17 Result(s)
within
Peter G Ryan
Plant Sciences
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Article
Open AccessFirst evidence of mouse predation killing adult great albatrosses
Invasive rodents threaten native species in numerous ecosystems, especially oceanic islands. The House Mouse Mus musculus is the only introduced mammal species on sub-Antarctic Gough and Marion Islands. Ample evi...
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Article
Open AccessA juvenile Tristan albatross (Diomedea dabbenena) on land at the Crozet Islands
Albatrosses and other seabirds are generally highly philopatric, returning to natal colonies when they achieve breeding age. This is not universal, however, and cases of extraordinary vagrancy are rare. The Tr...
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Article
Plumage and bill abnormalities in albatross chicks on Marion Island
Accessible colonies of Grey-headed Albatross Thalassarche chrysostoma chicks on Marion Island have been inspected for chicks presenting mouse wounds from 2015, and during these inspections we found several cases ...
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Article
First evidence of mouse attacks on adult albatrosses and petrels breeding on sub-Antarctic Marion and Gough Islands
Invasive house mice Mus musculus are significant predators of seabird chicks on islands where they are the only introduced mammal, but there are very few records of attacks on adult birds. We report the first evi...
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Article
The foraging range of Great Shearwaters (Ardenna gravis) breeding on Gough Island
Ardenna shearwaters have among the most extreme foraging trips of any central place forager, yet little is known about the foraging range of the largest member of the genus, the Great Shearwater (Ardenna gravis)....
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Article
Status and trends of albatrosses in the French Southern Territories, Western Indian Ocean
Today albatrosses are threatened worldwide, especially by fishing activities, and many populations are currently in decline. Albatrosses breeding at the French Southern Territories in the south-western Indian ...
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Westward range extension of Short-tailed Shearwaters Ardenna tenuirostris in the Southern Ocean
Short-tailed Shearwaters Ardenna tenuirostris are transequatorial migrants that breed at islands in southern Australia and spend the austral winter in the North Pacific. Adults feeding chicks undertake long forag...
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Article
Wandering Albatross Diomedea exulans breeding phenology at Marion Island
South Africa’s Prince Edward Islands support a large proportion (44 %) of the global Wandering Albatross Diomedea exulans breeding population, yet most breeding phenology data are recorded from smaller and geogra...
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Article
Modest increases in densities of burrow-nesting petrels following the removal of cats (Felis catus) from Marion Island
Introduced predators are one of the main threats facing seabirds breeding on oceanic islands. Cats (Felis catus) were introduced to subantarctic Marion Island (290 km2) in 1949, and by the 1970s some 2000 cats we...
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Article
The role of eddies in the diving behaviour of female southern elephant seals
As the Antarctic Circumpolar Current crosses the South-West Indian Ocean Ridge, it creates an extensive eddy field characterised by high sea level anomaly variability. We investigated the diving behaviour of f...
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The effect of parental age, experience and historical reproductive success on wandering albatross (Diomedea exulans) chick growth and survival
Growth and survival of altricial young are influenced by their parents’ abilities to invest in a breeding attempt. As a result, chick growth and survival in one breeding season may be indicative of their paren...
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Article
The occurrence of two bill morphs of prions Pachyptila vittata on Gough Island
Prions Pachyptila are abundant seabirds in the Southern Ocean that have been used to infer environmental change, but this relies on an understanding of their morphological diversity. Species limits among prions a...
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Article
Giant petrels as predators of albatross chicks
Giant petrels Macronectes spp. are not thought to be important predators of albatross chicks, although they are known to kill pre-fledging Thalassarche and Phoebetria albatrosses. We report the first records of p...
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Diving patterns of female macaroni penguins breeding on Marion Island, South Africa
Despite the large biomass of macaroni penguins Eudyptes chrysolophus in the Southern Ocean, their feeding ecology is poorly known at some important breeding localities. We investigated the diving behaviour and di...
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Article
Using behavioural and state variables to identify proximate causes of population change in a seabird
Changes in animal population size are driven by the interactions between intrinsic processes and extrinsic forces, and identifying the proximate mechanisms behind population change remains a fundamental questi...
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Individual variability of behavioural responses by Wandering Albatrosses (Diomedea exulans) to human disturbance
Sub-Antarctic Marion Island has had a permanent research station for 50 years and the island’s Wandering Albatrosses have been intensively studied for 20 years. The reactions of breeding birds to approaches by...
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Population trends of albatrosses and petrels at sub-Antarctic Marion Island
We report on the population changes of five species of Procellariiform seabirds breeding at Marion Island: wandering albatross (Diomedea exulans), grey-headed albatross (Thalassarche chrysostoma), northern giant...
