The relationship between stock and recruitment:are the assumptions valid?

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 196:305-309 (2000) - doi:10.3354/meps196305 The relationship between stock and recruitment: are the assumptions valid? M. Cardinale*, F. Arrhenius Institute of Marine Research, National Board of Fisheries, PO Box 4, 45321 Lysekil, Sweden *E-mail: mascar@imr.se ABSTRACT: The management of exploited fish populations is, at present, based on stock assessment methods which assume that spawning biomass is proportional to the reproductive potential of the stock. This implies that the survival rates of offspring do not substantially change with the age or size of the spawner. However, the commercial extinction of many fish stock worldwide has provoked concern about the techniques used in stock assessment. Is the contribution of different age classes to recruitment equal, irrespective of the age of the fish? Here we show that not only do older individuals contribute the largest amount of eggs to the reproductive potential of cod Gadus morhua, but that they also have the largest number of recruits likely to produce offspring with higher rates of survival. This important effect of population structure on recruitment should be taken into account in fisheries science and fisheries management. KEY WORDS: Stock assessment · Recruitment · Parental age · Population strucure · Generalized Additive Model Full text in pdf format PreviousExport citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 196. Publication date: April 18, 2000 Print ISSN:0171-8630; Online ISSN:1616-1599 Copyright © 2000 Inter-Research.