Advancing the Science of Animal Migration

Two sea lamprey migrating in the White River, Michigan that were tracked with acoustic telemetry (video: H. Pederson, Innovasea)

Objectives: Development of a comprehensive, mechanistic model of sea lamprey migration, focused on elucidation of orientation, navigation, and habitat selection processes. The complete model can be used to predict movement paths in places where managers may wish to guide migrants towards traps or streams targeted for control actions, or towards fish passage devices where conservation of lampreys is desired. We are particularly interested in the roles that olfactory information (attractant pheromones, repellent alarm cues) play in guiding decision-making during migration. The work is mostly in the field using acoustic and PIT telemetry, computational fluid dynamics, bathymetric mapping, and animal movement models.

Representative Papers: Griffin et al., 2025; Haas et al., 2023; Meckley et al., 2017, 2014a, 2014b.; Sabal et al., 2021.

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The Chemical & Behavioral Ecology of Fear

Sea lamprey flight in response when exposed to alarm cue extracted from sea lamprey skin (video: A. Miehls, GLFC)

Objectives: Sea lampreys, like many fishes, use an alarm cue to detect and avoid areas where predators are attacking conspecifics. Alarm cues are mixtures of chemicals released from damaged tissue that induce anti-predator responses (e.g., the flight response in the video). We have investigated (a)alarm cue chemistry; (b) olfactory sensitivity, dose-response dynamics, and expression of threat-sensitivity; (c)mapped the expression of anti-predator responses to alarm cue in natural streams and the laboratory (d)investigated expression of downstream cognitive processes (e.g., habituation)and (e)tested application strategies that mitigate these effects. Each line of inquiry represents a necessary step in the development of a natural odor into a repellent that may be registered for use in the management of invasive species. The work involves laboratory and field studies using acoustic telemetry and PIT telemetry, natural products chemistry, raceway studies, and whole-river activation with alarm cue.

Representative Papers: Luhring et al., 2025; Wagner et al., 2011, 2022, 2023; Bals and Wagner, 2012; Feder et al., 2024; Mensch et al., 2022 a, 2022b; Dissanayake et al., 2019, 2021;

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Reconnecting Rivers - Selective Fish Passage

Testing our first two-channel selective fish passage design in the Ocqueoc River, Michigan (photo: A. Miehls, GLFC)

Objectives: Dams large and small are used throughout the world to slow the spread of invasive species. Yet, many want to remove dams that block the free movement of organisms and materials carried by flow to ensure the continued provision of ecosystem services and the maintenance of biodiversity. This tension has fueled substantial international interest in the development of novel fish passage devices that selectively block invasive species while allowing desirable organisms to pass. We are designing and testing novel selective fish passage devices and practices that exploit the sea lamprey's reliance on chemical information and it's ability to climb studded ramps (eel ladders). We are conducing laboratory raceway studies and field tests of designs using PIT telemetry and time-to-event analysis.

Major Partner Initiatives: FishPass. A ten year effort to design and implement a selective fish passage solution on the Boardman/Ottaway River in Traverse City, MI. A $25 million facility is currently under construction: see the construction progress here.

Representative Papers: Hume et al., 2020a; Clemens and Wagner 2024 (others in preparation)

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Bio-designing Novel Control Tactics

Using a natural response to alarm cue to guide migrating sea lamprey towards a trap in an open river channel (Box 3: Sabal et al., 2021, TREE)

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As part of the SupCon initiative, alarm cue is being added to one culvert on the Traverse River (MI) to guide sea lamprey into the adjacent 'safe' culvert where a trap has been placed.

Objectives: There have been global calls for the design, prototyping, and testing of tactics for capturing or enumerating invasive fishes in rivers to improve assessments, better target control actions, and move toward achieving meaningful reductions in abundance by 'fishing down' the invasive populations. We are designing and testing new approaches to capture migrating sea lampreys using chemical cues (pheromones, alarm cue)coupled with our knowledge of how migrants use information encoded in the hydrology and geomorphology of streams to choose migration routes. We are also engaged in a global search for scientific, institutional, and traditional sources of knowledge regarding how to fish for migrating lampreys. Our efforts are focused on conceiving and prototyping new types of fishing devices and practices for use in open river channels and along coastlines.

Major Partner Initiatives: SupCon : The Supplemental Controls Initiative is a multi-year effort to combine and test alternative control tactics (non-pesticidal approaches)to achieving sea lamprey control in difficult to treat streams. Approaches include pheromone antagonists, sterile males, push-trapping using alarm cue, and several other tools. Success is being monitored using advanced genetic techniques including pedigree analysis.

Representative Papers: Haro et al., 2020, 2025; Lewandowski et al., 2024; Hume et al., 2020b; Johnson et al. 2013, 2015 a, 2015b, 2019, 2020; Wagner et al., 2018; Dawson et al., 2016.