Search
Search results for
We found
25 results for you
-
Records of the Subantarctic Fur Seal Arctocephalus Tropicalis from Rodrigues and Mauritius, Indian Ocean
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: J. H. M. David L. SalmonA juvenile Subantarctic fur seal Arctocephalus tropicalis was recorded on the Indian Ocean island of Rodrigues and two were seen on Mauritius. These records are at least 2 500 km from the closest breeding colony (Amsterdam Island) and are 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... -
Populations of Surface-nesting Seabirds at Marion Island, 1994/95–2002/03
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: R. J. M. Crawford J. Cooper B. M. Dyer M. D. Greyling N. T. W. Klages P. G. Ryan S. L. Petersen L. G. Underhill L. Upfold W. Wilkinson M. S. De Villiers S. Du Plessis M. Du Toit T. M. Leshoro A. B. Makhado M. S. Mason D. Merkle D. Tshingana V. L. Ward P. A. WhittingtonDuring the 1990s and early 2000s, populations of surface-nesting seabirds at Marion Island showed different trends, but for the majority of species numbers decreased. Reduced numbers of gentoo penguins Pygoscelis papua, eastern rockhopper penguins Eudyptes chrysocome filholi, Crozet shags Phalacrocorax... -
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... -
Unusual Breeding by Seabirds at Marion Island During 1997/98
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: R. J. M. Crawford C. M. Duncombe Rae D. C. Nel J. CooperIn 1997/98, breeding at subantarctic Marion Island was exceptionally good for five species of seabirds capable of foraging over wide areas and for a tern. The number of king penguin Aptenodytes patagonicus chicks surviving to the start of spring in... -
Population and Breeding of the Gentoo Penguin Pygoscelis Papua at Marion Island, 1994/95 – 2002/03
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: R. J. M. Crawford J. Cooper M. Du Toit M. D. Greyling B. Hanise C. L. Holness D. G. Keith J. L. Nel S. L. Petersen K. Spencer D. Tshingana A. C. WolfaardtThe numbers of gentoo penguins Pygoscelis papua breeding at subantarctic Marion Island fell by 40% from 1994/95 to 2002/03, from 1 352 pairs to 806 pairs. Apart from a slight increase in 1998/99, there was a steady decrease in numbers... -
Population of the Macaroni Penguin Eudyptes Chrysolophus at Marion Island, 1994/95–2002/03, with Information on Breeding and Diet
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: R. J. M. Crawford J. Cooper B. M. DyerThere is indication that numbers of macaroni penguins Eudyptes chrysolophus at subantarctic Marion Island have decreased since the early 1980s. Estimates of the population at the island fell from about 405 000 pairs in 1983/84 and 434 000 pairs in... -
Decrease in Numbers of the Eastern Rockhopper Penguin Eudyptes Chrysocome Filholi at Marion Island, 1994/95–2002/03
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: R. J. M. Crawford J. Cooper B. M. Dyer M. D. Greyling N. T. W. Klages D. C. Nel J. L. Nel S. L. Petersen A. C. WolfaardtThe number of eastern rockhopper penguins Eudyptes chrysocome filholi breeding at subantarctic Marion Island decreased from about 173 000 pairs in 1994/95 to about 67 000 pairs in 2001/02. During 1994/95 – 2002/03 pairs fledged on average 0.40 chicks per... -
Absence of Haematozoa in Breeding Macaroni Eudyptes Chrysolophus and Rockhopper E. Chrysocome Penguins at Marion Island
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: A. Schultz S. L. PetersenHaematozoan infections cause the death of penguins in captivity, but seldom in the wild. No haematozoa were found in 89 blood smears taken from macaroni penguins Eudyptes chrysolophus or 80 smears from eastern rockhopper penguins E. chrysocome filholi at subantarctic... -
Population Dynamics of the Wandering Albatross Diomedea Exulans at Marion Island: Longline Fishing and Environmental Influences
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: D. C. Nel F. Taylor P. G. Ryan J. CooperThe subantarctic Prince Edward Islands (Marion and Prince Edward) support the largest breeding population of the Vulnerable wandering albatross Diomedea exulans. The number of birds breeding at Marion Island has fluctuated over the past three decades apparently as a result... -
Exchange of the Wandering Albatross Diomedea Exulans Between the Prince Edward and Crozet Islands: Implications for Conservation
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: J. Cooper H. WeimerskirchExchange of 61 wandering albatrosses Diomedea exulans has been recorded between the French Crozet Islands and the South African Prince Edward Islands, 1 068 km apart in the Southern Ocean. Most movements of banded birds (57) have been westwards, from... -
The Oldest Known Banded Wandering Albatross Diomedea Exulans at the Prince Edward Islands
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: J. Cooper H. Battam C. Loves P. J. Milburn L. E. SmithThe oldest known wandering albatross Diomedea exulans at the Prince Edward Islands is estimated to have been approximately half a century old when last recaptured in 2001. Demographic studies need to continue for several more decades before the true maximum... -
Nest Densities of the Wandering Albatross Diomedea Exulans at the Prince Edward Islands, Estimated Using Gps
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: L. G. Underhill S. L. Petersen J. CooperHand-held Global Positioning System (GPS) receivers provide opportunities for detailed and rapid mapping of features, including biological ones, further enhanced by the removal during 2000 of "selective availability". GPS was used to map, describe and compare nest densities within wandering... -
Population, Breeding, Diet and Conservation of the Crozet Shag Phalacrocorax [atriceps] Melanogenis at Marion Island, 1994/95–2002/03
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: R. J. M. Crawford J. Cooper B. M. Dyer A. C. Wolfaardt D. Tshingana K. Spencer S. L. Petersen J. L. Nel D. G. Keith C. L. Holness B. Hanise M. D. Greyling M. Du ToitThe number of Crozet shags or cormorants Phalacrocorax [atriceps] melanogenis breeding at subantarctic Marion Island decreased by 68% from 841 pairs in 1994/95 to 272 pairs in 2002/03. The mean number of pairs at colonies also decreased and was significantly... -
Population Numbers of Fur Seals at Prince Edward Island, Southern Ocean
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: M. N. Bester P. G. Ryan B. M. DyerDuring the period 17–22 December 2001, the onshore distribution and the abundance of Antarctic fur seals Arctocephalus gazella and Subantarctic fur seals A. tropicalis were determined for Prince Edward Island. Two breeding colonies of Antarctic fur seals were located on... -
The Distribution and Spread of Alien Vascular Plants on Prince Edward Island
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: P. G. Ryan V. R. Smith N. J. M. GremmenSurveys of alien plants at subantarctic Prince Edward Island in 2001 show that the ranges of all three introduced species have increased since the last survey in 1998. Poa annua, the longest-established species, increased its range substantially after 1987, prior... -
The Marine Mammal Programme at the Prince Edward Islands: 38 years of research
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: MN Bester --- Department of Zoology and Entomology, University of Pretoria, South Africa PJN de Bruyn WC Oosthuizen CA Tosh T McIntyre RR Reisinger M Postma DS van der Merwe M WegeThe Marine Mammal Programme (MMP) conducts research on pinnipeds and killer whales Orcinus orca at Marion Island, Prince Edward Islands, under the auspices of the Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria. The history of the... -
Natal site fidelity by breeding female southern elephant seals in relation to their history of participation in the winter haulout
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: GJG Hofmeyr --- Mammal Research Institute, Department of Zoology & Entomology, South Africa SP Kirkman --- Mammal Research Institute, Department of Zoology & Entomology, South Africa PA Pistorius --- Mammal Research Institute, Department of Zoology & Entomology, South Africa MN Bester --- Mammal Research Institute, Department of Zoology & Entomology, South AfricaOf the four types of terrestrial haulout periods undertaken by southern elephant seals Mirounga leonina, only the purpose of the winter haulout is unknown. Returning to a haulout site from distant pelagic foraging grounds bears significant costs in terms of... -
The Bryozoa of subantarctic Marion and Prince Edward Islands: illustrated keys to the species and results of the 1982–1989 University of Cape Town surveys
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: ML Branch PJ HaywardThe Bryozoa of subantarctic Marion and Prince Edward Islands were sampled over the period 1982–1989 by dredging, SCUBA-diving and intertidal surveys. This paper comprises illustrated keys to all 82 species of Bryozoa collected during these and previous surveys, including 15... -
Summer survey of fur seals at Prince Edward Island, southern Indian Ocean
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: MN Bester --- Mammal Research Institute, Department of Zoology and Entomology, South Africa PG Ryan --- , South Africa J Visagie --- , South AfricaThe onshore distributions and the abundances of Antarctic fur seals Arctocephalus gazella and Subantarctic fur seals A. tropicalis were determined at Prince Edward Island during 16-20 December 2008. This repeats a survey conducted in December 2001 and extends the area... -
Vagrant Subantarctic fur seals at Bouvetøya
Item type: Journal Article • Journal: African Zoology • Authors: G. J. G. Hofmeyr --- Mammal Research Institute, Department of Zoology and Entomology, South Africa M. N. Bester --- Mammal Research Institute, Department of Zoology and Entomology, South Africa S. P. Kirkman --- Mammal Research Institute, Department of Zoology and Entomology, South AfricaThree vagrant Subantarctic fur seals, Arctocephalustropicalis, were seen amongst a colony of Antarctic fur seals, A. gazella, at the isolated subantarctic island, Bouvetøya. Possible sources of the vagrants are populations at either Gough Island or the Prince Edward Islands Archipelago. -
Goose barnacle (Lepas australis) infestation of the Subantarctic fur seal (Arctocephalus tropicalis)
Item type: Journal Article • Journal: African Zoology • Authors: T. H. Setsaas --- Mammal Research Institute, Department of Zoology and Entomology, South Africa M. N. Bester --- Mammal Research Institute, Department of Zoology and Entomology, South AfricaGoose barnacle infestations (Lepas australis) were found on the pelage of two female Subantarctic fur seals (Arctocephalus tropicalis) at Gough Island in the South Atlantic. The infested females were both relatively old at 11 and 15 years of age. We... -
Blue Petrels Halobaena caerulea discovered breeding on Gough Island
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Peter G Ryan --- Percy FitzPatrick Institute of African Ornithology, DST–NRF Centre of Excellence, South Africa Ben J Dilley --- Percy FitzPatrick Institute of African Ornithology, DST–NRF Centre of Excellence, South Africa Christopher Jones --- Percy FitzPatrick Institute of African Ornithology, DST–NRF Centre of Excellence, South Africa Alexander L Bond --- RSPB Centre for Conservation Science, UKThe Blue Petrel Halobaena caerulea breeds at five subantarctic island groups and at islands off southern Chile in a narrow latitudinal band from 47° to 56° S on either side of the Antarctic Polar Front. We found a colony on... -
Pup growth and maternal attendance patterns in Subantarctic fur seals
Item type: Journal Article • Journal: African Zoology • Authors: S.P Kirkman --- Mammal Research Institute, Department of Zoology and Entomology, South Africa M.N. Bester --- Mammal Research Institute, Department of Zoology and Entomology, South Africa G.J.G. Hofmeyr --- Mammal Research Institute, Department of Zoology and Entomology, South Africa P.A. Pistorius --- Mammal Research Institute, Department of Zoology and Entomology, South Africa A.B. Makhado --- Mammal Research Institute, Department of Zoology and Entomology, South AfricaSamples of pups from the expanding populations of Subantarctic fur seals (Arctocephalus tropicalis) atMarion and Gough islands were weighed at specific ages between birth and weaning in the period 1993-2000. Growth was estimated and compared between years, sexes, sites of... -
Long-term changes in petrel populations on Inaccessible Island, Tristan da Cunha, inferred from the diet of Brown Skuas Stercorarius antarcticus
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Peter G Ryan --- University of Cape Town, South AfricaPetrels that breed in burrows and return to their colonies after dark are among the most poorly studied seabirds. Brown Skuas Stercorarius antarcticus (family Stercorariidae) are major predators of burrowing petrels at many seabird breeding islands in the Southern Ocean,...