Thorsen wrestles the bird into the boat and prepares to fit it with a radio collar. He wants to know if swans stay on one part of the river or whether they move around. So now what we're going to do is process and band this bird. First of all, we're going to sex it to determine whether it's a male or a female. We already know it s an adult because it's in full white plumage.
Juveniles are gray and have a pinkish bill.
So we ll sex it first, and weigh it, and take five body measurements. Yep, this is a female. Thorsen says after his initial two-year study on swan movement and population numbers, he wants to find out more about what they eat on the river. Swans are primarily aquatic foragers, especially on the river here. We think they re eating wild celery tubers and arrowhead tubers.