Does Thermal Plasticity Affect Susceptibility To Capture In Fish? Insights From A Simulated Trap And Trawl Fishery

In fishes, physiological and behavioural traits can correlate with vulnerability to capture with fishing gears, highlighting the capacity of fisheries selection to drive phenotypic change in exploited populations. There remains a paucity of information regarding how different fishing gears may select on phenotypic traits and how relationships between individual traits and capture vulnerability change across environmental gradients. By simulating the capture process in a trawl and trap using wild minnows (Phoxinus phoxinus) acclimated to different temperatures, we investigated how contrasting fishing gears select on behavioural and physiological traits and how this selection is modulated by temperature. Despite similar risk of capture in each gear, selection differed between traps and trawls. Fish exhibiting low spontaneous activity were at greater capture risk in the trawl across all temperatures, while traps showed no selection except at 24 degrees C. No relationships between physiological traits and capture vulnerability were found, except between swim performance and trap capture vulnerability at 24 degrees C. This study demonstrates that fisheries selection on individual traits is likely context-specific, depending on both fishing gear type and environment.