This project aims to capitalize on the vast availability of otolith samples from commercially fished species as repositories of genomic data by employing a whole-genome resequencing approach that entails both small-scale (spike-in) and high-output sequencing. Using otolith and tissue samples from circumpolar distributions of Antarctic toothfish (Dissostichus mawsoni), we are able to identify millions of high quality SNPs that will ultimately be able to be used to address questions of population dynamics, demography, and local adaptation to environmental change.