Spatial units to support Lake Erie Cisco Coregonus artedi restoration

At the request of the Lake Erie Committee, spatial units for Lake Erie Cisco were delineated during spring 2024. Spatial units correspond to the reproductive habitat of extirpated (unoccupied spatial units) and extant (occupied spatial units) populations. Spatial units were delineated using a Council of Lake Committees-endorsed method that involves synthesizing data for evaluation by a panel with expertise on the focal organisms and ecosystems. By examining catch, survey, observational, and genetic data, an expert panel determined that no viable Cisco populations remain in Lake Erie. Experts delineated one eastern and one western unoccupied Cisco spatial unit in Lake Erie based on interpretation of historical movement and spawning locations and timing. The expert panel also identified eleven key questions that can be investigated to further inform Lake Erie Cisco restoration. The two unoccupied spatial units will form the basis of a follow-on threats assessment and population viability models that together provide fishery managers science-based planning tools for Lake Erie Cisco restoration.