Action: Artificially incubate and hand-rear penguins in captivity
Two replicated and controlled studies from South Africa found that hand-reared and released African penguins Spheniscus demersus had similar survival and breeding success as birds which were not orphaned and hand-reared.
Artificial incubation involves removing eggs from incubating parents and using an incubator to hatch them. Techniques can be extremely complex, with precision humidity and temperature control and turning of the eggs to ensure correct development Hand-rearing can be used with chicks from artificially-incubated eggs or with chicks removed from parents after hatching and involves manually feeding chicks until independence. Both techniques can be used to encourage parents to produce more offspring, or when naturally-raised chicks and eggs have low survival.
Supporting evidence from individual studies
A replicated study in the Western Cape, South Africa, in 1994-9 (Whittington 2003), found that orphaned African penguins Spheniscus demersus that were hand-reared and released had similar survival and breeding probabilities as naturally-fledged chicks (11% of 437 hand-reared chicks seen at colonies, 1% breeding, 2% found dead vs. 9%, 1% and 1% of 399 naturally-fledged chicks). Of 507 chicks that were hand-reared, 437 (86%) were successfully released into the wild. Survival of rehabilitated adults is discussed in ‘Clean birds following oil spills’ in ‘Threat: Pollution’.
A controlled and replicated study on Robben and Dassen Islands, South Africa (Barham et al. 2008), found that the survival to breeding age and breeding success of African penguins Spheniscus demersus during 2001-6 were similar for birds that were orphaned in the Treasure oil spill in 2000 and hand-reared, compared to birds that were not orphaned and hand-reared (1.6 chicks fledged/pair for 24 pairs with at least one hand-reared bird vs. 1.1 chicks fledged/pair for 227 pairs without hand-reared birds). The authors note that the sample size of hand-reared pairs was too small for statistical tests to determine significance.
- Whittington P.A. (2003) Post-release survival of rehabilitated African penguins. Pages 8-17 in: D.C. Nel & P.A. Whittington (eds.) Rehabilitation of oiled African Penguins: a conservation success story. Birdlife South Africa and Avian Demography Unit, Cape Town.
- Barham P.J., Underhill L.G., Crawford R.J.M., Altwegg R., Leshoro T.M., Bolton D.A., Dyer B.M. & Upfold L. (2008) The efficacy of hand-rearing penguin chicks: evidence from African penguins (Spheniscus demersus) orphaned in the Treasure oil spill in 2000. Bird Conservation International, 18, 144-152