Great Lakes Fishery Commission

Updated 2026-07-28 15:16:39

Lake Erie-2021-2025 -> 3.0 Rehabilitation Species -> Cisco Rehabilitation

Other species of interest for rehabilitation

Cisco, also known as lake herring (Coregonus artedi), played a historically important ecological role as the primary native coldwater prey fish in Lake Erie and once supported the largest commercial fishery in the Great Lakes (Smith 1951). The population collapsed in 1925 (Hartman 1972) due to over-fishing, though a limited fishery persisted in Long Point Bay until the 1950s (Oldenburg et al. 2007). Although cisco are considered extirpated in Lake Erie, 56 fish thought to be cisco were captured primarily in commercial fishery gillnets and trawls between 1995 and 2025. Most of these fish resembled hybridized deepwater forms from Lake Huron while only a few resembled the form known to have existed in Lake Erie historically (Eshenroder 2016). Genetic analysis also confirmed that recently captured fish in Lake Erie resemble deepwater forms from Lake Huron rather than the historic (1920s and 1930s) Lake Erie stock. Regardless of their origin, these infrequent observations are not enough to consider these cisco to be part of a self-sustaining population. 

Several additional research initiatives seek to address knowledge gaps identified in the Lake Erie Committee document “Impediments to Cisco Rehabilitation in Lake Erie” (CWTG 2018).  Expert panels were elicited in preparation for Lake Erie restoration plans to develop spatial unit delineation based on historical and contemporary information (Egan et al. 2024), assess current threats to cisco restoration, and implement a population viability analysis for Lake Erie cisco (Lee et al. 2025).

In 2025, New York began the first year of a ten-year stocking plan to inform rehabilitation of cisco in Lake Erie (Robinson and Markham, 2024). The goal of this plan is to determine if cisco stocked into the New York waters of Lake Erie can survive to adult life stage. Another stocking experiment used acoustic-tagged adult (age-4) hatchery-reared cisco to assess the survival and describe habitat use in contemporary Lake Erie (Kraus et al. 2024). Additional research projects are underway assessing potential methods of detection of naturally reproduced Lake Erie cisco, including eDNA and larval assessment, as the stocking plans progress.