ALBANY, N.Y. (AP) — Fish researchers want some help collecting the heads of Coho salmon.

The state Department of Environmental Conservation and Ontario Ministry of Natural Resources are asking people to save the heads from Coho salmon caught in Lake Ontario starting this year. It's part of an effort to evaluate the effectiveness of stocking programs.

The agencies are marking or tagging all stocked Coho salmon. Tags are 1-millimeter-long pieces of coded wire inserted into the snouts of fish. They're undetectable without specialized equipment, so the fish heads have to be collected to retrieve the tags.

Recovery of mark and tag data will continue until 2021.

DEC is asking volunteers to put the heads in labeled plastic bags and place them in freezers located at sites from the Niagara River to Oswego .