Effects of Catch-and-Release on Feeding Responses and Aggressive Behavior in Nile Tilapia - Dataset

In the present paper, we assess whether fish feeding responses and aggressive behavior can be affected by a hook injury (C&R). We assessed this question using an aggressive cichlid fish species, the Nile tilapia (Oreochromis niloticus), which displays pronounced dominance hierarchies and is a territorialist species. Hierarchy and territorialism are dependent of aggressivity and the nutritional state of individuals and thus may be affected by C&R. We exposed fish to three treatments: control (no-handling), chase/capture (C&C) and catch/release (C&R). Fish had their feeding responses (latency to feed and time to eat all feed pellets) evaluated prior to and at 2, 24 and 48 h post-handling, and the aggressive behavior was evaluated prior to and at 2, 6, 24 and 48 h post-handling. The aggressive behavior (latency, number of bites and confront index) was evaluated through the mirror test. We observed that 2 h after the catch-and-release, fish took a longer time to eat all pellets. In general, control fish displayed a consistent increase in aggressive behavior over time, and this pattern was interrupted by C&C, and an even larger response was seen in fish exposed to C&R, which had a consistent reduction in the number of bites post-handling compared to other groups. Although fish showed a tendency to become less aggressive post-C&R handling, catch-and-release did not largely affect their feeding responses or aggressive behavior, demonstrating that Nile tilapia is resistant/resilient to physical handling such as C&C or C&R.