Are personality traits consistent in fish?-The influence of social context

- Escape responses from a net can be used as a proxy for personality in seabream.
- Grouping individuals with similar personality results in personality changes.
- Grouping individuals with different personality suggests consistent personality traits.
- Social context influences personality traits in gilthead seabream (Sparus aurata).

Individual differences in behavioural and physiological responses to challenges are progressively accepted as adaptive variation and reveal a strong degree of evolutionary conservation throughout the vertebrate taxa. Previous studies in gilthead seabream (Sparus aurata) suggested that individual differences in behaviour reflect distinct coping styles or personality, contrasting consistent traits associations. One of the traits that have been shown to be consistent over time and across context is the escape response under a restraining test. Using this trait as a proxy of personality in seabream the influence of social context in the consistency of escape behaviour was investigated. Individually tagged juvenile seabream (n = 360; 70.18 ± 11.44 g; mean ± SD) were subjected to a restraining test that consisted of keeping each fish in an emerged net for one minute. Behaviours measured in the net (latency to escape; number of escape attempts and total time spent on escaping) were collapsed into first principal component scores using Principal Components Analysis (PCA). Using the PCA scores the individuals were distributed into homogeneous groups (n = 30 each group) of proactive, reactive and intermediate. Control groups consisted of mixed groups with 1/3 of each coping style. After one month the same individuals were exposed to the same test (restraining test) to assess consistency of behavioural responses. Results indicate that homogenous groups of proactive (p = 0.086) and reactive (p = 0.159) individuals did not exhibit consistent behavioural responses as opposed to the intermediate (p = 0.028) and control groups (p < 0.001). This study thus confirms that the social context in which fish are kept significantly influence personality traits.