Date of Award


Publication Type

Master Thesis

Degree Name



Great Lakes Institute for Environmental Research


Acoustic telemetry, Bloater, Deepwater cisco, Detection efficiency, Lake Ontario, Spatial ecology


Aaron Fisk


Timothy Johnson




Fish stocking is a common practice in freshwater and marine systems worldwide aimed to supplement naturally occurring wild populations, re-establish extirpated species, or introduce non-native species for recreation or management. Bloater (Coregonus hoyi), a deepwater cisco extirpated from Lake Ontario in the 1980s, are stocked annually with the aim of re-establishing a self-sustaining population. However, challenges exist in determining the fate of bloater post-release due to difficulty monitoring them, an issue for stocked fish worldwide. This thesis used acoustic telemetry to determine the post-stocking movement, behaviour, and survival of hatchery-reared bloater in Lake Ontario and evaluated the performance of acoustic telemetry in a large, freshwater lake. Detection range testing revealed the probability of a receiver detecting a transmission from an acoustic transmitter in Lake Ontario varied both spatially and temporally and was influenced by dynamic interactions of environmental conditions, particularly ice thickness and thermal stratification. Following release, tagged bloater dispersed rapidly, underwent extensive diel vertical migrations, and exhibited survival (34%) beyond two weeks post-stocking. Collectively, this thesis presented novel information on bloater ecology to help inform reintroduction practices, demonstrated the value of acoustic telemetry in restoration studies, and addressed one of the major assumptions associated with the performance of telemetry in various environments.