Oxytetracycline (OTC) Markers

No Reporting Needed

Anglers will not be able to determine if a fish has been marked with Chemical Markers - OTC. Typically this marking procedure is used to identify hatchery versus naturally-reproduced fish. OTC samples are collected by agency personnel.

Additional Information about Chemical Markers:

• Lakewide Assessment of the Contribution of Natural Recruitment to the Chinook Salmon Population of Lake Huron
  This study objectives include determining Lake Huron chinook salmon natural recruitment & reproduction, and refining bioenergetics and catch-at-age recruitment models.
• Analysis of Chinook Salmon Populations of Lakes Huron and Michigan, 1985-2004
  OTC marks were used to determine natural reproduction of chinook salmon in both lakes Huron and Michigan.
• Influence of Lotic and Nearshore Habitats on Fish Populations in Great Lakes and Inland Lake Ecosystems, with Emphasis on Walleye
  One study objective was to assess the natural reproduction of walleye in Michigan waters of Green Bay by the use of an OTC mark on all stocked fish.
• Status of Saginaw Bay Walleye Population and Progress Towards Recovery
  Due to the stocking of OTC-marked fish, it was determined that the strong year classes of the last few years are wild (or naturally reproduced) walleye.