Spectral sensitivity in Talitrus saltator (Montagu, 1808) was investigated with classical electroretinographic techniques and behaviourally with a choice experiment. Both tests demonstrated a high sensitivity for blue light of wavelength around 450 nm, the main component of solar illumination over the sea. This maximum sensitivity could be used to guide T. saltator towards the sea to keep it within its preferred habitat on the wet zone of the beach. Colour discrimination capability was investigated by comparing the electroretinograms obtained in different conditions of adaptation (dark, blue and yellow light) and the behavioural responses to lights of different colour and varying intensities. The results of these tests suggest that, besides higher sensitivity, a specific chromatic preference for blue light could also improve seawards orientation.In its general features, the vision of T. saltator appears to be adapted for a sub‐aerial style of life on the seashore.