Biology

In Britain the vendace occurs only as non-migratory freshwater populations, but in the Baltic it occurs as anadromous populations (they spend most of their time in saltwater and migrate to freshwater to spawn) (7). The vendace feeds primarily on free-swimming organisms such as water fleas (6) and planktonic crustaceans (5). Spawning occurs in November and December (6); adults move to the edges of lakes, and females scatter the small two millimetre diameter yellow to orange eggs in gravely areas in still water (6). The eggs are fertilised externally and develop slowly on the bottom of the lake (7), hatching the following spring (2). Individuals are thought to live up to six years of age (2).