Reproductive priming in mature male Atlantic salmon parr exposed to the sound of redd cutting

The sounds of a wild female Atlantic salmon cutting a redd were associated with significant increases in the levels of plasma 17,20β‐dihydroxy‐4‐pregnen‐3‐one (17,20βP) and of expressible milt in mature male parr, comparable with levels of the steroid and milt produced in parr exposed to the priming pheromone, prostaglandin F2a. Hence auditory cues may have a significant role in synchronising reproductive physiology in Atlantic salmon.