Lake Sturgeon, Lake Whitefish, and Walleye Egg Deposition Patterns with Response to Fish Spawning Substrate Restoration in the St. Clair–Detroit River System

Abstract

Egg deposition and use of restored spawning substrates by lithophilic fishes (e.g., Lake Sturgeon Acipenser fulvescens, Lake Whitefish Coregonus clupeaformis, and Walleye Sander vitreus) were assessed throughout the St. Clair–Detroit River system from 2005 to 2016. Bayesian models were used to quantify egg abundance and presence/absence relative to site‐specific variables (e.g., depth, velocity, and artificial spawning reef presence) and temperature to evaluate fish use of restored artificial spawning reefs and assess patterns in egg deposition. Lake Whitefish and Walleye egg abundance, probability of detection, and probability of occupancy were assessed with detection‐adjusted methods; Lake Sturgeon egg abundance and probability of occurrence were assessed using delta‐lognormal methods. The models indicated that the probability of Walleye eggs occupying a site increased with water velocity and that the rate of increase decreased with depth, whereas Lake Whitefish egg occupancy was not correlated with any of the attributes considered. Egg deposition by Lake Whitefish and Walleyes was greater at sites with high water velocities and was lower over artificial spawning reefs. Lake Sturgeon eggs were collected least frequently but were more likely to be collected over artificial spawning reefs and in greater abundances than elsewhere. Detection‐adjusted egg abundances were not greater over artificial spawning reefs, indicating that these projects may not directly benefit spawning Walleyes and Lake Whitefish. However, 98% of the Lake Sturgeon eggs observed were collected over artificial spawning reefs, supporting the hypothesis that the reefs provided spawning sites for Lake Sturgeon and could mitigate historic losses of Lake Sturgeon spawning habitat.

Sequence analysis and acoustic tracking of individual lake sturgeon identify multiple patterns of river–lake habitat use

“…, Fischer et al. ). In contrast, our study suggested these segments were also used for feeding and overwintering.…”

“…, Fischer et al. ), but presumably the long‐term residence of lake sturgeon in these segments required access to non‐spawning resources, for example, feeding areas. In general, the segments of high lake sturgeon use in both rivers had diverse invertebrate communities, variable flow rates, complex physical structures, and substrates with mixtures of sand and clay relative to the other segments (see Tables and for comparisons of physical and biological characteristics).…”

An Assessment of an Unsuccessful Restoration Project for Lake Sturgeon Using Three‐Dimensional Numerical Modelling

“…; Krieger and Diana ; Fischer et al. ). In contrast, the Ouareau River site was deemed to have experienced a loss of habitat quantity and function due to a landslide event in 1990 that covered the traditional spawning site (Figure ) with clay and silt deposits.…”

Determination of optimal feeding rates for juvenile lake sturgeon ( Acipenser fulvescens) fed a formulated dry diet

“…As a result of these impacts, lake sturgeon has since been listed as a threatened species under the State of Michigan's Endangered Species Act (MCL 324.3605, 1994 PA 451) and ranked as a priority for conservation and management in the Great Lake regions (Holey, Baker, Thuemler, & Elliott, ). Rehabilitation efforts including restoration of migratory routes, protection of spawning and non‐spawning habitats and stocking programmes are ongoing as a means to restore lake sturgeon populations throughout the region (Fischer et al, ; Hayes & Caroffino, ; Manny & Kennedy, ; Peterson, Vecsei, & Jennings, ). Hatchery supplementation is widely advocated as an important means to achieve management goals of sustainable populations of this fish (Crossman et al, ).…”