Round goby – Neogobius melanostomus

The round goby is a bottom-dwelling fish that does not have a swim bladder and which is active when the light is low, and at night. It lives mostly in shallow water, where reproduction takes place during the summer months. Females lay their oval eggs in clusters in rock crevices. Once the male has fertilised the eggs, he stays to guard them. Round goby tolerates poor water quality, with oil present and in oxygen-poor conditions. For the winter, it finds waters that are slightly deeper.