The efficacy of hand-rearing penguin chicks: evidence from African Penguins (Spheniscus demersus) orphaned in the Treasure oil spill in 2000
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Abstract Some 2,000 orphaned chicks of African Penguins Spheniscus demersus were hand-reared and released back into the wild on Robben and Dassen Islands following the Treasure oil spill in June 2000. Of these chicks, 1,787 were flipper banded. This paper reports on the subsequent survival rate and breeding success of those individuals seen on Robben Island from 2001–2006. Survival to breeding age and their subsequent breeding success of hand-reared chicks was no different from that of naturally-reared chicks. Over a four-year period, pairs where at least one partner was a hand-reared chick produced an average of more than 1.6 chicks per year. Combining the data on survival with that on breeding success indicates that 1,000 hand-reared chicks will produce around 1,220 chicks themselves over their lifetimes, making this a worthwhile conservation intervention.
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The comparable subsequent breeding success of hand-reared and naturally-reared African penguins makes sub-clinical disease introduction unlikely.
“although the comparable subsequent breeding success of hand-reared and naturally-reared African penguins [17] makes this unlikely too.”
From Hand-Rearing, Release and Survival of African Penguin Chicks Abandoned Before Independence by Moulting Parents (2014) · cites this paper as [17]
The Abstract and Results report comparable subsequent breeding success for hand-reared and naturally-reared African penguins. The Discussion does not infer from this that sub-clinical disease introduction is unlikely; it identifies disease introduction as a risk that needs further investigation. Page numbers were not supplied in our copy. (LLM, conf=0.86)
Experimental — accuracy not yet measuredFirst-year survival of hand-reared abandoned chicks was within the range of estimates for chicks hand-reared after oil spills (0.20-0.42).
“Survival in the first year after release (0.32±0.08) was within the range of estimates for chicks hand-reared after oil spills (0.20–0.42, [17], [45])”
From Hand-Rearing, Release and Survival of African Penguin Chicks Abandoned Before Independence by Moulting Parents (2014) · cites this paper as [17]
The ‘Survival rates of hand-reared chicks’ section reports estimated survival after the Treasure oil spill and cautions that the 2000–2001 estimates are likely biased low. But the passages in our copy do not give a first-year survival estimate of 0.20 or 0.42; the reported 0.21 is a recapture rate, not a survival rate. Thus the paper supports the type of comparison, but not the stated numerical range. (LLM, conf=0.78)
Experimental — accuracy not yet measuredProlonged hand-feeding does not reduce fledging success in African penguins.
“this does not occur with African penguins”
From Hand-Rearing, Release and Survival of African Penguin Chicks Abandoned Before Independence by Moulting Parents (2014) · cites this paper as [17]
The Discussion (page unavailable) says hand-reared African Penguin chicks can be raised successfully to fledging and that they spend an average of 65 days at the rescue centre before release. It does not compare feeding durations or test whether prolonged hand-feeding affects fledging success, so it supports successful hand-rearing but not the specific duration claim. (LLM, conf=0.82)
Experimental — accuracy not yet measuredThe action of hand-rearing and release ultimately acted to reinforce the breeding population at the source colonies.
“suggesting that this action ultimately acted to reinforce the breeding population at the source colonies [17].”
From Hand-Rearing, Release and Survival of African Penguin Chicks Abandoned Before Independence by Moulting Parents (2014) · cites this paper as [17]
The Results report that hand-reared chicks returned and bred on Robben Island, supporting a contribution to that colony’s breeding population. The Introduction says the chicks’ natal islands were unknown, and the paper reports post-release breeding outcomes for Robben Island, not both source colonies. It therefore does not establish the claim for the source colonies collectively. (LLM, conf=0.84)
Experimental — accuracy not yet measuredApparent adult survival of hand-reared abandoned chicks was similar to estimates for chicks hand-reared after the 1994 (0.79) and 2000 oil spills.
“apparent adult survival (0.76±0.10) was also similar to estimates for chicks hand-reared after the 1994 (0.79, [45]) and 2000 oil spills [17].”
From Hand-Rearing, Release and Survival of African Penguin Chicks Abandoned Before Independence by Moulting Parents (2014) · cites this paper as [17]
The Abstract and 'Estimating survival of hand-reared chicks' section identify this as a study of survival among chicks hand-reared after the 2000 oil spill. The passages in our copy do not give an adult-survival estimate for that cohort with which to verify the claimed similarity to 0.76±0.10. The 82% rate in the Discussion is attributed to Crawford et al. (1999), not estimated for these hand-reared chicks. (LLM, conf=0.78)
Experimental — accuracy not yet measured
Chicks hand-reared after catastrophic oil spills had survival and recruitment rates analogous to naturally-reared cohorts and reproduced successfully once they entered the breeding population.
“Chicks hand-reared after catastrophic oil spills had survival and recruitment rates analogous to naturally-reared cohorts [17], [18] and reproduced successfully once they entered the breeding population [17].”
From Hand-Rearing, Release and Survival of African Penguin Chicks Abandoned Before Independence by Moulting Parents (2014) · cites this paper as [17]
Hand-reared African penguin chicks are as fit as naturally-reared chicks.
“because hand-reared chicks are as fit as naturally-reared chicks [17], [27]”
From Hand-Rearing, Release and Survival of African Penguin Chicks Abandoned Before Independence by Moulting Parents (2014) · cites this paper as [17]
The African penguin has been considered a promising candidate for reinforcement and conservation translocation.
“the species has been considered a promising candidate for reinforcement and conservation translocation [17].”
From Hand-Rearing, Release and Survival of African Penguin Chicks Abandoned Before Independence by Moulting Parents (2014) · cites this paper as [17]
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Cites
Parsons, N., & Underhill, L. (2005) · African Journal of Marine Science · doi:10.2989/18142320509504087 · Cited by 62 · see citing works
Self-citationPatterns 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
Self-citation
Flagged first, then by citations
Research works printed but not linked: 13
- Crawford, R. J. M., Boonstra, H. G. v. D., Dyer, B. M. and Upfold, L. (1995) Recolonization of Robben Island by African Penguins, 1983- 1992. Pp. 333-363 in P. Dann, I. Norman and P. Reilly, eds. The penguins: ecology and management. Chipping Norton, Australia: Surrey Beatty.
- Crawford, R. J. M., Mey ¨er, M. A., Underhill, L. G. and Upfold, L. (2004) Relocation of African Penguins to prevent their becom- ing oiled after the sinking of the Treasure, and the tracking of their return. Pp. 13-16 in S. Kuyper and A. J. Williams, eds. Proceedings of the penguin workshop following the sinking of the Treasure in June 2000. Cape Town: Avian Demography Unit, University of Cape Town.
- Crawford, R. J. M., Shannon, L. J. and Whittington, P. A. (1999) Population dynamics of the African Penguin Spheniscus demersus at Robben Island, South Africa. Mar. Ornithol. 27: 139-147.
- Gildenhuys, A. (1995) Capture, care and release of orphaned African Penguin chicks at Dassen Island. Pp. 18-20 in J. Barrett, Z. Erasmus and A. J. Williams, eds. Proceedings coastal oil spills: effects on penguin communities and rehabilitation procedures. Cape Town: Cape Nature Conservation.
- Kemp, A. C. (1995) The Hornbills: Bucerotiformes. Oxford: Oxford University Press.
- Seddon, P. J. and van Heezik, Y. M. (1993) Behaviour of the Jackass Penguin chick. Ostrich 64(1): 8-12.
- Shannon, L. J. and Crawford, R. J. M. (1999) Management of the African Penguin Spheniscus demersus 2 insights from modelling. Mar. Ornithol. 27: 119-128.
- Whittington, P. A. (2002) Survival and movements of African Penguins, especially after oiling. PhD thesis, University of Cape Town, South Africa.
- Whittington, P. A., Klages, N. T. W., Crawford, R. J. M., Wolfaardt, A. C. and Kemper, J. (2005a) Age at first breeding of the African Penguin. Ostrich 76: 14-20.
- Whittington, P. A., Randall, R. M., Randall, B. M., Wolfaardt, A. C., Crawford, R. J. M., Klages, N. T. W., Bartlett, P. A., Chesselet, Y. J. and Jones, R. (2005c) Patterns of movements of the African Penguin in South Africa and Namibia. Afr. J. Mar. Sci. 27: 215-229.
- Wilkinson, R. (2006) Hornbills -their captive management and in-situ conservation. Pp. 11-12 in B. Hiddinga and R. de Jong, eds. Proceedings Special Edition, EAZA Symposium 2006 on the occasion of Koen Brouwer's farewell to the EAZA Executive Office. Amsterdam: EAZA Executive Office.
- Wolfaardt, A. C. (2004) The capture and removal of clean penguins from Dassen Island. Pp. 8-13 in S. Kuyper and A. J. Williams, eds. Proceedings of the Penguin Workshop following the sinking of the Treasure in June 2000. Cape Town: Avian Demography Unit, University of Cape Town.
- Wolfaardt, A. C. (2007) The effects of oiling and rehabilitation on the breeding produc- tivity and annual moult and breeding cycle of African Penguins. PhD thesis, University of Cape Town, South Africa.
Cited by
Sorted by citations
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-citationSherley, 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-citation
- Authors
- Barham, P. J., Underhill, L. G., Crawford, R. J. M., Altwegg, R., Mario Leshoro, T., Bolton, D. A., Dyer, B. M., & Upfold, L.
- Affiliations
- University of Bristol (GB)
- University of Cape Town (ZA)
- Government of South Africa (ZA)
- Corresponding author
- Barham, Peter J.
- Venue
- Bird Conservation International
- Publisher
- Cambridge University Press (CUP)
- Published
- 2008-05-20
- Volume
- 18
- Issue
- 2
- Pages
- 144-152
- ISSN
- 0959-2709 (ISSN-L)
- 1474-0001
- OpenAlex
- W2130626267
- Cited by
- 32
- References
- 2
- Citations by year
- 2025: 1 · 2023: 3 · 2022: 1 · 2021: 1 · 2020: 1 · 2019: 2 · 2018: 5 · 2017: 3 · 2016: 1 · 2015: 4 · 2014: 5 · 2013: 2 · 2012: 1
- FWCI
- 0.58
- Type
- journal article
- Language
- en
- Open access
- bronze
- doi.org
- Locations
- Bird Conservation International (publishedVersion)
- Bristol Research (University of Bristol) (publishedVersion)
- Explore Bristol Research (submittedVersion)
- Funders
- Earthwatch Institute
- National Research Foundation
- Topics
- Physical Sciences › Environmental Science › Ecology › Avian ecology and behavior
- Physical Sciences › Environmental Science › Ecology › Marine animal studies overview
- Life Sciences › Agricultural and Biological Sciences › Ecology, Evolution, Behavior and Systematics › Animal Behavior and Reproduction
- Keywords
- hand-rearing, African penguin, Spheniscus demersus, oil spills, breeding success, seabird conservation, Robben Island, Dassen Island
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