The impact of tag position and mass on motor behavior in pigeons

Abstract

Tags, such as GPS tags and satellite tags, are widely used in wildlife research as a useful tool for observing behavioral ecology. Here, we investigated the impact of tag position and mass on the motor behavior of pigeons (Columba livia domestica). We used sandbags sized 4 × 4 cm2 to simulate load and assess load capacity. The results showed that the tag had the least impact on the pigeons when attached to the middle of the synsacrum: the change rate of height (CRH) was − 4.48%, the change rate of tail angle (TA) was 14.61%, the change rate of tarsometatarsal angle (TMA) was 17.90%, and the change rate of activity level (AL) was 85.96%. The tag mass ≤ 30 g (6.0% of body mass) had relatively little impact on pigeons: CRH was ≤ 7.0%, TA was ≤ 22.51%, TMA was ≤ 5.28%, and AL was ≥ 82.95%. We then tested the impact of the tag mass at its optimum location on the motor behavior of the birds. With increase in the tag mass, the step length became longer and the time of passing through the labyrinth decreased. With the tag mass of 30 g, the pigeons could easily fly out of the arena during initial flight. In conclusion, the optimal position of the tag was in the middle of the synsacrum, and the tag mass of ≤ 6.0% of the body mass had the least impact on pigeons. Thus, tag mass should be much less than 6.0% of the body mass in application for pigeons.