From local collective behavior to global migratory patterns in white storks

Successful bird migration can depend on individual learning, social learning, and innate navigation programs. Using 8 years of data on migrating whooping cranes, we were able to partition genetic and socially learned aspects of migration. Specifically, we analyzed data from a reintroduced population wherein all birds were captive bred and artificially trained by ultralight aircraft on their first lifetime migration. For subsequent migrations, in which birds fly individually or in groups but without ultralight escort, we found evidence of long-term social learning, but no effect of genetic relatedness on migratory performance. Social learning from older birds reduced deviations from a straight-line path, with 7 years of experience yielding a 38% improvement in migratory accuracy.

Research into the puzzling phenomena of animal navigation and aggregation has proceeded along two distinct lines. Study of navigation generally focuses on the orientation ability of the individual without reference to the implications of group membership. A simple principle (the 'many wrongs principle'), first proposed by Bergman and Donner in 1964, and developed by both Hamilton and Wallraff three decades ago, provides a link between these lines of current interest by suggesting that navigational accuracy increases with group size. With unprecedented scope for testing the hypotheses it generates, it is now time that the many wrongs principle is exhumed.