Round goby includes mollusks, crustaceans, worms, fish eggs, zebra mussels, small fish, and insect larvae. Adult round gobies feed mainly on mollusks and other small invertebrates (insects and amphipods) living on the bottom of lakes and streams. At spring, the main items in its diet in the Sasyk Lagoon are "Hydrobia", "Cerastoderma", "Abra". In the same season near the Romanian coasts of the Black Sea the round goby feeds on polychaetes, crustaceans ("Idotea balthica", "Pachygrapsus marmoratus", "Xantho poressa", etc.) and juvenile gobies. Near Sevastopol the round goby feeds on molluscs ("Mytilaster lineatus", "Abra" spp.), but near Karadag except molluscs ("Cerastoderma", "Brachiodontes") were
Bucchich's goby algae. This species can reach a total length of up to . Bucchich's goby Bucchich's goby ("Gobius bucchichi") is a species of goby native to the Eastern Mediterranean Sea and perhaps the Black Sea. It has traditionally been considered to be more widespread, but in 2016 the similar incognito goby ("G. incognitus") was described. It had been confused with the Bucchich's goby and much information formerly published for this species is now considered to actually be for the incognito goby. The Bucchich's goby prefers coastal waters with a sandy or muddy substrate with seagrass patches or tide pools at depths