The Deipnosophists (1.22)

Now Homer represents the men of his time as eating fish and birds: at all events, in Sicily the companions of Ulysses catch

All fish and birds, and all that come to hand

With barbed hooks.[*]

But as the hooks were not forged in Sicily, but were brought by them in their vessel; it is plain that they were fond of and skilful in catching fish. And again, the poet compares the companions of Ulysses, who were seized by Sylla, to fish caught with a long rod and thrown out of doors; and he speaks more accurately concerning this act than those who have written poems or treatises professedly on the subject. I refer to Cæcilius of Argos, and Numenius of Heraclea, and Pancrates the Arcadian, and Posidonius the Corinthian, and Oppianus the Cilician, who lived a short time ago; for we know of all those men as writers of heroic poems about fishing. And of prose essayists on the subject we have Seleucus of Tarsus, and Leonidas of Byzantium, and Agathocles of Atracia. But he never expressly mentions such food at his banquets, just as he also forbears to speak f the meat of young animals, as such food was hardly considered suitable to the dignity of heroes of reputation. However, they did eat not only fish, but oysters; though this sort of food is neither very wholesome nor very nice, but the oysters lie at the bottom of the sea, and one cannot get at them by any other means, except by diving to the bottom.

An active man is he, and dives with ease;[*]

as he says of a man who could have collected enough to satisfy many men, while hunting for oysters.