Far From Land The Mysterious Lives of Seabirds

PLATE 3. The long- distance movements of Common Terns breeding in Germany
can be tracked by geolocators on the bird’s legs (upper), while comings and goings
at the colony are monitored by an antenna surrounding the nest that detects the
bird’s implanted PIT tag (lower). (Upper © Sabrina Weitekamp, Lower © Peter
Becker.)