EARTHWATCH PROJECT
South African Penguins
Introduction
Demographic studies of birds have relied, to a large measure, on the use of rings (bands) to identify individual birds for more than a century. These studies form a key component of improving the conservation status of birds, through providing an understanding of movements and survival rates. Nowadays, the most commonly used rings are made from metal alloys and are fixed around the bird's leg. However, in the case of penguins, leg bands are impractical, so most demographic studies have used stainless steel bands fixed around the top of the flipper.
The stainless steel flipper bands, presently used to identify penguins, are difficult to read in the field. There are also suggestions that they may adversely affect some penguins, particularly through disturbing the hydrodynamic flow over the flipper when the bird is swimming. Accordingly there is a crucial need to improve ways of marking penguins. With the enormous number of new chemicals that have become available since the development of stainless steel, there is a need to search among these for a new method using modern materials technology. Dr Peter Barham, H.H. Wills Physics Laboratory, University of Bristol, England, has designed the first of these new-generation bands.
Of the world's 17 species of penguin, two species are "Endangered", seven (including the African Penguin) are "Vulnerable", and two are "Near-threatened". This alarming status of the world's penguins makes it imperative to conduct conservation-orientated research, for which suitable marking methods are essential, but not yet satisfactorily designed and field-tested.
Field tests on the new bands developed at the University of Bristol have been conducted on African Penguins Spheniscus demersus at Robben Island, off Cape Town, South Africa, since March 2001. The tests are a joint project of the Physics Department of the University of Bristol, the Avian Demography Unit of the University of Cape Town, Robben Island Museum, and Marine and Coastal Management of the South African Department of Environmental Affairs and Tourism. The project is being done in collaboration with the Earthwatch Institute.
Three groups of birds with nests are selected: unbanded pairs, unbanded pairs that are banded with rubber bands during the Earthwatch teams and pairs that have been banded previously with stainless steel flipper bands. There is a target number of 40 nests in each group for each year. These nests are monitored throughout the breeding season (March until September) by Earthwatch volunteers, South African students, and staff of the four participating organisations. The objective of the fieldwork is to test the performance of the new rubber flipper bands, and to compare the breeding productivity of birds in the three groups. Other relevant research is also conducted on the island during the Earthwatch teams.
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