Domestication in fish selection increases vulnerability to angling. Two common garden‐reared genotypes of common carp, Cyprinus carpio L., differing in degree of domestication (highly domesticated mirror carp and less domesticated scaled carp) were exposed to fishing in two environments (i.e. ponds and laboratory tanks) to quantify vulnerability to angling. Foraging behaviour and food preferences were quantified to explain variation in angling vulnerability in a mechanistic manner. Domesticated mirror carp were more vulnerable to angling gear than scaled carp in both environments, which was related to greater food intake and bolder‐foraging behaviour. Independent of genotype, catchability decreased and time until first capture increased over fishing time, indicating learned hook avoidance. No differences were observed in food preferences among genotypes, rendering bait‐selective feeding an unlikely explanation for differential vulnerability to angling. It was concluded that vulnerability to angling has a genetic basis in carp and that boldness plays a paramount role in explaining why more domesticated genotypes are more easily captured by angling.

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Fine‐scale underwater telemetry affords an unprecedented opportunity to understand how aquatic animals respond to environmental changes. We investigated the movement patterns of an aquatic top predator, Eurasian perch (Perca fluviatilis), using a three‐dimensional acoustic telemetry system installed in Kleiner Döllnsee (25 ha), a small, shallow, mesotrophic natural lake. Adult piscivorous perch (N = 16) were tagged and tracked in the whole lake at a minimum of 9‐s intervals over the course of one year. Perch increased swimming activity with higher water temperature and light intensity. Air pressure, wind speed and lunar phase also explained perch movements, but the effects were substantially smaller compared to temperature and light. Perch showed a strong diel pattern in activity, with farther swimming distances and larger activity spaces during the daytime, compared to the night‐time. To investigate the influence of prey distribution, we sampled the prey fish in both littoral and pelagic zones in both day and night monthly using gill nets. We found that the prey fish underwent diel horizontal migration, using the littoral zone during the day and the pelagic zone during the night. However, perch showed the opposite patterns, suggesting either that the prey fish avoided predation risk or that the horizontal diel migration of perch was driven by other mechanisms. Our results collectively suggest that the movement ecology of piscivorous perch is mainly governed by a foraging motivation as a function of abiotic variables, especially temperature and light.

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