Líffræðifélag Íslands - biologia.is
Líffræðiráðstefnan 2017

Erindi/veggspjald / Talk/poster V43

Stable isotope, δ13C and δ15, examination of trophic shifts in five commercial marine fish species across the last Millennium, AD 971 – AD 1910.

Höfundar / Authors: Guðbjörg Ásta Ólafsdóttir (1), Ragnar Edvardsson (1), Sandra Timsic (2), William P Patterson (2)

Starfsvettvangur / Affiliations: 1. University of Iceland, Research Centre of the Westfjords 2. Saskatchewan Stable Isotope Laboratory, University of Saskatchewan

Kynnir / Presenter: Guðbjörg Ásta Ólafsdóttir

Zoo-archaeological material from historical fishing sites around Iceland allows unparalleled opportunities for long-term retrospective examination into fish stocks; and thereby predictions on how fish stocks may respond to future change. Marine fish are often highly flexible foragers and many North Atlantic fish are subject to shifts in feeding migrations and distribution; either in response to climate changes or to shifts in prey distributions. Examining the trophic response of commercial fish to past environmental fluctuations is therefore instrumental for modern fisheries science. Stable isotopes δ13C and δ15N have often been used as proxies for ecological variables in the marine environment, such as tropic level, niche width and overlap and have documented other ecological processes; including changes in individual metabolism and primary production. Time series of museum specimens have been used to reconstruct historical marine trophic dynamics in relation to population change and demographics and prehistoric biological material to document niche shifts. We present preliminary examinations of stable isotope values, δ13C and δ15N, for five common North Atlantic fish species across the last millennium, AD 971-AD 1910. Specifically, we examine Gadus morhua, Melanogrammus aeglefinus, Sebastes sebastes, Anarhichas lupus and Hippoglossus hippoglossus.