BIOENERGETICS OF AN INTERTIDAL GOBY Bathygobius ramosus

In the intertidal fish Bathygobius ramosus, larger males are more likely to reproduce than smaller ones due to male-male interactions and female preferences. Additionally, larger males are favored in foraging via intra-specific and inter-specific competition. Activity performance is also an important function associated with the ability to perform courtship, male-male interactions, and parental care. Thus, both size and activity are important components of male fitness. However, there is a direct trade-off between both functions, since the energy allocated to growth can not be allocated to behave and vice versa. This study is concerned with a trade-off between the energy devoted to growth and activity.