**The title, authors, and abstract for this completion report are provided below.  For a copy of the completion report, please contact the GLFC via e-mail or via telephone at 734-662-3209**

Movement pathways and behaviour of sea lamprey around traps in the St. Marys River

R. L. McLaughlin², L. M. O’Connor³, T. Pratt³, I. Imre⁴, R. McDonald⁵, J. Barber⁶

² Integrative Biology, University of Guelph, Guelph, ON, N1G 2W1 Canada

³ Fisheries and Oceans Canada, Great Lakes Laboratory For Fisheries and Aquatic Sciences, 1219 Queen St. E., Sault Ste. Marie, Ontario P6A 2E5 Canada

⁴ Department of Biology, Algoma University College, 1520 Queen St. East, Sault Ste. Marie, Ontario Canada P6A 2G4 Canada

⁵ Fisheries and Oceans Canada, Sea Lamprey Control Centre, 1219 Queen St. E., Sault Ste. Marie, Ontario P6A 2E5 Canada

⁶ US Fish & Wildlife Service, Marquette Biological Station, 1924 Industrial Pkwy, Marquette, MI 49855 USA

August 2011

Abstract

This study investigated the behaviour of invasive sea lamprey (Petromyzon marinus) as they approached traps in the St. Marys River. Trapping could provide a valuable option for controlling sea lamprey in large rivers across the Great Lakes if trapping efficiency could be improved. An increased understanding of how sea lamprey behave as they approach traps could contribute to the needed improvements in trapping efficiency. One part of this study developed a research framework of the trapping process (encounter, entrance upon encounter, and retention upon entrance) and combined passive integrated transponder tags and video with multi-state Markov models to quantify that trapping process. Trapping efficiency was found to be low due to low rates of encounter with traps and low rates of trap entrance upon encounter. Retention of individuals within traps was 100%. Opportunities to capture sea lamprey were limited; most individuals visited a trap once and were present from 1 - 500 s (median 5 s). Rates of encounter were also higher for fertile males and females than for sterile males. A second part of this study combined acoustic and radio telemetry to track the movement paths of female sea lamprey downstream of traps. Individuals did not use a common route to approach the traps, which may account in part for the low probabilities of encounter with traps. Application of occupancy models revealed locations where sea lamprey were more likely to occur (possible trap sites) and those locations tended to be in deeper water. However, occupancy of specific locations was dynamic, varying with time-of-day and time-of-season. Efforts to improve trapping efficiency in large rivers will need to focus on increasing rates of encounter with traps and entrance upon encounter. They will also need to consider the individual, spatial, and temporal variability in behaviour exhibited by spawning-run sea lamprey.