| Summary: | Vendace (Coregonus albula) has a short history (30–40 year) in Lake Inari, being introduced into the watercourse in the 1950s and 1960s. The growth of the stock was slow at the beginning, but increased rapidly in the 1980s due to three strong, successive year classes in 1983, 1984 and 1986. All these years, and also in 1989, summers were quite warm and the water temperature favourable after the ice-break. The peak stock size was recorded 1987, and after that, there was a slump. In the middle of the 1990s, the stock size had stabilized to a very low level compared with the situation in the end of 1980s, and the vendace stock concentrated mostly in the southern parts of the lake. The vendace fishery flourished for less than five years. The peak year concerning fisheries and catches was 1989 with a vendace catch of nearly 3 kg ha–1 and a total catch of about 5 kg ha–1, rather high figures in subarctic northern regions. After 1989, the vendace catch decreased rapidly. It seemed that the fishing effort of some years (1989 and 1990) was so heavy that the spawning stock size gradually decreased to a level, where the revival was difficult. Unfavourable weather conditions with cold summers at the beginning of 1990s, and, at the same time, quite hard pressure of predation by abundantly stocked salmonids on vendace contributed together to the fact that only very scanty year-classes were born. This, in turn led to a collapse of the vendace stock in the 1990s.
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