A GPS logger and software for analysis of homing in pigeons and small mammals

A detailed analysis of homing in pigeons and small mammals has remained dif ficult because the paths of the animals could not be reconstructed precisel y. Here, we describe a lightweight global position system (GPS) data logger (35 g including battery and casing; 40 x 68 x Is mm) that records the flig ht of pigeons and the path of dogs with an accuracy of +/- 12 m. With one b attery, the logger runs in continuous mode (1 fu's) for 3.5 h and in power- saving mode (1 fix/5 s) for about 16 h, and stores a maximum of 100,000 dat a points that an downloaded to a PC. A module of our public domain software WINTRACK permits a detailed numerical and graphical analysis of path geome try, phases of resting and moving, and path similarity. The device can be a dapted to different species provided that satellite signals can be received reliably and that the loggers can be recovered. We expect it to be useful for testing hypotheses about pigeon homing, assessing natural spatial behav ior and orientation of many species, and anticipate further miniaturization . (C) 2000 Elsevier Science Inc. All rights reserved.