After relatively good mackerel fishery at Calicut in 1980-81 it touched the lowest figure in 1983-84. Improvement was noticed subsequently. Recruitment to the fishery is almost completed by September. Mainstay of recruitment at Calicut is from the products of spawning in June and August. A good annual rainfall is found to be beneficial to the fishery, but the rainfall and catch in September is found to have an inverse relation. Catch in 1970-71 is found to be well above equilibrium level. The magnitude of spawning stock in April-June period is found to have direct relation to the total catch of that season. In general, mackerel fishery is on the decline at Calicut. There are indications that the current fishing pressure on the population is more than optimum.