10 20 40 60 cm
mittakaava < 60 cm
Gösta Sundman: Suomen Kalat (Kansalliskirjasto, The National Library of Finland), Lauri Urho, Jouko Lehmuskallio
- Other names: European whitewish, Common whitewish, Lavaret
- Family: Salmonids – Salmonidae
- Similar species: peled, vendace
- Size: 15–55 cm, seldom exceeds 2 kg. Size varies greatly from one population to another.
- Appearance: The whitefishes in general vary considerably in body and head shape. They have posed a problem for taxonomists for many years, with attempts to classify them into species, subspecies and even different races. Probably the most often used means of identification is to count the number of gill rakers on the first gill arch. According to recent genetic studies conducted using a new technique, there are no scientific grounds for dividing the whitefish into different species. Characteristics common to the whitefishes are a tapered body, an adipose fin typical of the salmon family, and a slightly protruding upper jaw. Above the mouth is a short, tapered snout, a feature that distinguishes the whitefish from the otherwise similar vendace and peled. In the vendace it is the lower jaw that protrudes, while in the peled the jaws are of equal length. Least typical of the whitefish in terms of appearance are certain dwarf whitefish found in the lakes of Lapland; these seldom exceed 20 cm in length and may be taken for vendace. They also have disproportionately large heads and eyes, and differ from other whitefishes in their colouring. The plankton-feeding whitefishes of southern Finland’s major waterways as well as migratory sea-feeding populations that ascend rivers to spawn grow much faster and can be distinguished from vendace by their size.
- Colouring: Back dark bluish green or brown, sides silver and belly white. Fins dark grey. The dwarf populations of Lapland’s lakes may be predominantly brownish in colour.
- Reproduction: Spawns in autumn between September and November, depending on water temperature. Different whitefish populations in the same water may spawn at different times. Whitefish populations in both lakes and the sea may ascend rivers to spawn, while others may remain in the sea or lake to spawn.
- Food: Different populations again differ, but the main food items are benthic invertebrates or plankton, larger fish feeding on surface insects and small fish fry.
- Distribution and habitat: Found in freshwater throughout Finland as well as in all sea areas. Generally prefers cool, clean, well-oxygenated water.
- Endangerment: Migratory sea-feeding populations are classified as endangered.