Relative Survival, Movements, Reproduction, and Fishery Contribution of Chinook Salmon in Lakes Michigan and Huron As Determined from Coded-Wire Tags

Millions of salmonines are annually stocked in the Great Lakes to support and diversify sport fisheries, restore native fish populations, and control invasive fishes. In 2011 the Great Lakes Mass Marking Program, in partnership with the states, began coded-wire tagging and adipose-fin clipping all Chinook salmon stocked into Lakes Michigan and Huron to better understand movement patterns, contribution of stocked fish to fisheries, and levels of natural reproduction.  Data and tag recoveries from our field network helped describe movement patterns of stocked Chinook salmon from various ages, year classes, and seasons.  Fish have been recovered up to 520 km away from their stocking location (ave. = 140 km), but move closer to stocking locations as they mature.  Early findings suggest greater fishery contributions (i.e., recoveries per number stocked) from Chinook salmon stocked along the western shore of Lake Michigan, and also indicate substantial movement of Chinook salmon from Lake Huron into Lake Michigan with limited reciprocal movement.   We also describe levels of natural reproduction for Chinook salmon in various districts (ave. 59.8% in L. Michigan and 55.4% in L. Huron across all ages).  Our preliminary results show that coordinated basin-wide, muti-agency tagging efforts enhance understanding of Great Lakes fisheries.