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A review of Jouanin's Petrel records in the eastern Indian Ocean
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: PeterG Ryan --- DST/NRF Centre of Excellence at the Percy FitzPatrick Institute, South Africa Barrie Rose --- , South Africa Michael Carter --- , Australia RohanH Clarke --- School of Biological Sciences, AustraliaJouanin's Petrel Bulweria fallax mainly occurs in the western Indian Ocean. Prior to our study there were only two records from east of 82° E. We show that small numbers of Jouanin's Petrels are regular visitors to the eastern Indian... -
Living on the bare edge: fitness consequences for Cape Gannets Morus capensis at Bird Island, Algoa Bay
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: David Green --- DST/NRF Centre of Excellence at the Percy FitzPatrick Institute, Department of Zoology, South Africa Pierre Pistorius --- DST/NRF Centre of Excellence at the Percy FitzPatrick Institute, Department of Zoology, South AfricaAvian breeding colonies often suffer high levels of predation along their margins. Nest predation is a major fitness concern for parents and therefore nests inside of the colony edge might be at a premium. This was tested through studying the... -
Conserving Surface-nesting Seabirds at the Prince Edward Islands: The Roles of Research, Monitoring and Legislation
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: R. J. M. Crawford J. CooperSouth Africa's subantarctic Prince Edward Islands support substantial proportions of the global populations of a number of surface-nesting seabirds. Populations of most of these have decreased at the islands since the 1980s and 12 of 16 species are regarded as... -
Counts of Surface-nesting Seabirds Breeding at Prince Edward Island, Summer 2001/02
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: P. G. Ryan J. Cooper B. M. Dyer L. G. Underhill R. J. M. Crawford M. N. BesterThe first midsummer survey of surface-nesting seabirds at Prince Edward Island was conducted during December 2001. It was also the first census for most species since the early 1980s. Despite concerns about the impacts of longline fishing mortality on various... -
Accounting for food requirements of seabirds in fisheries management – the case of the South African purse-seine fishery
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: R. J. M. CrawfordIn South Africa, four of the seabirds that feed mainly on sardine Sardinops sagax and anchovy Engraulis encrasicolus have an unfavourable conservation status or a small population: African penguin Spheniscus demersus, Cape gannet Morus capensis, Cape cormorant Phalacrocorax capensis and... -
Wintering seabirds in West Africa: foraging hotspots off Western Sahara and Mauritania driven by upwelling and fisheries
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: CJ Camphuysen J van der MeerCold-water upwelling supports abundant and diverse faunas. Upwelling off Mauritania has been highlighted as being important for seabirds, but very few systematic offshore surveys have been conducted in that region. Mauritanian waters are increasingly targeted by commercial fisheries along the... -
Seabirds in the diet of Cape fur seals Arctocephalus pusillus pusillus at three mainland breeding colonies in Namibia
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: S Mecenero SP Kirkman J-P RouxPredation by Cape fur seals Arctocephalus pusillus pusillus on seabirds has previously been attributed to a few individuals, mainly males. Scat samples were collected at three mainland breeding colonies of seals in Namibia to determine the extent of seabird predation... -
Birds and conservation significance of the Namib Desert's least known coastal wetlands: Baia and Ilha dos Tigres, Angola
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: RE Simmons A Sakko J Paterson A NzuziThe Ilha dos Tigres of Angola is the only sandy island off the coast of the 2 000km-long Namib Desert and it remains the least known coastal wetland on a desert coast rich in shorebirds. Two surveys of the Baia... -
St Helena Bay (southern Benguela) then and now: muted climate signals, large human impact
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: L Hutchings --- Department of Environmental Affairs, South Africa A Jarre --- Marine Research (MA-RE) Institute, South Africa T Lamont --- Department of Environmental Affairs, South Africa M van den Berg --- Department of Environmental Affairs, South Africa SP Kirkman --- Department of Environmental Affairs, South AfricaThe development of suitable reference states for ecosystem-based management requires documentation of changes in structure and functioning of marine ecosystems, including assessment of the relative importance of bottom-up and top-down processes as drivers of change. We used monitoring data available... -
Seabird bycatch in the pelagic longline fishery off southern Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: SL Petersen --- , South Africa MB Honig --- , South Africa PG Ryan --- DST/NRF Centre of Excellence at the Percy FitzPatrick Institute of African Ornithology, South Africa LG Underhill --- Animal Demography Unit, Department of Zoology, South AfricaThe waters around South Africa provide rich foraging opportunities for pelagic seabirds. They also support a pelagic longline fleet targeting tunas Thunnus spp. and swordfish Xiphias gladius, which set a total of 41.5 million (average 5.2 million per year) and... -
Seabird bycatch in the demersal longline fishery off southern Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: SL Petersen --- , South Africa MB Honig --- , South Africa PG Ryan --- DST/NRF Centre of Excellence at the Percy FitzPatrick Institute of African Ornithology, South Africa LG Underhill --- Animal Demography Unit, Department of Zoology, South Africa M Goren --- , South AfricaThis study assesses seabird bycatch in the demersal longline hake (Merluccius capensis and M. paradoxus) fishery in the southern Benguela region. Observers collected seabird bycatch data from 2 412 sets (14 million hooks) in the South African fishery, accounting for... -
Congruent, decreasing trends of gentoo penguins and Crozet shags at sub-Antarctic Marion Island suggest food limitation through common environmental forcing
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: RJM Crawford --- Branch: Oceans and Coasts, Department of Environmental Affairs, South Africa BM Dyer --- Branch: Oceans and Coasts, Department of Environmental Affairs, South Africa L Upfold --- Branch: Oceans and Coasts, Department of Environmental Affairs, South Africa AB Makhado --- Branch: Oceans and Coasts, Department of Environmental Affairs, South AfricaNumbers of gentoo penguins Pygoscelis papua and Crozet shags Phalacrocorax [atriceps] melanogenis breeding annually at Marion Island, one of South Africa's Prince Edward Islands in the South-West Indian Ocean, were strongly correlated over 19 split-years from 1994/1995 to 2012/2013. Both... -
Winners and losers – responses to recent environmental change by South African seabirds that compete with purse-seine fisheries for food
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Robert JM Crawford --- Branch Oceans and Coasts, South Africa Azwianewi B Makhado --- Branch Oceans and Coasts, South Africa Lauren J Waller --- CapeNature, South Africa Philip A Whittington --- Department of Zoology, South AfricaThere were recent changes in the distributions of the main prey of four seabirds off South Africa, with sardine Sardinops sagax and anchovy Engraulis encrasicolus shifting from South Africa's north-west coast towards the south-east. This contributed to numbers of African... -
Lumbering the gauntlet: Cape Gannet fledglings killed by African Penguins
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Alistair M McInnes --- DST/NRF Centre of Excellence at the Percy FitzPatrick Institute of African Ornithology, South Africa Nicolas Suarez --- Centro Nacional Patagonico (CONICET), Argentina Gavin M Rishworth --- DST/NRF Centre of Excellence at the Percy FitzPatrick Institute of African Ornithology, Department of Zoology, South Africa David B Green --- DST/NRF Centre of Excellence at the Percy FitzPatrick Institute of African Ornithology, Department of Zoology, South Africa Pierre A Pistorius --- DST/NRF Centre of Excellence at the Percy FitzPatrick Institute of African Ornithology, Department of Zoology, South Africa Lorien Pichegru --- DST/NRF Centre of Excellence at the Percy FitzPatrick Institute of African Ornithology, Department of Zoology, South AfricaThis account presents the first known observations of Cape Gannet Morus capensis fledgling mortalities as a result of aggressive nest defence behaviour by African Penguins Spheniscus demersus. Observations were conducted in 2013 on Bird Island, Algoa Bay, South Africa –... -
Phenology, nest-site selection and breeding success of a North African colony of the yellow-legged gull, Larus michahellis
Item type: Journal Article • Journal: African Zoology • Authors: Afef Baaloudj --- Laboratoire de Recherche et de Conservation des Zones Humides University of Guelma, Algeria Farrah Samraoui --- Laboratoire de Recherche et de Conservation des Zones Humides University of Guelma, Algeria Ahmed H. Alfarhan --- Center of Excellence for Research in Biodiversity King Saud University, Saudi Arabia Boudjéma Samraoui --- Center of Excellence for Research in Biodiversity King Saud University, Saudi ArabiaGulls are good biological models to investigate anthropogenic changes affecting the environment. We studied the breeding ecology of a monospecific colony of yellow–legged gulls, Larus michahellis on the Algerian island of Srigina, during three consecutive years (2009–2011) and attempted to... -
An updated assessment of the seabird populations breeding at Príncipe and Tinhosas
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: An Bollen --- Azuria, Belgium Estrela Matilde --- Fundação Príncipe Trust, Nuno Barros --- Birdland – Birdwatching and Nature, PortugalThe Príncipe Autonomous Region is recognised as a marine biodiversity hotspot, although little is known about the status of its marine fauna. It holds most breeding seabirds of the tropical eastern Atlantic Ocean. Based on anecdotal accounts of increased fishing... -
Survival estimates for the greater crested tern Thalasseus bergii in southern Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: A Payo-Payo --- Group of Ecology and Animal Demography (GEDA), Spain A Sanz-Aguilar --- Group of Ecology and Animal Demography (GEDA), Spain D Gaglio --- Percy FitzPatrick Institute of African Ornithology, DST-NRF Centre of Excellence, South Africa RB Sherley --- Environment and Sustainability Institute, University of Exeter, United Kingdom TR Cook --- Percy FitzPatrick Institute of African Ornithology, DST-NRF Centre of Excellence, South Africa R Altwegg --- Statistics in Ecology, Environment and Conservation, Department of Statistical Sciences, and African Climate and Development Initiative, South Africa PG Ryan --- Percy FitzPatrick Institute of African Ornithology, DST-NRF Centre of Excellence, South AfricaThe nominate race of the greater crested tern Thalasseus bergii breeds only along the coast of the Benguela region (west coast) of southern Africa, where its population is increasing, in contrast to other species of breeding seabirds in the region... -
A survey of Great-winged Petrels Pterodroma macroptera breeding at sub-Antarctic Marion Island and a revised global population estimate
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Ben J Dilley --- , South Africa David W Hedding --- , South Africa Stefan Schoombie --- , South Africa Peter G Ryan --- , South AfricaAlthough burrow-nesting petrels are the most abundant group of seabirds in the Southern Ocean, their global populations are poorly known, because most species breed on remote islands. For example, there are no accurate estimates for Great-winged Petrel Pterodroma macroptera populations... -
Rats and prions at Tristan da Cunha Island
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Ben J Dilley --- , South Africa Delia Davies --- , South Africa Julian Repetto --- , United Kingdom (South Atlantic Ocean) George Swain --- , United Kingdom (South Atlantic Ocean) Peter G Ryan --- , South AfricaTristan da Cunha is a 96 km2 volcanic island in the South Atlantic Ocean. Black Rats Rattus rattus reached the island from a shipwreck in 1882 and their depredation of seabirds’ eggs and chicks are likely partly responsible for the... -
Investigating the influence of the extreme Indian Ocean Dipole on the 2020 influx of Red-necked Phalaropes Phalaropus lobatus in Kenya
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Raphaël Nussbaumer --- , Kenya Mathieu Gravey --- , Switzerland Améline Nussbaumer --- , Kenya Colin Jackson --- , KenyaOcean currents have wide-ranging impacts on seabird movement and survival. By extension, the extreme oscillations they are subject to, such as extreme Indian Ocean Dipole (IOD) events, can also be expected to dramatically influence seabird populations. This study links the... -
The names and naming of gannets comprising the genus Morus (family Sulidae)
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Adrian Koopman --- , South AfricaThe gannet species found in the northern hemisphere can be fully identified as the Northern Gannet Morus bassanus in the family Sulidae. This full identity reveals four historical themes which intertwine to produce a number of historical and current names... -
Natural recolonisation of sub-Antarctic Marion Island by Common Diving Petrels Pelecanoides urinatrix
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Maëlle Connan --- Marine Apex Predator Research Unit (MAPRU), Institute for Coastal and Marine Research, Nelson Mandela University, South Africa Stefan Schoombie --- Marine Apex Predator Research Unit (MAPRU), Institute for Coastal and Marine Research, Nelson Mandela University, South Africa Janine Schoombie --- FitzPatrick Institute of African Ornithology, DSI-NRF Centre of Excellence, University of Cape Town, South Africa Ben Dilley --- FitzPatrick Institute of African Ornithology, DSI-NRF Centre of Excellence, University of Cape Town, South Africa Peter G Ryan --- FitzPatrick Institute of African Ornithology, DSI-NRF Centre of Excellence, University of Cape Town, South AfricaNocturnal burrow-nesting seabirds are notoriously difficult to study and can go unnoticed for years in remote areas. One of these species is the Common Diving Petrel Pelecanoides urinatrix, which has a circumpolar breeding distribution in the Southern Ocean, including at...