Mark Vinson, PhD (Former Employee)

Population assessments of fish species often rely on data from surveys with different objectives, such as measuring biodiversity or community dynamics. These surveys often contain spatial–temporal dependencies that can greatly influence conclusions drawn from analyses. Pygmy whitefish (PWF, Prosopium coulterii) populations in Lake Superior were recently assessed as Threatened by the...

In 2014, 94 paired neuston net samples (0.5 mm mesh) were collected from the surface waters of Lake Superior. These samples comprise the most comprehensive surface water survey for microplastics of any of the Great Lakes to date, and the first to employ double net trawls. Microplastic abundance estimates showed wide variability, ranging between 4000 to more than 100,000 particles/km2...

Changes in winter conditions, such as decreased ice coverage and duration, have been observed in the Laurentian Great Lakes for more than 20 years. Such changes have been hypothesized to be linked to low Coregonus spp. survival to age-1 as most cisco (Coregonus artedi) populations are autumn spawners whose embryos incubate under ice throughout the winter. The quantity of light during...

Ecosystem-based management relies on understanding how perturbations influence ecosystem structure and function (e.g., invasive species, exploitation, abiotic changes). However, data on unimpacted systems are scarce; therefore, we often rely on impacted systems to make inferences about ‘natural states.’ Among the Laurentian Great Lakes, Lake Superior provides a unique case study to...

No abstract available.

The trophic ecology of lake charr Salvelinus namaycush morphotypes from small and large lakes within their native and introduced ranges is reviewed over the past 50 years. The lake charr is an apex predator in most habitats it occupies, where it plays a significant role in defining food webs. While often considered piscivores, lake charr feed on a range of aquatic prey throughout their...

This report describes the status of fish species and their habitat in Lake Superior during the reporting period of 2012-2016 in response to achievement of fish community objectives (FCOs) established by fishery managers for the lake. The overarching goal for the FCOs continued to be met as the fish community remained diverse, self-regulating, dominated by indigenous species, and able to...

With the exception of lake whitefish (Coregonus clupeaformis), relatively little is known about the early life history of larval coregonines in the Laurentian Great Lakes. For example, our knowledge of the feeding ecology of larval coregonines (excluding lake whitefish) is based on only 900 stomachs reported in the literature. Here, we describe the diets and demographics of larval...

The Laurentian Great Lakes have experienced recent ecosystem changes that could lead to reductions in adaptive capacity and ultimately a loss of biodiversity and production throughout the food web. Observed changes in Great Lakes benthic communities include declines of native species and widespread success of invasive species like dreissenid mussels in all but Lake Superior...

Four lake trout, Salvelinus namaycush, Walbaum 1792 morphs occur in Lake Superior: lean, siscowet, humper, and redfin. Diets of lean and siscowet have been relatively well described. However, less is known about diets of humper and redfin, and overall few studies have been conducted at offshore shoals. We compared gut content data among mature (357–867 mm) sympatric lake trout morphs...

Fatty acids are well-established biomarkers used to characterize trophic ecology, food-web linkages, and the ecological niche of many different taxa. Most often, fatty acids that are examined include only those previously identified as “dietary” or “extended dietary” biomarkers. Fatty acids considered as nondietary biomarkers, however, represent numerous fatty acids that can be extracted...

Several species of ciscoes Coregonus, subgenus Leucichthys that are native to the Laurentian Great Lakes are rare or extirpated. The restoration of Coregonus fishes is being actively pursued through stocking, and success may depend on the availability of unoccupied niche space. We described the spring–summer habitat occupancy and diets of three native cisco species (Bloater Coregonus...