Yesterday lunchtime, a catch of 31 was made. It may not seem many but is actually more than had previously been marked on the island. The birds were marked with individually numbered metal and plastic rings and a plastic neck-collar. Two birds were given high-tec GPS collars which record their position within 20 metres every four hours and then transmit this information via mobile phone masts and thence to the scientists' computers. If there's no phone mast within range, the data are stored until there is. The solar-powered battery in the collar should last a number of years, potentially giving a mass of detailed information on where the birds stay during the winter, their migration routes via Iceland, and their breeding grounds in western Greenland.
|A Whitefront waiting to be marked and measured.|
|Once the geese are ringed, they are placed in a small dark tent and then released in batches.|