Marine and Freshwater Research Marine and Freshwater Research Society
Advances in the aquatic sciences
RESEARCH ARTICLE (Open Access)

Otolith chemistry discriminates water mass occupancy of Arctic fish in the Chukchi Sea

Christine M. Gleason A C , Brenda L. Norcross A and Karen J. Spaleta B
+ Author Affiliations
- Author Affiliations

A Institute of Marine Science, University of Alaska Fairbanks, PO Box 757220, Fairbanks, AK 99775-7220, USA.

B Advanced Instrumentation Laboratory, University of Alaska Fairbanks, PO Box 755780, Fairbanks, AK 99775-5780, USA.

C Corresponding author. Email: christy.m.gleason@gmail.com

Marine and Freshwater Research 67(7) 967-979 https://doi.org/10.1071/MF15084
Submitted: 28 February 2015  Accepted: 14 September 2015   Published: 24 November 2015

Abstract

The microchemistry of otoliths has the potential to reconstruct fish movement patterns and habitat use between environmentally different habitats for individual age classes of Arctic marine fish. Herein, we tested the relationship between the bottom water mass from which a fish was collected and the microchemistry of the most recent growth edge of the fish’s otolith using Mg, Sr, Ba and Ca, and then determined the physical and biological factors that affected the chemical signatures. A discriminant function post hoc analysis of fish occupying bottom water masses resulted in 76% correct classification of Arctic or Polar cod (Boreogadus saida) and 82% correct classification of Arctic staghorn sculpin (Gymnocanthus tricuspis) into bottom water masses of capture when ages were pooled. By separating age classes, correct classifications into water masses of capture were as high as 87% for Arctic cod (three water masses) and 90% for Arctic staghorn sculpin (two water masses). Otolith Ba : Ca, Mg : Ca and Sr : Ca ratios were most consistently affected by bottom water temperature; the latter two were also affected by fish age and fish length. The use of otolith microchemistry to determine occupancy of water masses over time is most promising for Arctic cod, which is widespread and occupies the most thermally diverse habitats in Arctic waters.

Additional keywords: Boreogadus saida, Gymnocanthus tricuspis.


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