Spatial and temporal dynamics of lake whitefish (Coregonus clupeaformis) health indicators: Linking individual-based indicators to a management-relevant endpoint

Estimates of fishing and natural mortality rates for four Lake Whitefish stocks in Northern Lakes Huron and Michigan

“…Management of lake whitefish in the Great Lakes would benefit greatly from a confirmation of existing models used to estimate natural mortality as well as from insights into possible explanations for among stock or among-year variations in natural mortality (Wagner et al, 2010). The purpose of this research was to estimate fishing and natural mortality rates from four lake whitefish stocks in northern lakes Huron and Michigan using tag-recovery and to compare these estimates with values derived from the Pauly (1980) relationship for the same stocks.…”

Sensitivity of tag-recovery mortality estimates to inaccuracies in tag shedding, handling mortality, and tag reporting

“…Our interest in how inaccuracies in shedding, handling-mortality, and reporting rates can affect estimation of fishing and natural mortality stemmed from our involvement in a project meant to clarify the relationship between indicators of fish health and natural mortality rates in four lake whitefish (Coregonus clupeaformis Mitchill) stocks in northern lakes Huron and Michigan (Wagner et al, 2010). For that study, lake whitefish were tagged with anchor tags, and the recovery and reporting of tags by commercial fishers was used to estimate fishing and natural mortality rates for the stocks (Ebener et al, 2010a).…”

Assessing the health of lake whitefish populations in the Laurentian Great Lakes: Foreword

“…Ebener et al (2010a) used onboard and dockside observers to estimate tagreporting rates of commercial fishers; however, they still suggest additional evaluations of lake whitefish natural mortality rates be conducted because of the sensitivity of estimates to tag reporting rates. Wagner et al (2010) provide a comprehensive evaluation of the spatial and temporal dynamics of, and interrelationships between, a variety of health indicators and natural mortality rates for lake whitefish stocks in northern lakes Huron and Michigan. Among the health indicators evaluated by Wagner et al (2010) were whole-body water and total lipid concentration, selected fatty acid concentrations, and C. farionis and R. salmoninarum infection intensity and prevalence.…”

“…Wagner et al (2010) provide a comprehensive evaluation of the spatial and temporal dynamics of, and interrelationships between, a variety of health indicators and natural mortality rates for lake whitefish stocks in northern lakes Huron and Michigan. Among the health indicators evaluated by Wagner et al (2010) were whole-body water and total lipid concentration, selected fatty acid concentrations, and C. farionis and R. salmoninarum infection intensity and prevalence. The natural mortality rates used as part of the Wagner et al (2010) analyses were those calculated by Ebener et al (2010a).…”

“…Among the health indicators evaluated by Wagner et al (2010) were whole-body water and total lipid concentration, selected fatty acid concentrations, and C. farionis and R. salmoninarum infection intensity and prevalence. The natural mortality rates used as part of the Wagner et al (2010) analyses were those calculated by Ebener et al (2010a). Wagner et al (2010) found that for most fish health indicators a substantial proportion of the total variation in the indicators could not be attributed to spatial or temporal sources and was instead related to variation among individuals.…”