JOHN YELD
Environment & Science Writer
RICHIE, Nicky and – hopefully – Lucy are still swimming along happily in the cold Benguela Current off southern Africa’s west coast, blissfully unaware that their “designer” backpacks are transmitting unique data that could prove vital to the future of their endangered species.
The trio are adolescent African Penguins, and were rescued as orphans and hand-reared at the Rietvlei headquarters of the Sanccob (Southern African Foundation for the Conservation of Coastal Birds) before being released in the sea off Cape Town at various times over the past six weeks.
Each is carrying a 30g remote-sensing satellite transmitter – known as a Platform Transmitter Terminal – that sends a highly accurate GPS reading every other day to the Argos satellite system, used by many institutions around the world, including the Oceans and Coasts branch of the national Department of Environmental Affairs.
The department is one of the partners in the collaborative “Chick Bolstering Project”, with Sanccob, the Bristol Conservation and Science Foundation in the UK, UCT’s Avian Demography Unit, CapeNature, Robben Island Museum, and International Fund for Animal Welfare.
The African Penguin, one of 19 penguin species worldwide, has experienced “a dramatic and sustained decrease” in population in the past 10 years and is now listed as “endangered” in the IUCN Red List of Threatened Species, the Avian Demography Unit says on its website.
Scientists believe one of the main reasons for this is the “mismatch” that has developed between the locations of penguin breeding colonies in the Western Cape and the availability of the sardines and anchovies on which they feed.
These fish stocks have moved significantly eastwards in recent years, and breeding penguins – which must deliver food to their chicks in the nest to ensure that they fledge successfully – cannot reach them.
To counter this, there’s an innovative proposal to start a new mainland breeding colony, possibly using hand-reared chicks, closer to the current central mass of fish.
Each year Sanccob rears hundreds of orphaned chicks, most of them from colonies managed by CapeNature where the youngsters have been abandoned by their moulting parents at the end of the breeding season.
But scientists know little about the period in the life of adolescent penguins between when they fledge until they return to colonies to breed, when they are about three to four years old.
The satellite transmitters fitted to five young birds – Lucy, Richie and Nicky are the first three – will help scientists understand what drives penguin fledglings to return to the colonies where they were hatched, or to disperse to other sites as breeding adults, the Avian Demography Unit’s Dr Richard Sherley, who is heading the research component of the project, says on the website.
Lucy, the first, was released on June 26 and just 19 days later had swum well over 700km to a position 20 nautical miles south-west of Possession Island, about 40km south of Lüderitz in Namibia. However, there have been no signals from her transmitter since Saturday, July 23, Sherley reports.
“Given that Lucy was still moving long distances up to the last update we received, it’s most likely that the (transmitter) has fallen off or failed earlier than expected.”
Richie, released in Table Bay on July 19, was about 40km north-west of Port Nolloth and 60km short of Alexander Bay and the Orange River mouth on Monday. Also on Monday, Nicky, who was released on July 26, was just over the border between the Western and Northern Capes and about 10km offshore and 35km north-west of the Olifants River mouth.
l Read the full story at http://penguins.adu.org.za