Stock-related effects in the recruitment of North Sea haddock and whiting

Cook, R. M. and Armstrong, D. W. (1986) Stock-related effects in the recruitment of North Sea haddock and whiting. Journal du Conseil - Conseil International pour l'Exploration de la Mer, 42 (3). pp. 272-280. ISSN 0020-6466

Full text not available in this repository.Request a copy from the Strathclyde author

Abstract

A model is developed which describes recruitment in haddock Melanogrammus aeglefinus by the separate effects of total stock and spawning stock. Whilst spawning stock makes an approximately proportionate contribution to egg production, the total stock has an adverse effect on subsequent recruitment. Pre-recruit mortality, which is related to total stock size, appears to be the operative factor. The model can account for c 40% of variation in log recruitment. In whiting Merlangius merlangus c 22% of the variation in log recruitment can be attributed to the negative effect of total stock size. There is no detectable separate spawning-stock effect. -from Authors