Movement of Chinook Salmon between Lakes Michigan and Huron

Grant: # 1230

Grant Amount: $259,637.94

Board Decision Year: 2012

Michigan State University - Department of Fisheries and Wildlife (East Lansing)

Department of Fisheries and Wildlife

Clark Jr., Richard ([email protected]) 517-432-5099

GLFT - Ecosystem Health and Sustainable Fish Populations-C - Ecological and biological fisheries research to inform management

Project Details

This project estimated the extent of interlake movement of Chinook salmon between Lakes Huron and Michigan and incorporated these movements into analytical tools, such as statistical catch-at-age (SCA) and predator-prey models currently in use to help managers determine how many fish to stock. Researchers hypothesized that the movement rate of Chinook salmon from Lake Huron to Lake Michigan increased from 1990 to 2014 and that this movement contributed to an increase in abundance of salmon in Lake Michigan and a decrease in Lake Huron. Accounting for these movements could be relevant to determining stocking rates of Chinook salmon in both lakes.

First, researchers showed that catch per effort (CPE) of Chinook salmon, an index of population abundance, increased in Lake Michigan over the same time period that CPE decreased in Lake Huron. While many factors could have been involved in these changes, researchers concluded that interlake movement of Chinook salmon from Huron to Michigan was likely a contributing factor. Second, to provide direct physical evidence of movement, they analyzed the pattern of capture locations of tagged Chinook salmon released in each lake. Researchers also used indices of abundance of alewife populations in the two lakes to determine if any changes in movements they found correlated with changes in alewife abundance. Salmon moved from Lake Huron to Lake Michigan, where alewives were more abundant, from April to July, then back to their spawning locations during breeding season. This shift in interlake movement between April and July was equivalent to increasing the stocking rate within Lake Michigan by 30 percent. Based on these findings, researchers assert that managers should consider coordinating Chinook salmon stocking policies for these two lakes.

Documents

Final Report

View - Final_Report_for_2012.1230.pdf