Assessment surveys for capelin in the Iceland–East Greenland–Jan Mayen area, 1978–2001

The directed fishery for capelin in the Iceland–East Greenland–Jan Mayen area began in the mid-1960s as a February–March fishery in coastal waters and yielded about 100 000–200 000 t annually. By the late 1970s it had expanded geographically and seasonally, with annual catches at about 1 000 000 t. The fishery continued at about that level and aimed at the mature or maturing part of the stock. Preliminary catch quotas were based on acoustic estimates of juvenile capelin and final Total Allowable Catches were determined using estimates of maturing adults, measured during the fishery. Both juveniles and adults can theoretically be estimated from the same autumn acoustic survey. However, in many years, the abundance of the maturing fishable stock could be assessed only after the survey was repeated, because either scientists or the fishing industry determined that the first estimates were not realistic. The distribution of capelin during autumn in this area is unpredictable owing to annual variations in environmental conditions. In contrast, in the Barents Sea and off Newfoundland, the approach has been to employ single annual acoustic surveys. The advantages, disadvantages, and historical record of Iceland's repeat-survey approach are discussed.