Growth changes in plaice, cod, haddock and saithe in the North Sea: a comparison of (post-)medieval and present-day growth rates based on otolith measurements

L.J. Bolle, A.D. Rijnsdorp, W. van Neer, R.S. Millner, P.I. van Leeuwen, A. Ervynck

Research output: Contribution to journalArticleAcademicpeer-review

36 Citations (Scopus)

Abstract

Fishing effort has strongly increased in the North Sea since the mid-19th century, causing a substantial reduction in the population size of exploited fish stocks. As fisheries research has developed simultaneously with the industrialisation of the fisheries, our knowledge of population dynamics at low levels of exploitations is limited. Otoliths retrieved from archaeological excavations offer a unique opportunity to study growth rates in the past. This study compares historical and present-day growth rates for four commercially important demersal fish species. A total of 2532 modern otoliths (AD 1984 1999) and 1286 historical otoliths (AD 1200 1925) obtained from archaeological excavations in Belgium and Scotland were analysed. Comparison of the growth patterns between eras revealed a major increase in growth rate of haddock, whereas growth changes were not observed in saithe and only in the smaller size classes of plaice and cod. Comparison of our results with literature data indicates that the observed growth rate changes in plaice and cod occurred within the 20th century. Apparently the onset of industrialised fisheries has not greatly affected the growth of plaice, cod and saithe populations in the North Sea. This result contradicts the expectation of density-dependent limitation of growth during the era of pre-industrialised fishing, but is in agreement with the concentration hypothesis of Beverton (Neth. J. Sea Res. 34 (1995) 1) stating that species which concentrate spatially into nursery grounds during their early life-history may saturate the carrying capacity of the juvenile habitat even though the adult part of the population is not limited by the adult habitat
Original languageEnglish
Pages (from-to)313-328
JournalJournal of Sea Research
Volume51
DOIs
Publication statusPublished - 2004

Keywords

  • pleuronectes-platessa l
  • size-selective mortality
  • length-at-age
  • dutch wadden sea
  • solea-solea l
  • juvenile growth
  • concentration hypothesis
  • back-calculation
  • reaction norms
  • density

Fingerprint

Dive into the research topics of 'Growth changes in plaice, cod, haddock and saithe in the North Sea: a comparison of (post-)medieval and present-day growth rates based on otolith measurements'. Together they form a unique fingerprint.

Cite this