Banding hurts penguins' chances in wild
Scientists urged to take extra care banding, studying wildlife
By Marsha Walton
(CNN) -- Identification bands that scientists use to track and study penguins may hurt their chances of reproducing, according to new research.
The survey, involving king penguins, the second largest species of the flightless bird, found that individuals with flipper bands were less likely to breed and produced fewer offspring than those without bands.
Scientists say there's a slight increase in oxygen consumption while the banded birds are swimming, and that can make a difference when these birds travel thousands of miles foraging for food.
"Birds with the bands spend more time at sea, and less time in the breeding colony," said Dr. Yvon Le Maho from the Center for Ecology and Energetic Physiology in Strasbourg, France. "The drag effect due to the flipper band also has an effect on their ability to forage."
Some of the banded birds arrived at the breeding grounds up to three weeks after the unbanded animals, he said.
In response to the study on Possession Island in the southern Indian Ocean, several scientists agreed that it is critical for all field researchers to make sure their tagging methods are safe, effective and cause no harm to wildlife. But they also say this one study of 100 birds should not lead to any sort of widespread ban on tagging animals.
"All bands are not created equal," said Dee Boersma, biology professor at the University of Washington in Seattle. "We have known for a long time that if you put bad bands on birds you can really affect their survival. Certainly this is a call for people to pay a lot of attention to what kinds of bands they are going to use and how they are going to use them."
Boersma has studied penguin populations for more than two decades. She and her colleagues use a type of stainless steel flipper band that she says is almost a custom fit for each bird, designed to cause the least amount of interference in the bird's movements.
Both Boersma and biologist James Cahill from the University of Alberta say in the short term scientists should take another look at the specific tags used in this study in the Crozet Archipelago, about 660 miles from the coast of Antarctica.
And in the long term, said Cahill, all wildlife researchers need to question methods and equipment even if they have been using them successfully for many years.
King penguins at their breeding grounds in the southern Indian Ocean.
"Once people realized they could tag and they could follow organisms it just became a standard method. And once anything becomes standard, people sort of forget that it is an invasive treatment and it might have implications on the animals being tagged," said Cahill.
It's not just wild animals; even scientists who study plants need to be aware that their work has an impact, said Cahill.
"What we found is that simply tagging a plant and measuring it weekly, over the course of a growing season, has a profound implication on the size of the plant," said Cahill. "At the end, they tend to be smaller."
If something humans do has an impact on the wildlife they are studying, any results from those studies could be flawed.
Better, and smaller technology is helping identification become less intrusive for studying wildlife. Satellite and GPS, or global positioning system locaters, have replaced bulkier radio transmitters.
"Ten years ago we couldn't follow penguins at sea," said Boersma. "Now we can use small satellite tags and be able to learn where those birds are going to forage. It's telling us a tremendous amount about how we need to worry about the conflicts between people and penguins."
The king penguin study was published by The Royal Society, an independent scientific academy of the United Kingdom.