Abstract
Light can be used to deter bycatch from fishing nets, but few studies have aimed to quantify how species view and respond to light. Here, we used visual models to predict how target (plaice Pleuronectes platessa ) and bycatch (small‐spotted catshark Scyliorhinus canicula r and undersized skates, Raja spp ) species, captured in mixed demersal fisheries, responded to light‐emitting diodes (LEDs) in tanks. Models predicted that behavioural responses were linked to the likely visibility of LEDs to catsharks. Specifically, catsharks interacted more with LEDs that were apparently more stimulating to their vision (white, green, blue). In contrast, skates and plaice were less responsive to light. Potential responses of species to light could be inferred from visual models, but differences in ecology translated into differences in behaviour towards light. Our modelling approach could help to select an optimal light colour for future bycatch‐reduction trials.