Perch is the most common fish in Finland. This commonly green black-striped fish with red abdominal fins on and large back fin with sharp spiny rays lives in shoals. Only in highest fell-areas in Kilpisjärvi and Enontekiö is waters in which perch don't exist.
Perch's success is based on it's low demands of environmental factors compared to salmon-species. Highly efficient spawning and versatile use of nutriments are also factors which make perch superior to many other species.
Perch tolerates higher temperatures better than Finnish salmon-species. It's demand of oxygen is only medium. Tolerance of entrophication is good until oxygen levels drop under 3,5 mg/l. At that point roach starts overrun. Perch can live also in comparitively acidic waters. Adults can manage themselves even in pH 3,5, but spawning is disturbed yet under pH 5. When pH drops near 4 perch can't breed.
Like said, perch is very versatile eater. It usually starts with plankton and when reaches 10 cm length moves on to bottom-fauna. When surrounding is ideal perch slowly then alters to fish. It is still highly adaptive, so it survives in many different waters and circumstances.
Perch is not exceedingly regional fish. Especially in larger lakes it moves in spring from deeper winter territories to shores to spawn. It spends summer in more shallow waters compared to winter. Fish is still so common that it can be reached almost anywhere.
Perch has a noticeable daily schelude that indicates it is active in mornings and evenings during summer. A gap between these activity periods is going to shorten towards autumn. At winter perch has only one period of activity in middle of the day.
Perch lies alone on the bottom in nights. By morning they school. Perch catches it's prey by chasing.
Perch breeds at May when waters have heated to 6-8 C. Copulation takes place in 0,5 - 3 m deep shores. At the bottom is good to be aquatic flora and sunken trees etc. for spawn to get stuck at. Perch spawn is covered with sheltering slime which is told to be poisonous to spawn-eaters. Female fish stays a while in breeding area in guard of spawn.
On seashores and big lakes spawning last notably long period, even four weeks. So old Finnish saying is that also slower men catch breeding perch and women to marry. Spawn is dropped in size-order: smaller first and later bigger fish in deeper water. In small lakes and ponds spawning is however past in just couple of days.
2006 Finnish pro fishermen got 1200 tonnes perch, 900 tn of that from the sea. Finnish game and fisheries research institute is somehow also calculated perch catch of recreational fishing and become in result of 13000 tn.
There is a brand new fish records for millennium in Finland. New Finnish record of perch is ice-fished 2,47 kg fish. In old record book were haunting 3,6 kg perch from 1941 that probably was only a tale.
Finns are eager ice-fishers and many tries to catch some big perchs from sunny spring ices. Perch is quite easy catch to be ice-fished. In ice-fishing contests catches commonly reach 10 kg per person. During spawntime in spring it is very easy to catch large amounts of perch also by using Finnish fish traps.
Perch is easily one of the most delicious fishes in Finland but small size annoy food usage.
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