Post-stocking survival, movement, and habitat use of bloater in Lake Ontario: updates from a 4-year

Session: Restoration and Management of Great Lakes Fishes (2)

Natalie Klinard, Great Lakes Institute for Environmental Research - University of Windsor, [email protected]
Jordan Matley, University of Windsor, [email protected]
Michael Connerton, SUNY ESF, [email protected]
Edmund Halfyard, Nova Scotia Salmon Association, [email protected]
Aaron Fisk, University of Windsor, [email protected]
Timothy Johnson, Ontario MNRF, Glenora Fisheries Station, [email protected]

Abstract

Until the mid-1950s, a diverse group of deepwater ciscoes including bloater (Coregonus hoyi) were part of Lake Ontario’s native fish community, now reduced to a single shallow-water species (C. artedi). Plans to re-establish a self-sustaining population of deepwater ciscoes in Lake Ontario consist of stocking ?500,000 hatchery-reared bloater yearly. To determine the post-stocking movement, habitat use, and survival of hatchery-reared bloater, we implanted 365 yearling bloater with acoustic transmitters between 2015-2018 and released these fish intermixed with the restoration stocking bloater in eastern Lake Ontario. Tagged individuals were tracked on an array of 105 acoustic receivers in the St. Lawrence Channel. Detections have revealed strong diel vertical migrations of bloater beginning immediately after release and high dispersal within the first two weeks. This presentation will include updated movement, habitat use, and survival of tagged bloater, focusing on results from our last array download in June 2019 of 48 bloater tagged with transmitters that will detect predation events. Establishing a self-sustaining population of deepwater ciscoes will help restore fish native to Lake Ontario, thus increasing biodiversity, improving food web stability, and serving as a basis for reintroduction and management of other native species throughout the Great Lakes.