The Decline of Michigan's Lake Huron Charter Fishery: Is It the Economy, or Is It Fish?

Charter fishing effort in Michigan waters of Lake Huron declined by 50% from 2002 to 2010.  Declines in catch rates, rising gasoline prices, and the economic downturn are often mentioned as possible reasons for the decline in charter fishing effort.  To better understand the relative importance of these factors, five catch-based and six economic variables were evaluated along with time-lag factors using data from 1992-2010.  Catch-based variables included non-charter angler CPUE for Chinook salmon, Chinook and coho salmon, lake trout, and all salmonines.  Economic variables included total employment and unemployment rates for Michigan and the Detroit metropolitan area, U.S. gross domestic product, and the price of gasoline during the fishing season.  Chinook salmon catch rate and a 1-year lag time explained 90% of variation in charter fishing effort and was the best-performing model in all-subsets regression.  The best-performing economic variable was mean gasoline price over the past two fishing seasons.  Although mean gasoline price alone was a good predictor of charter effort (R² = 0.805), it did not perform well in all-subsets regression.  Understanding the relative importance of economic vs. catch-based factors in driving effort could help fisheries managers understand how much influence their actions are likely to have on fishing activity.