They tend to start concentrating when the molt starts. Although tagging and collaring programs have given researchers a good idea of where trumpeters spent the summer, until late last year, nobody knew much of anything about their winter whereabouts. S.C. Diebold, who got involved in the swan restoration effort in 1987 while he was bird curator at the Milwaukee County Zoo, arranged for the radio telemetry collars that were placed on 10 representative birds last fall during the molting season. We now know exactly where the birds were stopping along the way. Our hope is that we can apply what we learned to protecting the birds along the flyway.
Protection is necessary.
The fatal lead poisoning of swan T09 was the result of the bird's swallowing a fishing sinker he picked up in northern Illinois. Learning where the swans go for the winter and where they stop along the way can help human conservationists decide where to focus their cleanup efforts, Diebold explained. If all goes well, by next spring researchers will have a better idea of whether four short-distance migrations constituted a natural variation on swan behavior or a fluke due to the season's relatively warm weather. The project, in which 10 of the big white birds were collared with tiny radio transmitters last August, will be repeated for half that number of birds this year, and for five more birds next year. Funding for that amount of research already has been approved.