Maraena
D-Ostseeschnäpel; GB-Maraena, whitefish; DK-Helt; PL-Sieja; EST-Merisiig; RU-сея; FIN-Siika; S-Älvsik
Characters
1) Adipose fin.
2) "Nose-like" mouth.
3) Mouth small, inferior.
●) Body covered with homogenously silvern shining scales.
Often 40 to 50 cm, max. 75 cm length.
Similar species
Vimba - without adipose fin; body markedly higher; anal fin longer.
Vendace - mouth small, terminal to slightly superior; snout not protruding.
Biology
After reaching sexual maturity with 3 to 5 years the fish migrate upstreams and hibernate in arms of a river, were they also spawn. Young individuals migrate back to Sea during foraging.Diet
They feed on zooplankton like crustaceans and larvae, on bottom-living invertebrates and occasionally smaller fish.Importance
Of small importance as foodfish.Endangerment
Clear decline of stocks due to water pollution, river constructions and overfishing. Eggs are sensible to poorness in oxygen (this occurs due to algae bloom in over fertilized waters).Remarks
By means of stocking programs in Europe it is attempted to stabilize the populations. Specialists distinguish several forms, partially regarded as own species, e.g. Coregonus widegreni is more slender and less pronouced "nose" as C. maraena. Coregonus species often are placed in an own family: Coregonidae.Coregonus maraena
