for National Geographic News
At a glance, it is nearly impossible to identify an individual penguin in a colony of several thousand. That's a serious problem for researchers who want to identify and track individual birds as part of their efforts to protect them.
To overcome the problem, many researchers attach stainless steel identification tags to the penguins' flippers (wings), but some long-term studies suggest these tags rub at the birds' insulating feathers and slow the birds down as they swim through the water.
"There's quite a bit of controversy about it," said Peter Barham, a polymer physicist with Bristol University in the United Kingdom.
Barham, who is not a biologist by training but passionate about penguins, is designing a new identification tag made out of silicone rubber. He hopes the new tags will be less harmful to the birds.
Dee Boersma, a conservation biologist and penguin expert at the University of Washington in Seattle, said that determining whether the new silicone rubber tags are an improvement will require several years of tests.
"It's always a good idea to develop new bands, but the real question is will these new bands be better?" she said. "We won't know until someone tests them and sees."
The new tags are designed to be flexible enough to prevent wear on the birds' feathers yet fit snuggly around the wing, thus reducing any tag drag that may slow the birds as they swim.
The first generation of Barham's silicone rubber tags fit like an airfoil on the flipper but proved too cumbersome when tested on wild penguins in South Africa. A second-generation prototype, designed more like a ring, is currently being developed.
Preliminary results from tests of the new prototype on captive penguins suggest an improvement over conventional stainless steel tags. She says but "whether it will work in practice has yet to be seen," Barham said.
Boersma is currently preparing a manuscript describing results from a ten-year study on a variety of tagging techniques, researchers will need at least five years of data before any conclusions can be made concerning the efficiency of the silicone rubber tags.
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