Effects of catch-and-release on the behavior and catchability of a Neotropical fish species

The effectiveness of catch and release (CR) is characterized by the survival and welfare of fish after their release, as long as they are managed appropriately. It is also a strategy used to ensure the preservation of fish species. Thus, the hypothesis that continuous CR is not a stressor that affects the welfare and behavior of the exploited population was tested. For this purpose, an experiment was carried out with four tanks subjected to CR fisheries management and four control tanks (C) without any fishing activity. Mortality, capture rate, immediate bait predation response, and cortisol and glucose stress indicators in Astyanax lacustris were evaluated. No death occurred in both groups during the experiment, and levels of cortisol and glucose levels did not differ between the CR and C groups. However, there was a reduction in the capture rate and changes in bait predation behavior over time in CR. Despite the observed change in behavior, CR did not prove to be a stimulus capable of causing stress in the A. lacustris Fish populations can recognize baits as threats and, thus, after experiencing catch and release, they start avoiding them.