Effects of Catch-and-Release on Feeding Responses and Aggressive Behavior in Nile Tilapia - Dataset
Description of this data
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.
Experiment data files
Steps to reproduce
To assess whether feeding responses and agonistic interactions would be altered in fish before and after catch and release, 30 individuals of Nile tilapia were distributed equally (N = 10) between three treatments (control, chase/capture (C&C) and catch/release (C&R)). Fish were individualized in glass aquaria (40 x 24 x 23 cm), and they were allowed to acclimate for 3 days in this condition. After this period, the feeding responses and agonistic behavior (through mirror test) were evaluated once every day for 2 days to assess their initial/basal feeding responses and aggressive behavior. Thereafter, on the third day (see details below), the fish were exposed to either angling or chasing/capturing procedures (see details below) or no-handling (control). The fish had their feeding responses evaluated 2, 24 and 48 hours post-handling, and aggressive behavior was evaluated 2, 6, 24 and 48 hours post-handling. The chased and captured treatment was important (positive control) to appropriately assess the angling/hook effect, i.e., do the hook and unhook procedure affect the feeding responses and behavior? To what extent is the angling and especially the hook responsible for the changes, or only the fact the fish is chasing and air exposure cause most of the impact?
The differences between the treatments were examined using linear mixed-effect models by applying the lmer function implemented in the lme4 and lmerTest packages of R and the Akaike criterion. We set
treatment´ and ‘sampling’ as fixed factors, whilefish´ was included as a nested random term to account for their variation. We tested assumptions through a Kolmogorov-Smirnov test for normality and a Levene test for homoscedasticity. Post-hoc comparisons were performed using a Tukey HSD test. Data were log-transformed for latency for the first aggressive behavior and the number of bites to arrive at the assumptions.
Cite this dataset
Camargo dos Santos, Bruno; Stramantinoli Rossi, Vanessa; Bastos Gonçalves, Bruno; S. Zanuzzo, Fábio; Leutz, Juliane; Cardoso Giaquinto, Percília (2020), “Effects of Catch-and-Release on Feeding Responses and Aggressive Behavior in Nile Tilapia - Dataset”, Mendeley Data, v1 http://dx.doi.org/10.17632/9d2jhscwm4.1
The files associated with this dataset are licensed under a Creative Commons Attribution 4.0 International licence.