Precision and accuracy of Dahl-Lea back-calculated smolt lengths from adult scales of Atlantic salmon Salmo salar

J Fish Biol. 2019 Jan;94(1):183-186. doi: 10.1111/jfb.13863. Epub 2018 Dec 27.

Abstract

Using tagged and recaptured Atlantic salmon Salmo salar (n = 106) the present analysis shows that the most commonly applied linear back-calculation method for estimating past length, the Dahl-Lea method, resulted in overestimation of the length of large smolts and underestimation of small smolts. A correction equation (y = 0.53x + 6.23) for estimating true smolt length (y) from lengths back-calculated from adult scale measures (x) to account for these systematic discrepancies is proposed.

Keywords: Salmo salar; allometry; back-calculation; circuli; growth; increment analysis.

MeSH terms

  • Animal Migration
  • Animals
  • Models, Biological*
  • Rivers
  • Salmo salar / anatomy & histology
  • Salmo salar / growth & development*