Age‐specific survival and movement among major African Penguin Spheniscus demersus colonies
Abstract
Reliable estimates of survival and dispersal are crucial to understanding population dynamics, but for seabirds, in which some individuals spend years away from land, mortality and emigration are often confounded. Multistate mark–recapture methods reduce bias by incorporating movement into the process of estimating survival. We used a multistate model to provide unbiased age‐specific survival and movement probabilities for the Endangered African PenguinSpheniscus demersusbased on 5281 nestlings and 31 049 adults flipper‐banded and resighted in the Western Cape, South Africa, between 1994 and 2012. Adult survival was initially high (≥ 0.74) but declined after 2003–2004 coincident with a reduction in the availability of SardineSardinops sagaxand AnchovyEngraulis encrasicoluson the west coast of South Africa. Juvenile survival was poorly estimated, but was lower and more variable than adult survival. Fidelity to the locality of origin varied over time, but was high in adults at Robben and Dassen islands (≥ 0.88) and above 0.55 for juvenile and immature Penguins at all localities. Movement occurred predominantly during 1994–2003 and was indicative of immigration to Robben and Dassen islands. Our results confirm that a prolonged period of adult mortality contributed to the observed decline in the African Penguin population and suggest a need for approaches operating over large spatial scales to ensure food security for marine top predators.
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Movement of juvenile African penguins is extensive and breeding at non-natal colonies occurs.
“Movement of juvenile penguins is extensive [30] and breeding at non-natal colonies occurs [6], [26].”
From Hand-Rearing, Release and Survival of African Penguin Chicks Abandoned Before Independence by Moulting Parents (2014) · cites this paper as [6]
Juvenile survival of hand-reared abandoned chicks was towards the upper end of estimates for both juvenile (0.06-0.52) and adult (0.46-0.77) survival at these colonies during the study period.
“and was towards the upper end of estimates for both juvenile (0.06–0.52) and adult (0.46–0.77) survival at these colonies during our study period [3], [6].”
From Hand-Rearing, Release and Survival of African Penguin Chicks Abandoned Before Independence by Moulting Parents (2014) · cites this paper as [6]
The situation for African penguin has continued to deteriorate on the West Coast.
“As the situation for African penguin has continued to deteriorate on the West Coast [3], [6]”
From Hand-Rearing, Release and Survival of African Penguin Chicks Abandoned Before Independence by Moulting Parents (2014) · cites this paper as [6]
If poor prey availability persists, the subsequent survival and reproductive success of these birds would be compromised relative to birds at colonies where conditions are more favourable.
“However, if the poor prey availability persists, their subsequent survival and reproductive success would be compromised relative to birds at colonies where conditions are more favourable [3], [6], [8].”
From Hand-Rearing, Release and Survival of African Penguin Chicks Abandoned Before Independence by Moulting Parents (2014) · cites this paper as [6]
African Penguin adult and juvenile survival probabilities fluctuate and have recently dropped to <0.4.
“However, African Penguin adult and juvenile survival probabilities fluctuate and have recently dropped to <0.4 (Sherley et al. 2014).”
From Colour Abberations in African Penguins Spheniscus Demersus (2018) · cites this paper as Sherley et al. 2014
Cites
Collapse of South Africa's penguins in the early 21st century
Crawford, R., Altwegg, R., Barham, B., Barham, P., Durant, J., Dyer, B., Geldenhuys, D., Makhado, A., Pichegru, L., Ryan, P., et al. (2011) · African Journal of Marine Science · doi:10.2989/1814232x.2011.572377 · Cited by 165 · see citing works
Self-citationCrawford, R. J. M., Barham, P. J., Underhill, L. G., Shannon, L. J., Coetzee, J. C., Dyer, B. M., Leshoro, T. M., & Upfold, L. (2006) · Biological Conservation · doi:10.1016/j.biocon.2006.03.019 · Cited by 108 · see citing works
Sherley, R., Underhill, L., Barham, B., Barham, P., Coetzee, J., Crawford, R., Dyer, B., Leshoro, T., & Upfold, L. (2013) · Marine Ecology Progress Series · doi:10.3354/meps10070 · Cited by 65 · see citing works
Self-citationCrawford, R. J., Makhado, A. B., Waller, L. J., & Whittington, P. A. (2014) · Ostrich · doi:10.2989/00306525.2014.955141 · Cited by 39 · see citing works
Patterns of immigration to and emigration from breeding colonies by African penguins
Whittington, P., Randall, R., Crawford, R., Wolfaardt, A., Klages, N., Randall, B., Bartlett, P., Chesselet, Y., & Jones, R. (2005) · African Journal of Marine Science · doi:10.2989/18142320509504079 · Cited by 25 · see citing works
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Crawford, R. J., Makhado, A. B., Waller, L. J., & Whittington, P. A. (2014) · Ostrich · doi:10.2989/00306525.2014.955141 · Cited by 39 · see citing works
Sherley, R. B., Waller, L. J., Strauss, V., Geldenhuys, D., Underhill, L. G., & Parsons, N. J. (2014) · PLoS ONE · doi:10.1371/journal.pone.0110794 · Cited by 34 · see citing works
Self-citationThe African Penguin <i>Spheniscus demersus</i> should be considered Critically Endangered
Sherley, R. B., Makhado, A. B., Crawford, R. J., Hagen, C., Kemper, J., Ludynia, K., Masotla, M. J., McInnes, A., Pichegru, L., Tom, D., et al. (2024) · Ostrich · doi:10.2989/00306525.2024.2355618 · Cited by 23 · see citing works
Self-citationLudynia, K., Waller, L., Sherley, R., Abadi, F., Galada, Y., Geldenhuys, D., Crawford, R., Shannon, L., & Jarre, A. (2014) · African Journal of Marine Science · doi:10.2989/1814232x.2014.929027 · Cited by 17 · see citing works
Self-citationColour Abberations in African Penguins Spheniscus Demersus
Traisnel, G., Pichegru, L., Visser, H., & Edwards, L. (2018) · Marine Ornithology · doi:10.5038/2074-1235.46.1.1243 · Cited by 1 · see citing works
- Authors
- Sherley, R. B., Abadi, F., Ludynia, K., Barham, B. J., Clark, A. E., & Altwegg, R.
- Affiliations
- University of Cape Town (ZA)
- University of Bristol (GB)
- Corresponding author
- Sherley, Richard B.
- Venue
- Ibis
- Publisher
- Wiley
- Published
- 2014-08-22
- Volume
- 156
- Issue
- 4
- Pages
- 716-728
- ISSN
- 0019-1019 (ISSN-L)
- 1474-919X
- OpenAlex
- W2024253035
- Cited by
- 52
- References
- 5
- Citations by year
- 2026: 5 · 2025: 3 · 2024: 3 · 2023: 3 · 2022: 6 · 2021: 4 · 2020: 2 · 2019: 6 · 2018: 4 · 2017: 4 · 2016: 3 · 2015: 5 · 2014: 4
- FWCI
- 4.62
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- Ibis (publishedVersion)
- Funders
- National Research Foundation (85802)
- Claude Leon Foundation
- BirdLife South Africa
- Leiden Conservation Foundation
- Topics
- Physical Sciences › Environmental Science › Ecology › Avian ecology and behavior
- Physical Sciences › Environmental Science › Ecology › Marine animal studies overview
- Physical Sciences › Environmental Science › Global and Planetary Change › Marine and fisheries research
- Keywords
- African penguin, Spheniscus demersus, age-specific survival, dispersal, seabird population decline, juvenile survival, immigration, Robben Island, Dassen Island, Western Cape
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