48 forms ( species and infraspecific taxa ) of fish have been encountered in the lake, including roach, carp bream, zander, European perch, ruffe, endemic variety of smelt, two varieties of Coregonus albula ( vendace ), eight varieties of Coregonus lavaretus, a number of other Salmonidae as well as, albeit rarely, endangered European sea sturgeon.

The darters, perches, and their relatives are in this family: well-known species include the walleye, ruffe, and three species of perch.

The Karelian Isthmus is a popular place for hiking, cycling, skiing ( Korobitsyno and Kavgolovo ), climbing ( near Kuznechnoye ), canoeing ( Losevo ), fishing for consumption ( of carp bream, northern pike, roach, European perch, ruffe, burbot and others ), mushroom hunting ( for porcini, red-capped scaber stalk, birch bolete, velvet bolete, slippery Jack, golden chanterelle, Lactarius resimus, woolly milk-cap, ugly milk-cap, saffron milk-cap, Lactarius rufus, various Russulas and others ), berry picking ( of bilberry, raspberry, woodland strawberry, cowberry, cranberry, cloudberry, bog bilberry and stone bramble ).

They are dominated by the genera Gobio, Romanogobio, Squalius and Chondrostoma and contain such species as carp, Prussian carp, roach, bream, Silver Bream, pike, perch, ruffe, chalcalburnus, Sprattus, Mugil and others.

Ever since the ruffe were detected, studies have not only shown that the ruffe and the yellow perch are closely related but they are quickly becoming rivals.

It shouldn't be too long for the ever so quickly reproducing ruffe to soon phase out any perch that stands in its way.

The lake contains salmon, trout, pike, perch, minnow, dace, ruffe and eel, though the predominant species is roach, which is believed to have been introduced in the form of discarded live-baits by visiting pike anglers.

Fish types include roaches, some gobies, Crucian carps, sabre carp, perch, ruffe, pike, Common dace, silver bream, ide, gudgeon, carp bream, spined loach, European smelt, char, pike-perch, rudd and burbot.

Its common names are ambiguous – " ruffe " may refer to any local member of its genus Gymnocephalus, which as a whole is natively endemic to Eurasia.

The most obvious features to recognize a ruffe are the ruffe's large, continuous dorsal fin and its slightly downturned mouth.

In Eurasia, the ruffe diet mainly consists of zoobenthos: chironomids, small aquatic bugs and larvae, which are all found in the Benthic zone of the water column.

From here, the ruffe gradually mature until they are 2 – 3 years old, when they reach full maturity.

In the beginning, the main method of control was to increase the Walleye and Northern Pike populations because they are natural predators of the ruffe.

Powan populations are relatively healthy, but may have been negatively impacted by the introduced ruffe, which eats powan eggs and fry.

It also contains the endemic gwyniad, now listed as critically endagered by the IUCN due to the introduction of the invasive and non native ruffe.

The ruffe also has a large, spiny dorsal fin likely distasteful to its predators.

The ruffe also has an excepional ability to detect water vibrations through organs called neuromasts.

Not only has the ruffe become an inconvenience but, it is also the first invasive species to have been labeled a nuisance by the Non-indigenous Aquatic Nuisance Prevention and Control Program.

also the ruffe has a spiky fin

The ruffe is usually 4-6 inches ( 10 – 15 cm ) in length and will never exceed 10 inches ( 25 cm ), but is a very aggressive fish for its size.

The primary spawning season for the ruffe occurs from the middle of April through approximately June.

Life, for the Eurasian ruffe, starts as an egg, like other fish.

Therefore, having more ruffe in the water, leads to less food for other fish.

Ever since the ruffe was introduced into the Great Lakes system, scientists and fishery managers have been searching for the right way to get rid of them.

This trait both aids the ruffe in finding food and gives the rudge an edge in avoiding predators.

Finally, the scientists found that it is resilient to freezing, so even during Minnesota's long winter season ; the ruffe could still be controlled.

At full length, the adult ruffe is usually around 20 cm, but at a maximum of 29 cm.

Growth is usually occurs more when the ruffe is in clear, brackish waters.

If there is no intervention taken by the public the ruffe have the potential to ruin Lake Superior.

If a large school of ruffe is found, they can be poisoned.

Second, the pheromone is species specific, so it would only repel the ruffe, none of the other fish.

By using this method there is a chance the ruffe could be prevented to go to their natural mating spots and therefore eventually the ruffe might die out.

The population is threatened by deteriorating water quality and by the ruffe, a fish introduced to the lake in the 1980s and now eating the eggs and fry of gwyniad.

** Donets ruffe, Gymnocephalus acerinus.

** Danube ruffe, Gymnocephalus baloni.

Of ruffe raffe roaring, with thwick thwack thurlery bouncing.

The ruffe has the capacity to reproduce at an extremely high rate.

A Ruffe usually matures in two to three years, but a ruffe that lives in warmer waters has the ability to reproduce in the first year of life.

One week after the hatching, the young ruffe start to swim and feed actively, but they do not form schools at this age.

Generally, female and male ruffe do not live longer than 7 to 11 years.

The ruffe has similar eating habits, as well as having an accelerated reproduction rate compared to other like fish.