During the week of September 19, Fishery Biologist Scott Koproski traveled to Sault Ste. Marie, Mich., to assist the Chippewa Ottawa Resource Authority (CORA) with their annual juvenile walleye assessment of the St. Marys River.  Using the Alpena Fishery Resources Office's electrofishing vessel, Koproski and two CORA staff sampled four locations in the St Marys River system (Waiska Bay, Lake Nicolet, Lake George, Sugar Island Side Channel) over four nights. 

The objective of this work is to determine the percent contribution of hatchery reared walleye to the St. Marys River walleye population and to index juvenile walleye abundance.  Hatchery stocked walleye are immersed in oxytetracycline (OTC) prior to release in to the wild.  OTC leaves a mark on calcified structures like otoliths and vertebrae that can be detected in the lab.  Data collected will also be used to determine appropriate stocking levels and stocking locations for this system.  Staff from the Alpena FRO has been assisting CORA with this walleye assessment for the past 13 years.