Collapse of South Africa's penguins in the early 21st century

Crawford, RJM; Altwegg, R; Barham, BJ; Barham, PJ; Durant, JM; Dyer, BM; Geldenhuys, D; Makhado, AB; Pichegru, L; Ryan, PG; Underhill, LG; Upfold, L; Visagie, J; Waller, LJ; Whittington, PA

doi:10.2989/1814232x.2011.572377

Cited by 166Avian ecology and behaviorMarine animal studies overviewMarine and fisheries research

Collapse of South Africa's penguins in the early 21st century

Crawford, RJM, Altwegg, R, Barham, BJ, Barham, PJ, Durant, JM, Dyer, BM, Geldenhuys, D, Makhado, AB +7 more·2011·African Journal of Marine Science

DOI 10.2989/1814232x.2011.572377

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Abstract

The number of African penguins Spheniscus demersus breeding in South Africa collapsed from about 56 000 pairs in 2001 to some 21 000 pairs in 2009, a loss of 35 000 pairs (>60%) in eight years. This reduced the global population to 26 000 pairs, when including Namibian breeders, and led to classification of the species as Endangered. In South Africa, penguins breed in two regions, the Western Cape and Algoa Bay (Eastern Cape), their breeding localities in these regions being separated by c. 600 km. Their main food is anchovy Engraulis encrasicolus and sardine Sardinops sagax, which are also the target of purse-seine fisheries. In Algoa Bay, numbers of African penguins halved from 21 000 pairs in 2001 to 10 000 pairs in 2003. In the Western Cape, numbers decreased from a mean of 35 000 pairs in 2001–2005 to 11 000 pairs in 2009. At Dassen Island, the annual survival rate of adult penguins decreased from 0.70 in 2002/2003 to 0.46 in 2006/2007; at Robben Island it decreased from 0.77 to 0.55 in the same period. In both the Western and Eastern Cape provinces, long-term trends in numbers of penguins breeding were significantly related to the combined biomass of anchovy and sardine off South Africa. However, recent decreases in the Western Cape were greater than expected given a continuing high abundance of anchovy. In this province, there was a south-east displacement of prey around 2000, which led to a mismatch in the distributions of prey and the western breeding localities of p…

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The African penguin is classified as Endangered following a decrease in the global population of more than 70% between 2001 and 2013.
“The African penguin Spheniscus demersus is ‘Endangered’ following a decrease in the global population of >70% between 2001 and 2013 [3], [4].”
From Hand-Rearing, Release and Survival of African Penguin Chicks Abandoned Before Independence by Moulting Parents (2014) · cites this paper as [3]
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 [3]
Juvenile African penguins may emigrate to non-natal colonies if the food environment is heterogeneous.
“This was despite evidence that juvenile African penguins may emigrate to non-natal colonies if the food environment is heterogeneous [3], [5]”
From Hand-Rearing, Release and Survival of African Penguin Chicks Abandoned Before Independence by Moulting Parents (2014) · cites this paper as [3]
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 [3]
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 [3]

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Global Seabird Response to Forage Fish Depletion—One-Third for the Birds
Cury, P. M., Boyd, I. L., Bonhommeau, S., Anker‐Nilssen, T., Crawford, R. J. M., Furness, R. W., Mills, J. A., Murphy, E. J., Österblom, H., Paleczny, M., et al. (2011) · Science · doi:10.1126/science.1212928 · Cited by 694 · see citing works
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Pollution, habitat loss, fishing, and climate change as critical threats to penguins
Trathan, P. N., Borboroglu, P. G., Boersma, P. D., Bost, C., Crawford, R. J. M., Crossin, G. T., Cuthbert, R., Dann, P., Davis, L. S., de la Puente, S., et al. (2014) · Conservation Biology · doi:10.1111/cobi.12349 · Cited by 245 · see citing works
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Jellyfication of Marine Ecosystems as a Likely Consequence of Overfishing Small Pelagic Fishes: Lessons from the Benguela
Roux, J.-P., van der Lingen, C. D., Gibbons, M. J., MOROFF, N. E., Shannon, L. J., Smith, A. D. M., & Cury, P. M. (2013) · Bulletin of Marine Science · doi:10.5343/bms.2011.1145 · Cited by 149 · see citing works
Happy Feet in a Hostile World? The Future of Penguins Depends on Proactive Management of Current and Expected Threats
Ropert‐Coudert, Y., Chiaradia, A., Ainley, D. G., Barbosa, A., Boersma, P. D., Brasso, R. L., Dewar, M., Ellenberg, U., Borboroglu, P. G., Emmerson, L., et al. (2019) · Frontiers in Marine Science · doi:10.3389/fmars.2019.00248 · Cited by 148 · see citing works
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Ecosystem change in the southern Benguela and the underlying processes
Blamey, L. K., Shannon, L. J., Bolton, J. J., Crawford, R. J. M., Dufois, F., Evers-King, H., Griffiths, C. L., Hutchings, L., Jarre, A., Rouault, M. P., et al. (2014) · Journal of Marine Systems · doi:10.1016/j.jmarsys.2014.11.006 · Cited by 137 · see citing works
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Synthesis: climate effects on biodiversity, abundance and distribution of marine organisms in the B enguela
Jarre, A., Hutchings, L., Kirkman, S. P., Kreiner, A., Tchipalanga, P. C. M., Kainge, P., Uanivi, U., van der Plas, A. K., Blamey, L. K., Coetzee, J., et al. (2015) · Fisheries Oceanography · doi:10.1111/fog.12086 · Cited by 110 · see citing works
Tangled and drowned: a global review of penguin bycatch in fisheries
Crawford, R. M. B., Ellenberg, U., Frere, E., Hagen, C., Baird, K., Brewin, P. E., Crofts, S., Glass, J., Mattern, T., Pompert, J., et al. (2017) · Endangered Species Research · doi:10.3354/esr00869 · Cited by 109 · see citing works
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Industrial fishing, no-take zones and endangered penguins
Pichegru, L., Ryan, P. G., van Eeden, R., Reid, T. A., Grémillet, D., & Wanless, R. M. (2011) · Biological Conservation · doi:10.1016/j.biocon.2011.12.013 · Cited by 100 · see citing works
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Best practices for assessing forage fish fisheries-seabird resource competition
Sydeman, W. J., Thompson, S. A., Anker‐Nilssen, T., Arimitsu, M. L., Bennison, A., Bertrand, S., Boersch‐Supan, P. H., Boyd, C., Bransome, N. C., Crawford, R. J. M., et al. (2017) · Fisheries Research · doi:10.1016/j.fishres.2017.05.018 · Cited by 78 · see citing works
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Bayesian inference reveals positive but subtle effects of experimental fishery closures on marine predator demographics
Sherley, R. B., Barham, B. J., Barham, P., Campbell, K. J., Crawford, R. J. M., Grigg, J. L., Horswill, C., McInnes, A., Morris, T. L., Pichegru, L., et al. (2018) · Proceedings of the Royal Society B Biological Sciences · doi:10.1098/rspb.2017.2443 · Cited by 76 · see citing works
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Group foraging increases foraging efficiency in a piscivorous diver, the African penguin
McInnes, A., McGeorge, C., Ginsberg, S., Pichegru, L., & Pistorius, P. A. (2017) · Royal Society Open Science · doi:10.1098/rsos.170918 · Cited by 70 · see citing works
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Quantifying the projected impact of the South African sardine fishery on the Robben Island penguin colony
Robinson, W. M., Butterworth, D. S., & Plagányi, É. E. (2015) · ICES Journal of Marine Science · doi:10.1093/icesjms/fsv035 · Cited by 68 · see citing works
Influence of local and regional prey availability on breeding performance of African penguins Spheniscus demersus
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
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Avian Influenza H5N8 Outbreak in African Penguins (Spheniscus demersus), Namibia, 2019
Molini, U., Aikukutu, G., Roux, J.-P., Kemper, J., Ntahonshikira, C., Marruchella, G., Khaiseb, S., Cattoli, G., & Dundon, W. G. (2019) · Journal of Wildlife Diseases · doi:10.7589/2019-03-067 · Cited by 65 · see citing works
Revisiting the Effect of Capture Heterogeneity on Survival Estimates in Capture-Mark-Recapture Studies: Does It Matter?
Abadi, F., Botha, A. J., & Altwegg, R. (2013) · PLoS ONE · doi:10.1371/journal.pone.0062636 · Cited by 61 · see citing works
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Starving seabirds: unprofitable foraging and its fitness consequences in Cape gannets competing with fisheries in the Benguela upwelling ecosystem
Grémillet, D., Péron, C., Kato, A., Amélineau, F., Ropert‐Coudert, Y., Ryan, P. G., & Pichegru, L. (2016) · Marine Biology · doi:10.1007/s00227-015-2798-2 · Cited by 59 · see citing works
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The conservation status and population decline of the African penguin deconstructed in space and time
Sherley, R. B., Crawford, R. J. M., de Blocq, A. D., Dyer, B. M., Geldenhuys, D., Hagen, C., Kemper, J., Makhado, A. B., Pichegru, L., Tom, D., et al. (2020) · Ecology and Evolution · doi:10.1002/ece3.6554 · Cited by 60 · see citing works
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Blood parasites of penguins: a critical review
Vanstreels, R. E. T., Braga, É. M., & Catão‐Dias, J. L. (2016) · Parasitology · doi:10.1017/s0031182016000251 · Cited by 58 · see citing works
A synthesis of three decades of socio-ecological change in False Bay, South Africa: setting the scene for multidisciplinary research and management
Pfaff, M. C., Logston, R., Raemaekers, S., Hermes, J. C., Blamey, L. K., Cawthra, H. C., Colenbrander, D. R., Crawford, R. J. M., Day, E., du Plessis, N., et al. (2019) · Elementa Science of the Anthropocene · doi:10.1525/elementa.367 · Cited by 60 · see citing works
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St Helena Bay (southern Benguela) then and now: muted climate signals, large human impact
Hutchings, L., Jarre, A., Lamont, T., van den Berg, M., & Kirkman, S. P. (2012) · African Journal of Marine Science · doi:10.2989/1814232x.2012.689672 · Cited by 59 · see citing works
Avoidance of seismic survey activities by penguins
Pichegru, L., Nyengera, R., McInnes, A., & Pistorius, P. A. (2017) · Scientific Reports · doi:10.1038/s41598-017-16569-x · Cited by 57 · see citing works
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The Namibian Islands’ Marine Protected Area: Using seabird tracking data to define boundaries and assess their adequacy
Ludynia, K., Kemper, J., & Roux, J.-P. (2012) · Biological Conservation · doi:10.1016/j.biocon.2011.11.014 · Cited by 57 · see citing works
The Vocal Repertoire of the African Penguin (Spheniscus demersus): Structure and Function of Calls
Favaro, L., Ozella, L., & Pessani, D. (2014) · PLoS ONE · doi:10.1371/journal.pone.0103460 · Cited by 56 · see citing works
A comprehensive assessment of mercury exposure in penguin populations throughout the Southern Hemisphere: Using trophic calculations to identify sources of population-level variation
Brasso, R. L., Chiaradia, A., Polito, M. J., Rey, A. R., & Emslie, S. D. (2015) · Marine Pollution Bulletin · doi:10.1016/j.marpolbul.2015.05.059 · Cited by 55 · see citing works
A changing distribution of seabirds in South Africa—the possible impact of climate and its consequences
Crawford, R. J. M., Makhado, A. B., Whittington, P. A., Randall, R. M., Oosthuizen, W. H., & Waller, L. J. (2015) · Frontiers in Ecology and Evolution · doi:10.3389/fevo.2015.00010 · Cited by 54 · see citing works
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Age‐specific survival and movement among major African PenguinSpheniscus demersuscolonies
Sherley, R. B., Abadi, F., Ludynia, K., Barham, B. J., Clark, A. E., & Altwegg, R. (2014) · Ibis · doi:10.1111/ibi.12189 · Cited by 52 · see citing works
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Chlorinated, brominated and fluorinated organic pollutants in African Penguin eggs: 30 years since the previous assessment
Bouwman, H., Govender, D., Underhill, L. G., & Polder, A. (2015) · Chemosphere · doi:10.1016/j.chemosphere.2014.12.071 · Cited by 50 · see citing works
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Artificial nests enhance the breeding productivity of African Penguins ( Spheniscus demersus ) on Robben Island, South Africa
Sherley, R. B., Barham, B. J., Barham, P. J., Leshoro, T. M., & Underhill, L. G. (2012) · Emu - Austral Ornithology · doi:10.1071/mu11055 · Cited by 48 · see citing works
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A system dynamics approach to modelling multiple drivers of the African penguin population on Robben Island, South Africa
Weller, F. G., Cecchini, L.-A., Shannon, L. J., Sherley, R. B., Crawford, R. J. M., Altwegg, R., Scott, L., Stewart, T. J., & Jarre, A. (2014) · Ecological Modelling · doi:10.1016/j.ecolmodel.2014.01.013 · Cited by 46 · see citing works
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Sex-specific foraging behaviour and a field sexing technique for Endangered African penguins
Pichegru, L., Cook, T. R., Handley, J., Voogt, N., Watermeyer, J. P., Nupen, L. J., & McQuaid, C. D. (2012) · Endangered Species Research · doi:10.3354/esr00477 · Cited by 46 · see citing works
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Applying science to pressing conservation needs for penguins
Boersma, P. D., Borboroglu, P. G., Gownaris, N. J., Bost, C., Chiaradia, A., Ellis, S., Schneider, T., Seddon, P. J., Simeone, A., Trathan, P. N., et al. (2019) · Conservation Biology · doi:10.1111/cobi.13378 · Cited by 44 · see citing works
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Novel relapsing fever Borrelia detected in African penguins (Spheniscus demersus) admitted to two rehabilitation centers in South Africa
Yabsley, M. J., Parsons, N. J., Horne, E. C., Shock, B. C., & Purdee, M. (2011) · Parasitology Research · doi:10.1007/s00436-011-2602-2 · Cited by 42 · see citing works
Assessing risks to marine ecosystems with indicators, ecosystem models and experts
Bland, L. M., Watermeyer, K. E., Keith, D. A., Nicholson, E., Regan, T. J., & Shannon, L. J. (2018) · Biological Conservation · doi:10.1016/j.biocon.2018.08.019 · Cited by 42 · see citing works
Winners and losers – responses to recent environmental change by South African seabirds that compete with purse-seine fisheries for food
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
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Dietary change in Cape gannets reflects distributional and demographic shifts in two South African commercial fish stocks
Green, D., Klages, N., Crawford, R., Coetzee, J., Dyer, B., Rishworth, G., & Pistorius, P. (2015) · ICES Journal of Marine Science · doi:10.1093/icesjms/fsu203 · Cited by 42 · see citing works
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Maritime traffic trends around the southern tip of Africa – Did marine noise pollution contribute to the local penguins' collapse?
Pichegru, L., Vibert, L., Thiebault, A., Charrier, I., Stander, N., Ludynia, K., Lewis, M., Carpenter‐Kling, T., & McInnes, A. (2022) · The Science of The Total Environment · doi:10.1016/j.scitotenv.2022.157878 · Cited by 38 · see citing works
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Key Challenges in Advancing an Ecosystem-Based Approach to Marine Spatial Planning Under Economic Growth Imperatives
Lombard, A. T., Dorrington, R. A., Reed, J. R., Ortega‐Cisneros, K., Penry, G. S., Pichegru, L., Smit, K. P., Vermeulen-Miltz, E., Witteveen, M., Sink, K. J., et al. (2019) · Frontiers in Marine Science · doi:10.3389/fmars.2019.00146 · Cited by 37 · see citing works
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Reviewing evidence of marine ecosystem change off South Africa
Moloney, C. L., Fennessy, S. T., Gibbons, M. J., Roychoudhury, A. N., Shillington, F. A., von der Heyden, B. P., & Watermeyer, K. E. (2013) · African Journal of Marine Science · doi:10.2989/1814232x.2013.836135 · Cited by 37 · see citing works
Local forage fish abundance influences foraging effort and offspring condition in an endangered marine predator
Campbell, K. J., Steinfurth, A., Underhill, L. G., Coetzee, J., Dyer, B. M., Ludynia, K., Makhado, A. B., Merkle, D., Rademan, J., Upfold, L., et al. (2019) · Journal of Applied Ecology · doi:10.1111/1365-2664.13409 · Cited by 35 · see citing works
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Hand-Rearing, Release and Survival of African Penguin Chicks Abandoned Before Independence by Moulting Parents
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
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System dynamics modelling of the Endangered African penguin populations on Dyer and Robben islands, South Africa
Weller, F. G., Sherley, R. B., Waller, L. J., Ludynia, K., Geldenhuys, D., Shannon, L. J., & Jarre, A. (2016) · Ecological Modelling · doi:10.1016/j.ecolmodel.2016.01.011 · Cited by 32 · see citing works
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Small pelagic fish responses to fine-scale oceanographic conditions: implications for the endangered African penguin
McInnes, A., Ryan, P. G., Lacerda, M., Deshayes, J., Goschen, W. S., & Pichegru, L. (2017) · Marine Ecology Progress Series · doi:10.3354/meps12089 · Cited by 32 · see citing works
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Effect of weather conditions and presence of visitors on adrenocortical activity in captive African penguins (Spheniscus demersus)
Ozella, L., Anfossi, L., Di Nardo, F., & Pessani, D. (2017) · General and Comparative Endocrinology · doi:10.1016/j.ygcen.2015.12.002 · Cited by 32 · see citing works
Multi-predator assemblages, dive type, bathymetry and sex influence foraging success and efficiency in African penguins
Sutton, G. J., Pichegru, L., Botha, J. A., Kouzani, A. Z., Adams, S. D., Bost, C., & Arnould, J. P. Y. (2020) · PeerJ · doi:10.7717/peerj.9380 · Cited by 31 · see citing works
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Extreme microclimate conditions in artificial nests for Endangered African Penguins
Lei, B. R., Green, J. A., & Pichegru, L. (2014) · Bird Conservation International · doi:10.1017/s0959270913000671 · Cited by 30 · see citing works
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Bio-telemetry as an Essential Tool in Movement Ecology and Marine Conservation
Heylen, B. C., & Nachtsheim, D. A. (2018) · Springer eBooks · doi:10.1007/978-3-319-93284-2_7 · Cited by 29 · see citing works
African PenguinsSpheniscus demersus, Bait Balls and the Allee Effect
Ryan, P. G., Edwards, L., & Pichegru, L. (2012) · Ardea · doi:10.5253/078.100.0113 · Cited by 29 · see citing works
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Assessment of microsatellite and SNP markers for parentage assignment in ex situ African Penguin (Spheniscus demersus) populations
Labuschagne, C., Nupen, L. J., Kotzé, A., Grobler, J. P., & Dalton, D. L. (2015) · Ecology and Evolution · doi:10.1002/ece3.1600 · Cited by 29 · see citing works
Food habits of an endangered seabird indicate recent poor forage fish availability off western South Africa
Crawford, R. J. M., Sydeman, W. J., Thompson, S. A., Sherley, R. B., & Makhado, A. B. (2019) · ICES Journal of Marine Science · doi:10.1093/icesjms/fsz081 · Cited by 25 · see citing works
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Are African penguins worth saving? The ecotourism value of the Boulders Beach colony
Lewis, S., Turpie, J. K., & Ryan, P. G. (2012) · African Journal of Marine Science · doi:10.2989/1814232x.2012.716008 · Cited by 27 · see citing works
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Sex allocation and sex‐specific parental investment in an endangered seabird
Spelt, A., & Pichegru, L. (2016) · Ibis · doi:10.1111/ibi.12457 · Cited by 27 · see citing works
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African Penguin tolerance to humans depends on historical exposure at colony level
PICHEGRU, L., EDWARDS, T. B., DILLEY, B. J., FLOWER, T. P., & RYAN, P. G. (2016) · Bird Conservation International · doi:10.1017/s0959270915000313 · Cited by 26 · see citing works
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Luck in Food Finding Affects Individual Performance and Population Trajectories
Wilson, R. P., Neate, A., Holton, M. D., Shepard, E. L. C., Scantlebury, D. M., Lambertucci, S. A., di Virgilio, A., Crooks, E., Mulvenna, C. C., & Marks, N. J. (2018) · Current Biology · doi:10.1016/j.cub.2018.10.034 · Cited by 26 · see citing works
Increasing breeding success of an Endangered penguin: artificial nests or culling predatory gulls?
Pichegru, L. (2012) · Bird Conservation International · doi:10.1017/s0959270912000135 · Cited by 25 · see citing works
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Factors affecting adult survival and inter-colony movement at the three South African colonies of Cape gannet
Distiller, G. B., Altwegg, R., Crawford, R., Klages, N. T. W., & Barham, B. J. (2012) · Marine Ecology Progress Series · doi:10.3354/meps09807 · Cited by 25 · see citing works
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PROGNOSTIC INDICATORS OF REHABILITATION OUTCOMES FOR ADULT AFRICAN PENGUINS (SPHENISCUS DEMERSUS)
Parsons, N. J., Vanstreels, R. E. T., & Schaefer, A. M. (2017) · Journal of Wildlife Diseases · doi:10.7589/2017-06-146 · Cited by 25 · see citing works
Patterns of Distribution and Spatial Indicators of Ecosystem Change Based on Key Species in the Southern Benguela
Watermeyer, K. E., Hutchings, L., Jarre, A., & Shannon, L. J. (2016) · PLoS ONE · doi:10.1371/journal.pone.0158734 · Cited by 24 · see citing works
From incubation to release: Hand-rearing as a tool for the conservation of the endangered African penguin
Klusener, R., Hurtado, R., Parsons, N. J., Vanstreels, R. E. T., Stander, N., van der Spuy, S., & Ludynia, K. (2018) · PLoS ONE · doi:10.1371/journal.pone.0205126 · Cited by 24 · see citing works
Fine-scale foraging cues for African penguins in a highly variable marine environment
van Eeden, R., Reid, T. A., Ryan, P. G., & Pichegru, L. (2015) · Marine Ecology Progress Series · doi:10.3354/meps11557 · Cited by 24 · see citing works
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Health evaluation of African penguins (Spheniscus demersus) in southern Africa
Parsons, N. J., Gous, T. A., Schaefer, A. M., & Vanstreels, R. E. T. (2016) · Onderstepoort Journal of Veterinary Research · doi:10.4102/ojvr.v83i1.1147 · Cited by 24 · see citing works
Bottom-up and top-down control of the Benguela ecosystem's seabirds
Crawford, R. J. M., Makhado, A. B., & Oosthuizen, W. H. (2017) · Journal of Marine Systems · doi:10.1016/j.jmarsys.2017.04.004 · Cited by 23 · see citing works
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The African Penguin Spheniscus demersus 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
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Boldness at the nest predicts foraging and diving behaviour of female but not male African penguins
Traisnel, G., & Pichegru, L. (2019) · Animal Behaviour · doi:10.1016/j.anbehav.2019.02.003 · Cited by 23 · see citing works
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Phylogenetic relationships in southern African Bryde’s whales inferred from mitochondrial DNA: further support for subspecies delineation between the two allopatric populations
Penry, G. S., Hammond, P. S., Cockcroft, V. G., Best, P. B., Thornton, M., & Graves, J. A. (2018) · Conservation Genetics · doi:10.1007/s10592-018-1105-4 · Cited by 22 · see citing works
Population distribution shifts of Magellanic Penguins in northern Patagonia, Argentina: Implications for conservation and management strategies
Borboroglu, P. G., Pozzi, L. M., Parma, A. M., Dell’Arciprete, P., & Yorio, P. (2022) · Ocean & Coastal Management · doi:10.1016/j.ocecoaman.2022.106259 · Cited by 22 · see citing works
Establishment of baseline haematology and biochemistry parameters in wild adult African penguins (Spheniscus demersus)
Parsons, N. J., Schaefer, A. M., van der Spuy, S., & Gous, T. A. (2015) · Journal of the South African Veterinary Association · doi:10.4102/jsava.v86i1.1198 · Cited by 22 · see citing works
Female-biased mortality in African penguins
Pichegru, L., & Parsons, N. (2014) · African Journal of Marine Science · doi:10.2989/1814232x.2014.920728 · Cited by 21 · see citing works
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Congruent, decreasing trends of gentoo penguins and Crozet shags at sub-Antarctic Marion Island suggest food limitation through common environmental forcing
Crawford, R., Dyer, B., Upfold, L., & Makhado, A. (2014) · African Journal of Marine Science · doi:10.2989/1814232x.2014.926293 · Cited by 20 · see citing works
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The initial journey of an endangered penguin: implications for seabird conservation
Sherley, R., Ludynia, K., Lamont, T., Roux, J., Crawford, R., & Underhill, L. (2013) · Endangered Species Research · doi:10.3354/esr00510 · Cited by 20 · see citing works
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Reappraisal of the Trophic Ecology of One of the World’s Most Threatened Spheniscids, the African Penguin
Connan, M., Hofmeyr, G. J. G., & Pistorius, P. A. (2016) · PLoS ONE · doi:10.1371/journal.pone.0159402 · Cited by 20 · see citing works
Cape cormorants decrease, move east and adapt foraging strategies following eastward displacement of their main prey
Crawford, R., Randall, R., Cook, T. R., Ryan, P. G., Dyer, B., Fox, R., Geldenhuys, D., Huisamen, J., McGeorge, C., Smith, M., et al. (2016) · African Journal of Marine Science · doi:10.2989/1814232x.2016.1202861 · Cited by 20 · see citing works
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Seabird‐induced natural mortality of forage fish varies with fish abundance: Evidence from five ecosystems
Saraux, C., Sydeman, W. J., Piatt, J. F., Anker‐Nilssen, T., Hentati‐Sundberg, J., Bertrand, S., Cury, P. M., Furness, R. W., Mills, J. A., Österblom, H., et al. (2020) · Fish and Fisheries · doi:10.1111/faf.12517 · Cited by 20 · see citing works
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Recent Trends of the Kelp Gull (Larus dominicanus) in South Africa
Whittington, P. A., ford, R. J. M. C., Martin, A., Randall, R. M., Brown, M., Ryan, P. G., Dyer, B. M., Harrison, K. H. B., Huisamen, J., Makhado, A. B., et al. (2016) · Waterbirds · doi:10.1675/063.039.sp102 · Cited by 20 · see citing works
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Identification of land predators of African Penguins Spheniscus demersus through post-mortem examination
Vanstreels, R. E. T., Parsons, N. J., McGeorge, C., Hurtado, R., Ludynia, K., Waller, L. J., Ruthenberg, M., Purves, A., Pichegru, L., & Pistorius, P. A. (2019) · Ostrich · doi:10.2989/00306525.2019.1697971 · Cited by 19 · see citing works
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Social context and prey composition are associated with calling behaviour in a diving seabird
McInnes, A., Thiebault, A., Cloete, T., Pichegru, L., Aubin, T., McGeorge, C., & Pistorius, P. A. (2019) · Ibis · doi:10.1111/ibi.12806 · Cited by 19 · see citing works
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Success comes with consistency in hard times: foraging repeatability relates to sex and breeding output in African penguins
Traisnel, G., & Pichegru, L. (2018) · Marine Ecology Progress Series · doi:10.3354/meps12827 · Cited by 18 · see citing works
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Growth and decline of a penguin colony and the influence on nesting density and reproductive success
Sherley, R. B., Barham, P., Barham, B. J., Crawford, R. J. M., Dyer, B. M., Leshoro, T. M., Makhado, A. B., Upfold, L., & Underhill, L. G. (2013) · Population Ecology · doi:10.1007/s10144-013-0394-1 · Cited by 18 · see citing works
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A condition index for African penguin Spheniscus demersus chicks
Lubbe, A., Underhill, L. G., Waller, L., & Veen, J. (2014) · African Journal of Marine Science · doi:10.2989/1814232x.2014.915232 · Cited by 18 · see citing works
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Processes influencing the population dynamics and conservation of African penguins on Dyer Island, South Africa
Ludynia, 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
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Combining a geographic information system, known dietary, foraging and habitat preferences, and stable isotope analysis to infer the diet of Magellanic Penguins in their austral distribution
Ciancio, J. E., Botto, F., & Frere, E. (2015) · Emu - Austral Ornithology · doi:10.1071/mu14032 · Cited by 17 · see citing works
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Authors: Crawford, R., Altwegg, R., Barham, B., Barham, P., Durant, J., Dyer, B., Geldenhuys, D., Makhado, A., Pichegru, L., Ryan, P., Underhill, L., Upfold, L., Visagie, J., Waller, L., & Whittington, P.
Affiliations: University of Cape Town (ZA)
Government of South Africa (ZA)
CapeNature (ZA)
Nelson Mandela University (ZA)
ORCID: Crawford, RJM
Altwegg, R
Makhado, AB
Pichegru, L
Venue: African Journal of Marine Science
Publisher: National Inquiry Services Center (NISC)
Published: 2011-04
Volume: 33
Issue: 1
Pages: 139-156
ISSN: 1814-232X (ISSN-L)
1814-2338
DOI: 10.2989/1814232x.2011.572377
OpenAlex: W2151041209
Cited by: 165
References: 78
Citations by year: 2026: 6 · 2025: 5 · 2024: 6 · 2023: 9 · 2022: 11 · 2021: 5 · 2020: 11 · 2019: 17 · 2018: 13 · 2017: 11 · 2016: 14 · 2015: 14 · 2014: 18 · 2013: 10 · 2012: 12
FWCI: 12.12
Type: journal article
Language: en
Open access: closed
Locations: African Journal of Marine Science (publishedVersion)
Nelson Mandela University Research Repository (submittedVersion)
Explore Bristol Research (submittedVersion)
Bristol Research (University of Bristol) (submittedVersion)
Funders: Earthwatch Institute
South African National Parks
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, population decline (ecology), breeding population, threatened species, anchovy, sardine, adult survival, purse seine fishing, Western Cape, Algoa Bay, Dassen Island, Robben Island, bycatch

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Collapse of South Africa's penguins in the early 21st century

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