Hand-Rearing, Release and Survival of African Penguin Chicks Abandoned Before Independence by Moulting Parents

Abstract

The African penguin Spheniscus demersus has an ‘Endangered’ conservation status and a decreasing population. Following abandonment, 841 African penguin chicks in 2006 and 481 in 2007 were admitted to SANCCOB (Southern African Foundation for the Conservation of Coastal Birds) for hand-rearing from colonies in the Western Cape, South Africa, after large numbers of breeding adults commenced moult with chicks still in the nest. Of those admitted, 91% and 73% respectively were released into the wild. There were veterinary concerns about avian malaria, airsacculitis and pneumonia, feather-loss and pododermatitis (bumblefoot). Post-release juvenile (0.32, s.e. = 0.08) and adult (0.76, s.e. = 0.10) survival rates were similar to African penguin chicks reared after oil spills and to recent survival rates recorded for naturally-reared birds. By December 2012, 12 birds had bred, six at their colony of origin, and the apparent recruitment rate was 0.11 (s.e. = 0.03). Hand-rearing of abandoned penguin chicks is recommended as a conservation tool to limit mortality and to bolster the population at specific colonies. The feasibility of conservation translocations for the creation of new colonies for this species using hand-reared chicks warrants investigation. Any such programme would be predicated on adequate disease surveillance programmes established to minimise the risk of disease introduction to wild birds.

Herpesvirus-like respiratory infection in African penguins Spheniscus demersus admitted to a rehabilitation centre

“…The cases were all large downy chicks or those mostly covered with fledging plumage (> 36 d old; Sherley et al 2014). Body condition of these chicks was poor (less than Mean − SD) or mediocre (within Mean ± SD) in relation to all chicks admitted to the centre during the same period.…”

“…Here we consider data from African penguins admitted to the Table View facility (33°50' 02 The following data were collected: individual number, date and location of capture, chick stage at admission on a scale from P0 (newly hatched) to P4 (close to Fledging) (Sherley et al 2014), outcome of rehabilitation (release to the wild, death, euthanasia), body mass on admission (floor-standing scale with precision ± 20 g) and head length on admission (measured with a Vernier calliper from the back of the head to the tip of the beak). A body condition index was calculated using a modified Veen index method (BCI4) that uses the head and mass measurements (Lubbe et al 2014).…”

Body condition as a quantitative tool to guide hand‐rearing decisions in an endangered seabird

“…Barham et al ., , ). More recently, many chicks have been admitted for hand‐rearing due to adult penguins entering moult with dependent chicks still in the nest, likely because of prey scarcity (Sherley et al ., ). African penguins moult their whole plumage simultaneously, so lose their waterproofing and are unable to catch food for c .…”

“…21 days (Cooper, ). Any unfledged chicks are abandoned to starve (Sherley et al ., ). Between 2001 and 2013, as few as 82 (2001) and as many as 841 (2006) such chicks have been collected annually for hand‐rearing and release back into the wild (Parsons & Underhill, ; Sherley et al ., ).…”

“…Rehabilitating abandoned chicks aims to bolster this declining population while methods are developed to establish breeding colonies where prey availability is higher (Schwitzer et al ., ). Hand‐reared chicks have similar survival and recruitment rates to wild progeny (Barham et al ., ; Sherley et al ., ). Thus, maximizing release rates could provide conservation benefit in line with the national and international recommendations to reinforce populations and establish techniques for conservation translocations (Ellis, Croxall & Cooper, ; Crawford et al ., ).…”