Mackerel egg investigations in the North Sea

Abstract

This paper deals with the mackerel egg investigations in the North Sea in 1982 and 1983. The egg production is estimated by a computerized method. The confidence limits of the egg samples were estimated at 20-30%. The optimum future distribution of sampling effort in the area is calculated according to Neyman allocation. A comparison of the fecundity of mackerel from different areas measured by different methods is done. The size of the North Sea spawning stock is estimated based on the egg surveys and the fecundity studies