Kenneth Lee --- University of Cape Town, South Africa Hans-Dieter Oschadleus --- University of KwaZulu-Natal, South AfricaThe Underhill–Zucchini model has revolutionised the study of moult in the context of birds’ annual cycles, but, as for all statistical models, inferences are vulnerable to violations of model assumptions. In particular, the standard Underhill–Zucchini models for moult phenology are... -
Primary moult in the annual cycle of adult African Oystercatchers Haematopus moquini
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Taylyn C Bate --- University of Cape Town, South Africa Peter G Ryan --- University of Cape Town, South Africa Les G Underhill --- University of Cape Town, South AfricaAfrican Oystercatchers Haematopus moquini are sedentary, intertidal foraging birds, range-restricted to Namibia and South Africa. Their annual cycle has two components: breeding and moult. The Underhill–Zucchini model estimated a primary moult duration of 154 days, and mean start and completion... -
Primary moult of adult Laughing Doves Spilopelia senegalensis: introduction of the relative duration index and a comparison of moult indices
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Tanya Scott --- University of Cape Town, South Africa Les G Underhill --- University of Cape Town, South Africa George D Underhill --- University of Cape Town, South AfricaA new moult index, the relative duration index (RDI), was developed to quantify progress through moult using the Underhill–Zucchini model of primary avian moult, with the Laughing Dove Spilopelia senegalensis as a case study. The RDI weights individual primaries in... -
Pattern and intensity of moult in White-capped/Shy Albatrosses Thalassarche steadi/cauta
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Peter G Ryan --- University of Cape Town, South Africa Oluwadunsin E Adekola --- University of Cape Town, South AfricaAlbatrosses typically only replace a subset of flight feathers each annual moult cycle. We scored the moult of 662 White-capped/Shy Albatrosses Thalassarche steadi/cauta, using birds that had been killed by longline fisheries off South Africa. Most adults and immatures alternated... -
The primary moult of adult Red-headed Finches Amadina erythrocephala
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: T Scott --- University of Cape Town, South Africa JMH Raijmakers --- , South Africa LG Underhill --- University of Cape Town, South AfricaLittle is known about the biology of the Red-headed Finch Amadina erythrocephala. This study investigates its primary moult, the first aspect of its life history to be looked at in depth. Additionally, we used a modified Cook’s distance algorithm to... -
Multiple circannual moult strategies: feather tract moult patterns for common birds of the central Fynbos region, South Africa
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Alan TK Lee --- University of KwaZulu-Natal, South AfricaWhen and where birds lose their feathers during the annual moult cycle is a fascinating subject, but there is little reported on patterns and strategies of moult for most African bird species. While there have been great advances in our... -
Influence of groups of points on estimates of the parameters of moult
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Les G Underhill --- University of Cape Town, South Africa Tanya Scott --- University of Cape Town, South AfricaThe Underhill–Zucchini model of avian moult is a statistical simplification for the analysis of primary moult, a complex biological system in birds. As with all such models, conclusions can be biased if a subset of the data used to fit...