Salmon is called the king of the fishes. It's been told that the scientific name is given by Julius
Caesar, who heard womthing about a fish which had the ability of jumpping up rapids.
That's why he named the fish Salmo (the jumper).
The salmon has always had a great influence on Finland. Once salmon was a part of everyday
meal during spawning time but nowdays the position of sport fishing
is very strong. Sport fishing of salmon is popular because it gives you a great challenge (salmon can gain
weight over 30 kg). You must not forget that there are many other salmon related species for
example trout, grayling, arctic charr, white fish, vendace, char and rainbow trout (dependent on
planting). Salmon needs cold and pure water with high oxygen level. Unfortunately rivers, containing pure water are getting rare. Finnish rivers which
flow to the Arctic Ocean like Teno and Näätämö contain only the original salmon population
but in southern Finland from the rivers which flow to Baltic Sea only Torniojoki and Simojoki still contain the original
population. So only two over 30 salmon containing rivers of Southern Finland still exists.
For example our research river Vantaanjoki (the River Vantaa) was an important salmon river. The destruction
began already in late 19th centuries when the clearing of log rivers began. The disaster was finished between 1940ies and 1950ies when many of the rivers were dammed because of the growning need of electicity. The fatal error of damning
became clear later. The salmon population of the Baltic Sea has also been bothered by the M74-syndrome. The M74-syndrome
is caused by retardet growth of nutritious fishes of salmon like sprat and baltic herring. Latest research results say that
there are more and more chlorine related compounds accumulating to nutritious fishes and in this
way the poisonous compounds enrich in salmons which are on the top of the food chain. The syndrome can be very dangerous, for example in year 1999 62% of the salmon alevins in Torniojoki died. Also
net fishing and salmon plantings are great threats. Planting can have a significant aeffect on the original salmon population.
However the greatest threat seems to be the salmon parasite (Cyrodactylus salaris). It is one
of the monogen parasites and has probably spreaded from Sweden. The parasite can kill fast large amounts of salmon. The salmon must be protected if the
original population is to be maintaned.
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