Naïve young Homing pigeons (Columba livia) learn efficient routes home but are not tied to those routes.

Understanding how animals learn about and memorize spatial information for efficient navigation, i.e. spatial memory, has been a key question within animal cognition. Homing pigeons (Columbia livia) represent a rare opportunity to study spatial memory and learned navigational behaviour in the field by conducting homing experiments in the familiar area. Evidence suggests that when pigeons are released multiple times from the same site, the birds' routes gradually become more efficient, and show idiosyncratic routes more similar to their own than other birds. This is consistent with a piloting strategy, ie. following a series of landmarks. Alongside this, they may be attracted back towards these previously learned routes when released a short distance off the original release site, despite a reduction in route efficiency. A recent experiment suggested that some aspects of this behaviour vary with age and/or experience, with birds that were one year old not showing idiosyncratic routes. In the present study, we further explore the effect of age by repeatedly training a group of juvenile birds, less than one year old, from a single release site and then subsequently testing their response to off route releases. While the birds' navigation efficiency increased significantly from their first training release to the 18^th training release, they did not show route idiosyncrasy and the difference between displacement routes suggested exploration rather than the paralleling or recapitulating observed in older birds. Our results suggest that there may be age or experience dependent variation in the use of familiar landmarks in homing pigeons.