A life table for powan, Coregonus lavaretus (L.) in Loch Lomond, Scotland: A basis for conservation strategy

Abstract1. A static life table for Loch Lomond powan, Coregonus lavaretus (L.) has been constructed from data obtained during 1980–1988, as a basis for monitoring any changes in the population which may ensue from exploitation of the Loch.2. Mortality was 99.95% during the first year of life, and adult mortality highest at 5–6 years.3. Average fecundity was 20.7 ova mm−1 fork length.4. Mortality and fecundity have not changed in 25 years.5. It is not yet possible to assess the effect of the recent introduction of ruffe, Gymnocephalus cernuus (L.) into Loch Lomond, but their effect on recruitment into the vulnerable 0–1 year‐class may be critical.