All Chinook salmon Oncorhynchus tshawytscha stocked in Lake Huron during 2000–2003 were marked with oxytetracycline (OTC), fin clips, or a combination thereof to determine the relative contributions of natural reproduction and stocking to recruitment. Oxytetracycline administered in feed proved to be an effective, low‐cost method of marking spring fingerling Chinook salmon. Vertebrae proved to be suitable tissue for OTC detection, meeting standards for accuracy and reproducibility. Vertebrae were not suitable as aging structures, perhaps due to the slow somatic growth of Lake Huron's Chinook salmon during this study. Based on lakewide recoveries from recreational and commercial fisheries, we estimated that nearly 80% of Chinook salmon from the marked year‐classes were from natural reproduction. Wild‐origin Chinook salmon constituted 96% of open‐water samples from Georgian Bay; 82, 80, and 68% of those from the central, southern, and northern portions of the main basin; and 64% of those from the North Channel. The percentage of wild‐origin Chinook salmon in some tributaries in the Ontario watershed of Lake Huron approached 100%. There was less variation in wild recruitment between years than between lake areas. This Chinook salmon population was introduced in the late 1960s and until recently had been widely viewed as hatchery dependent; our findings suggest otherwise. A self‐sustaining predator population would represent a paradigm shift from an era when predation rates could be manipulated by adjusting salmonid stocking (i.e., 1968 to about 1995). These findings should help managers to critically review the effects of stocked Chinook salmon on Lake Huron's fisheries and ecosystem, including prey consumption demand, and to assess future needs for propagated Chinook salmon in Lake Huron.

We produced a spatially explicit assessment of the changes in stocking, catch, fishing effort, and catch per effort (CPE) for Chinook Salmon Oncorhynchus tshawytscha in Lakes Michigan and Huron from 1986 to 2011. We focused on describing spatial differences in the changes that occurred during three well‐known episodes of rapid change: (1) a decline in abundance during 1986–1994 in Lake Michigan, (2) a recovery in abundance during 1994–2006 in Lake Michigan, and (3) a decline in abundance during 2002–2010 in Lake Huron. We used a spatial grid system to describe and contrast trends in fishing effort and CPE among the main lake basins (Michigan, Huron, and Georgian) and subregions within those basins. We applied linear regressions, ANCOVAs, and Tukey's tests to assess differences. We found that trends differed among and within basins during all three episodes, which resulted in changes in the distribution of fishing effort and CPE. Fishing effort generally decreased in all basins and subregions over the entire 25 years, but it decreased less in areas where CPE had increased. The timing of the recovery episode and second mortality episode overlapped, so CPE simultaneously increased from 79 to 139 fish/1,000 h of fishing in the Michigan basin and decreased from 65 to 35 fish/1,000 h of fishing in the Huron basin. Movement of fishing effort and Chinook Salmon from the Huron basin to the Michigan basin probably occurred during this time. The CPE did not change significantly in the Georgian basin. Within basins, CPE exhibited sharp declines of more than 80% in some subregions during both mortality episodes but declined much less or not at all in others. After the recovery episode, areas of highest CPE in the Michigan basin had shifted from eastern subregions to western subregions. Received February 2, 2016; accepted April 23, 2016 Published online August 30, 2016

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We used stated-preference choice models to examine Ontario anglers' preferred outcomes from fish stocking of Lake Huron and variations in these preferences between a random and a convenience sample. Anglers preferred outcomes that decreased risks of fish stock collapses and increased native prey fish species, average fish size, and species abundance especially for walleye (Sander vitreus) and rainbow trout (Oncorhynchus mykiss). Anglers from a convenience sample that likely participate in typical consultation efforts for fisheries management were more supportive of outcomes that favored Chinook salmon (Oncorhynchus tshawytscha) and less supportive of outcomes that favored lake trout (Salvelinus namaycush) or walleye than were anglers from a random sample. From a managerial perspective, the results suggest profound differences, as a silent majority of Lake Huron anglers supported a lake trout rehabilitation outcome while Lake Huron anglers who typically voice their perspectives to managers preferred outcomes that emphasize the non-native Chinook salmon.

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