  Unshared consensus decision-making processes, in which one or a small number
of individuals make the decision for the rest of a group, are rarely
documented. However, this mechanism can be beneficial for all group members
when one individual has greater knowledge about the benefits of the decision
than other group members. Such decisions are reached during certain activity
shifts within the population of bottlenose dolphins residing in Doubtful Sound,
New Zealand. Behavioral signals are performed by one individual and seem to
precipitate shifts in the behavior of the entire group: side flops are
performed by males and initiate traveling bouts while upside-down lobtails are
performed by females and terminate traveling bouts. However, these signals are
not observed at all activity shifts. We find that while side flops were
performed by males that have greater knowledge than other male group members,
this was not the case for females performing upside-down lobtails. The reason
for this could have been that a generally high knowledge about the optimal
timing of travel terminations rendered it less important which individual
female made the decision.
