All individuals show behavioural traits that are consistent over time, but differ across individuals, and affect the expression of behaviours in different situations (personality traits). This personality traits have been shown to have consistent ecological and evolutionary consequences thus, studying the variation in personality traits is important. The aim of this thesis was to identify the variation in exploratory behaviour in red knots, understand the origin of this variation, understand how variation in exploration maintained in natural populations, and whether exploration measured in experimental setups could be extrapolated to ecological contexts. We found that experience during ontogeny (i.e., exposure to a certain physical or socia...