How did Venice control its fish-markets in the past?
A white marble plaque at the Loggia Grande at Rialto
Today It is still possible to map topologically the interior subdivision of the Rialto market just by following the remained toponyms such as the "Erbaria" for the vegetable market, the "Drapperia", for the sale of fabric and silk, the "Beccaria" for the sale of meats, the "Caseria" for cheese and the "Pescheria" for fish.
Although fish was sold in other parts of Venice, Rialto has always been the most important one, where a wide range of fish has always been sold starting from 1097.
On the wall of the Loggia Grande there is an old white plaque, which includes a list of fish names with their sizes to be followed and to be sold by the minute. The names of the species are written in Venetian dialect. For example the branzin is the sea-bass and its length was once 12 cm, today 25 cm, the peocio , mussel, from 3 cm to 5 cm.
What does this mean? With an edict from 1173 Venice decided to regulate the size of the fish that was sold in the city. Consuming fish at a young age means compromising the natural balance of the species, so in order to preserve fish reproduction. Length and seasonality became part of the same target. In case of non-observance of those rules, severe punishments were imposed.