Fish otolith chemistry for environmental assessments

The purpose of this project was to determine value of Fish Otolith chemistry as a tool for environmental assessment in Yukon as it may relate to mining sites and improve aquatic wildlife protection. This technique has been developed over the last decades and applied at different locations, but not yet in the Yukon.

The goals of this project were two-fold, 1) apply Fish Otoliths Chemistry technique at the Keno Hill District and 2) share knowledge and discuss the results and potential application with local community, scientific community, regulators and decision-makers.

Project Overview

Fish otolith chemistry integrates information on contaminant exposure and life history of both individual fish and populations. Furthermore, it has the potential to advance our understanding of the local ecosystem and to become an additional technique in the environmental assessment and monitoring toolbox. 

Improvement of the environmental assessment and prediction of potential impact of land use activities rely on the development of scientific tools and techniques which are a critical part of all mining developments. This technique has the potential also to provide First Nation peoples, other Northerners, and regulators with robust data to inform land use and watershed decisions in Yukon.

Fish otoliths chemistry affords a unique opportunity: otoliths consist of a calcium carbonate structures in the inner ear of fish deposited in daily to annual increments that have been used to determine age and life history events of fish and fish populations. As otoliths are metabolically stable, the contaminant levels within their annular structure can provide temporal record of the exposure of the fish to trace metals and can be used to get baseline data information required for environmental assessments and reconstruct historical exposure for the further protection of aquatic wildlife.

As new mining projects are developing, Yukon could benefit in establishing fish otoliths chemistry technique and database in the territory with the local population.

Project Team

Principal Investigators

David Petkovich, General Manager, Access Consulting Group

Pr. Norman Halden, Dean Clayton H. Riddell Faculty of Environment, Earth, and Resources, University of Manitoba.

Project Advisors

Jody Mackenzie-Grieve, Federal Contaminated Sites Program Biologist, Fisheries & Oceans Canada

Bob Truelson, Manager, Water Quality Unit, Yukon Environment

Pat Roach, Yukon Regional Contaminants Committee Coordinator, Aboriginal Affairs and Northern Development Canada

Martin Haefele, Permitting Manager, Capstone Mining Corp.

Darrel Otto, Instructor, Yukon College


Na-Cho Nyak Dun First Nation

University of Manitoba 

Access Consulting Group

Department of Fisheries and Oceans Canada

Yukon Environment


Capstone Mining Corp


Yukon Fish and Wildlife Enhancement Trust