The seasonal cycle of condition in the pollan, Coregonus autumnalis pollan Thompson, of Lough Neagh, Northern Ireland

The length–weight relationship for Lough Neagh pollan was log W= 3·2 log L –2·24. Covariance analysis indicated that there were no differences between the sexes, with maturity, or between years. While a seasonal cycle in relative condition was in phase with gonad development during late summer and autumn, changes in somatic condition presented a more complex pattern. Somatic condition increased in spring, as did the quantity and diversity of food consumed. Despite good conditions for feeding and growth, there was an autumn fall in somatic condition, caused by the diversion of energy to gonad growth.