 Internally, the sexes of most marine animals can be determined by looking at the gonads.For example, male testes of spawning fish are smooth and white and account for up to 12% of the mass of the fish, while female ovaries are granular and orange or yellow, accounting for up to 70% of the fish's mass.Male lampreys, hagfish and salmon discharge their sperm into the body cavity where it is expelled through pores in the abdomen.