In response to inquires made by the Marine Stewardship Council (MSC) to the PLOS editorial office about details of the samples collected for this study, we direct readers to our previously published work (http://www.sciencedirect....) and a website prepared in response to similar inquires made three years ago by the MSC (http://markolabhawaii.org...).

The authors would like to emphasize that our most recent work published in PLOS ONE looked at whether mislabeling can potentially obscure mercury exposure risk given (1) the large amount of geographic variation in mercury accumulation in Patagonian toothfish or “Chilean sea bass,” and (2) the current focus on mean mercury levels of species in consumption guidelines.

Our previously published analyses of retail-acquired fish compared the labeling of fish to genetic data that were potentially informative about species identity and places of capture. For legal and ethical reasons, the PIs of that original study were advised by their home institution to compile, analyze, and release only those data that were used to examine the specific hypotheses of the work: the species of fish and if all fish originated from the South Georgia/Shag Rocks fishery, the only fishery certified by the MSC at the time of the study. We cannot provide specific information about stores or individuals that were involved in the actual retail transactions.

In our Data Availability Statement for the study published in PLOS ONE, we wrote that the data underlying the findings are fully available without restriction after considering the definition of a “minimal data set” as defined by PLOS: data “used to reach the conclusions drawn in the manuscript with related metadata and methods, and any additional data required to replicate the reported study.” We feel that the data underlying the hypotheses tested in this work and all information required to replicate the study are provided in this publication, our previous publication (http://www.sciencedirect....), and what has been made available on the primary author’s website (http://markolabhawaii.org...). Also, the data points used to create the graphs in Figures 2 and 3 are available on figshare.com (http://figshare.com/artic...).

We continue to hope that the MSC and other organizations will increase their support of broader efforts to curb the problem of seafood mislabeling, which is widely understood to be epidemic (http://oceana.org/en/our-...). One approach we recommend is that industries express support for better seafood mislabeling to the Presidential Task Force on Combating IUU Fishing and Seafood Fraud (http://www.nmfs.noaa.gov/...). Seafood mislabeling is a form of economic fraud that disempowers consumers that want to buy sustainable wildlife products. Here we share the MSC’s goal of providing consumers with accurate information about the identity and origin of marine wildlife that can potentially help to protect our oceans from further overexploitation.