(4) That no citizen could be prevented from fishing in the sea and such rivers by any person. To this rule there are several exceptions; for instance, (a) a cove of the sea bordering on a man’s land—perhaps if enclosed with stakes, etc.—could be exclusively occupied for fishing (Digest, 47. 10, ss. 13 and 14); (b) a right of fishing in a recess or backwater of a public river could be acquired by prescription, and would then be protected by a possessory Interdict against any one who tried to fish this water (Ibid., 44. 3. 7).
It is hard to define precisely what constituted a public river and what a private river. Under the term “public” came all rivers of any size, not merely those that were tidal. Whether a river was public depended not only on its size, but also on the “opinion of those dwelling around it.” No river, periodically dry in summer, could be accounted public (Digest, 43. 12, ss. 1-4).
All streams not public, many lakes, and all piscinæ, etc., were private property, from which the owner could prevent any one taking fish. The legal remedy for such exclusion, based on the ground of trespass, was Interdict—a procedure very similar to that of Scotland, whose law is mainly modelled on that of Rome.
The further legal question—were the fish in such piscinæ res nullius or were they such individual property as to make any one taking them without permission liable for theft—was answered by the jurist Nerva in Digest, 41. 2. 3, s. 14, who held that they were individual property—“pisces quos in piscinas coiecerimus a nobis possideri.”
Thus the owner of vivaria could proceed against a poacher by (1) an interdict for trespass, and (2) a prosecution for theft, in case of a fish being caught with the intention of taking it away. On the other hand, a person prevented from fishing or navigating by another could only proceed by an action of Injuria, personal affront (Digest, 43. 8. 17, ss. 8 and 9; 41. 1. 30; 43. 14, s. 7).
Although I purposely limit myself to a very slight sketch of Roman regulations, the case reported by Pliny (N. H., IX. 85) seems, alike from legal and piscatorial interest, worthy of reproduction and examination.
As the Anthias is one of the shyest of fishes, special precautions and plenty of patience were necessary for a good catch. Thus fishermen wore clothes of the same colour as their boats. They sailed without fishing over the same stretch of sea. They merely went on “baiting the swim” on each tack, day after day, till some spirit, bolder than the rest, could be induced to take the bait. Still more days elapse before the fish, which has by this time been well identified, is followed by any of his mates. Eventually example proves so infectious that shoals innumerable, of which the Elder Brethren even eat from the fisherman’s hands, surround the boat.
Now is the accepted hour for “the fisherman to throw out a little beyond his finger tips a hook concealed in bait,” and (to prevent alarm) smuggle the fish out gently, one by one, by a very slight jerk. His mate receives the fish on pieces of cloth, so that no floundering about or other noise may scare their comrades. On no account must “the betrayer of the others” be captured, lest instantly the shoal take to flight and be no more seen.
But “there is a story that a fisherman, having quarrelled with his mate, threw out a hook to one of the leading fishes, which he easily spotted and with malicious intent captured. The fish was, however, recognised in the market by his mate, against whom he had conceived this malice: accordingly an action for damages (damni formulam editam) was brought, which the defendant, as Mucianus adds, was condemned to pay.”
Now, as shown above, (1) a fish is “res nullius,” (2) a fish becomes the property of him who first “reduces it into possession,” (3) the sea, with some exceptions which do not apply here, is not capable of individual ownership.