Perch

Also known as: redfin or European perch.

Names in dialect: persec, pess persec, persego.

Perch are a greenish yellow with a number of vertical bars on their sides and a protrusion on the back, which becomes more prominent with age. The anterior of the two dorsal fins is larger and features strong, sharply pointed rays (which sometimes prick inexperienced fishermen) and a dark area around the last three rays. The ventral fins are positioned forward and are yellow to orange in colour, as are the anal and caudal fins. Perch can exceed 40 cm in length and 2 kg in weight, but the most frequent sizes in the lakes in Trentino are around 15 - 20 cm.
Perch live in almost all the lakes in the Province below 1000 metres a.s.l., in the Adige, in the lower reaches of the Noce and in the Caldaro drainage canal. They prefer waters containing plenty of dissolved oxygen and vegetation. They are mainly predatory. In lakes they stay near the surface in summer to prey on bleak; during the winter they go down deep into the water. They tend to be gregarious, especially when young. They also show a certain tendency to be vagrant (eg. juveniles sporadically migrate from Lake Serraia into Rio Silla).
Perch spawn from April to June: each female lays tens of thousands of small eggs on the vegetation near the banks joined together in long gelatinous ribbons. The fry are born 15 – 20 days later. Perch populations may fluctuate considerably in numbers from generation to generation and, so the speed at which individuals grow also differs.
Perch were introduced into the lakes in Trentino in the first half of last century by professional fishermen and are also appreciated by amateur fishermen. They are also easy to propagate as the eggs can easily be recovered. When spawning begins, the fishing guards immerse bundles of wood into the water near the lakeshores onto which the fish deposit their ribbons of eggs, which can be collected and moved elsewhere. Perch have delicate, flavoursome meat, which is highly sought after; it used to be cut locally into fillets (eg. Lake Caldonazzo).