Nonmating behavioural differences between male tactics in the invasive round goby

Alternative reproductive tactics (ARTs) exist when individuals of one sex (usually males) adopt different strategies to achieve reproductive success. Although it is well known that the males adopting the different tactics often vary in their morphological, physiological and mating-based behavioural traits, what is not well understood is whether variation also exists in their behaviour outside the mating context. Here, we used the round goby, …