AUTHORS: Maxwell D. Majinska, Quantitative Fisheries Center, Michigan State University; Christopher L. Cahill, Quantitative Fisheries Center, Michigan State University; Christopher S. Vandergoot, Great Lake Acoustic Telemetry Obersvation System
ABSTRACT: Lake Sturgeon Acipenser fulvescens reintroduction efforts are underway throughout the Great Lakes, often through the stocking juvenile fish. However, little is known about juvenile life-history and system-specific behaviors due to historical population declines prior to detailed scientific study, complicating effective management. Due to late maturation (15-25 years) and natal homing behavior of adults, understanding movement patterns of juveniles may provide useful data for evaluating reintroduction goals.
In 2017, the Saginaw River Basin was selected by the Lake Huron Lake Sturgeon Working Group for reintroduction after being functionally extirpated. Age-0 sturgeon are stocked in four rivers: the Cass, Flint, Shiawassee, and Tittabawassee. Natal streamside rearing is not currently proposed for this system; therefore, fish are sourced from the Black River Streamside Rearing Facility (BRSF, Onaway, MI) and the Genoa National Fish Hatchery (GNFH, Genoa, WI). Paired stocking provides a unique opportunity to compare the behavior of fish reared in different settings – non-natal streamside versus traditional groundwater – while using fish from the same genetic unit.
Our study evaluated movement patterns of stocked juvenile sturgeon released in 2022 and 2023 using passive acoustic telemetry. Fish (n = 80) from each hatchery were surgically implanted with InnovaSea V7 or V7D transmitters and stocked proportionally by tag type and hatchery origin among the four tributaries annually. Movement patterns were assessed by measuring total distance traveled, time to first detection, river residence time, and last known location. Preliminary results suggest BRSF fish begin moving downstream later; however, both hatcheries exhibit similar residence time and total travel distance.
