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Factors impacting the breeding success of African penguins Spheniscus demersus on Robben Island

The African penguin Spheniscus demersus is a seabird endemic to the south-western coast of Africa and can be found in three main breeding localities; southern Namibia, the Western Cape and Algoa Bay, Eastern Cape, South Africa. The African penguin has been listed as Endangered since 2010, having exp...

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Main Author: Tol, Leanne
Other Authors: Underhill, Leslie G
Format: Thesis
Language:English
Published: Department of Biological Sciences 2016
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access_status_str Open Access
author Tol, Leanne
author2 Underhill, Leslie G
author_browse Tol, Leanne
Underhill, Leslie G
author_facet Underhill, Leslie G
Tol, Leanne
author_sort Tol, Leanne
collection Thesis
description The African penguin Spheniscus demersus is a seabird endemic to the south-western coast of Africa and can be found in three main breeding localities; southern Namibia, the Western Cape and Algoa Bay, Eastern Cape, South Africa. The African penguin has been listed as Endangered since 2010, having experienced a decline in population of more than 50% over the past three generations. This study was conducted at the breeding colony on Robben Island, South Africa, and examined two factors that have the potential to affect breeding success of African penguins; body mass at the onset of breeding and the suitability of various nest types to mitigate changing climatic conditions. Body mass was measured by recording weights using an automated weighing scale set up in front of a nest. Weights were taken at the start of breeding of each penguin in a breeding pair and these weights were compared to the number of chicks fledged, fledging period, hatching success, clutch size, and chick fledging weight. Hatching success, clutch size, and fledging weight were not influenced by the mass of either parent. There was a trend of shorter fledging periods as the mass of the heavier parent increased. The greatest effect was from the body mass of the lighter parent on the number of chicks that fledged from the nest; as the mass of the lightest adult increased, more chicks were fledged. If the lighter adult weighed below 2 kg there were always no chicks at the nest that fledged. This suggests evidence for a carry-over effect of body mass from the time before breeding starts into the breeding season, and highlights the importance of food availability for African penguins on a global scale, and not just a local one. The proportion of nest failures of six nest types (vegetation, open, natural burrow, building, wooden nest box, and artificial fibreglass burrow) at the incubation and chick-rearing stage were compared to rainfall and maximum temperature.
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institution University of Cape Town (South Africa)
language eng
last_indexed 2026-06-10T12:31:58.458Z
license_str Not specified — see source repository
provenance_str_mv Harvested via OAI-PMH from UCTD — University of Cape Town Open Access Repository
publishDate 2016
publishDateRange 2016
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publisher Department of Biological Sciences
publisherStr Department of Biological Sciences
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source_str UCTD — University of Cape Town Open Access Repository
spelling oai:open.uct.ac.za:11427/20873 Factors impacting the breeding success of African penguins Spheniscus demersus on Robben Island Tol, Leanne Underhill, Leslie G Barham, Peter Sherley, Richard Zoology Ornithology Marine Biology The African penguin Spheniscus demersus is a seabird endemic to the south-western coast of Africa and can be found in three main breeding localities; southern Namibia, the Western Cape and Algoa Bay, Eastern Cape, South Africa. The African penguin has been listed as Endangered since 2010, having experienced a decline in population of more than 50% over the past three generations. This study was conducted at the breeding colony on Robben Island, South Africa, and examined two factors that have the potential to affect breeding success of African penguins; body mass at the onset of breeding and the suitability of various nest types to mitigate changing climatic conditions. Body mass was measured by recording weights using an automated weighing scale set up in front of a nest. Weights were taken at the start of breeding of each penguin in a breeding pair and these weights were compared to the number of chicks fledged, fledging period, hatching success, clutch size, and chick fledging weight. Hatching success, clutch size, and fledging weight were not influenced by the mass of either parent. There was a trend of shorter fledging periods as the mass of the heavier parent increased. The greatest effect was from the body mass of the lighter parent on the number of chicks that fledged from the nest; as the mass of the lightest adult increased, more chicks were fledged. If the lighter adult weighed below 2 kg there were always no chicks at the nest that fledged. This suggests evidence for a carry-over effect of body mass from the time before breeding starts into the breeding season, and highlights the importance of food availability for African penguins on a global scale, and not just a local one. The proportion of nest failures of six nest types (vegetation, open, natural burrow, building, wooden nest box, and artificial fibreglass burrow) at the incubation and chick-rearing stage were compared to rainfall and maximum temperature. 2016-07-27T10:26:17Z 2016-07-27T10:26:17Z 2016 Master Thesis Masters MSc http://hdl.handle.net/11427/20873 eng application/pdf Department of Biological Sciences Faculty of Science University of Cape Town
spellingShingle Zoology
Ornithology
Marine Biology
Tol, Leanne
Factors impacting the breeding success of African penguins Spheniscus demersus on Robben Island
thesis_degree_str Master's
title Factors impacting the breeding success of African penguins Spheniscus demersus on Robben Island
title_full Factors impacting the breeding success of African penguins Spheniscus demersus on Robben Island
title_fullStr Factors impacting the breeding success of African penguins Spheniscus demersus on Robben Island
title_full_unstemmed Factors impacting the breeding success of African penguins Spheniscus demersus on Robben Island
title_short Factors impacting the breeding success of African penguins Spheniscus demersus on Robben Island
title_sort factors impacting the breeding success of african penguins spheniscus demersus on robben island
topic Zoology
Ornithology
Marine Biology
url http://hdl.handle.net/11427/20873
work_keys_str_mv AT tolleanne factorsimpactingthebreedingsuccessofafricanpenguinsspheniscusdemersusonrobbenisland