**ABSTRACT NOT FOR CITATION WITHOUT AUTHOR PERMISSION. The title, authors, and abstract for this completion report are provided below.  For a copy of the full completion report, please contact the author via e-mail at hdawson@umflint.edu or via phone at 810-762-3360. Questions? Contact the GLFC via email at frp@glfc.org or via telephone at 734-662-3209.**





 Heather A. Dawson1, Gale Bravener2, Josh Beaulaurier1, Nicholas S. Johnson3, Michael Twohey4, Robert L. McLaughlin5


1Biology Department, University of Michigan-Flint, 264 Murchie Science Building, Flint, MI 48502.

2Fisheries and Oceans Canada, Sea Lamprey Control Center, 1219 Queen Street East Sault Ste. Marie ON P6A 2E5.

3USGS, Great Lakes Science Center, Hammond Bay Biological Station, 11188 Ray Road, Millersburg, MI 49759.

4US Fish and Wildlife Service, Marquette Biological Station, 3090 Wright St., Marquette, MI 49855.

5Department of Integrative Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada



April 2014





For traps to function as an alternative method of controlling sea lamprey, capture efficiency of adult sea lampreys must be high enough to reduce larval recruitment. To be captured, sea lampreys must come close to the trap (encounter), move through the trap opening into the trap (entrance) and remain in the trap (retention) until they are removed. We hypothesize that patterns observed in daily trap catches (a measure of trapping success) are also observed in the probabilities of trap encounter, entry, and retention (measures of sea lamprey behavior) and that trap catches can be increased by understanding factors influencing these probabilities. We determined whether factors that can be controlled by trap operators, such as pheromone application and stream discharge, are associated with the numbers of trap encounters, and probability of trap entry and retention. Sea lamprey behavior was observed using underwater video at entrances of five traps in three different Great Lakes streams (in two Great Lakes) across five sea lamprey migration seasons. Probabilities of encounter, entry, or retention, and ultimately trap success, were not related to discharge, but were related to the application of pheromone during certain times of season. Trapping could be improved in Carp Lake Outlet by using pheromones and employing more effective retention devices. Trapping could be improved in the St. Marys River by increasing the number of traps, using new trap designs, improving trap placement, and using pheromones. New permanent traps have been constructed in the Cheboygan River since this study; hence no recommendations are provided for this new trap.