The upper Cheboygan River has been treated with lampricides on a 4-year cycle for nearly 50 years at an average treatment cost of $400,000. Upstream escapement of sea lampreys through a navigational lock near the dam has been hypothesized to be the source of infestation in the upper river. During 2011, we tested this hypothesis and estimated escapement to be between 0 and 2% (95% CI; Holbrook et al. 2014). The very low escapement rate did not support the hypothesis that escapement of adult sea lampreys from the lower river entirely supported the upper river infestation. An alternative hypothesis is that the upper river supports a sea lamprey population that completes its life cycle without entering Lake Huron. Collective results from 2013 and 2014 provide evidence that a small population of adult sea lampreys (n < 200) completed their life cycle in the upper Cheboygan River during each year and that upstream escapement rate of adult lampreys from the lower river to the upper river through the navigational lock was still low (<5%; Johnson et al. in review). Because the adult sea lamprey population in the upper Cheboygan River is small and has low immigration rates, it should be vulnerable to control tactics that reduce reproduction such as the sterile male release technique (SMRT). Here, we propose to continue collecting data during 2016 such that if sterile males are released in the upper Cheboygan River during 2017-2019, impacts to embryo viability and larval abundance can be determined by comparing pre-SMRT years with SMRT years. Our overall objective is to determine if the release of high ratios of sterile to normal males in a watershed with low adult density reduces embryo viability, larval abundance, and lampricide treatment frequency. Here, we propose to collect pre-SMRT data by completing the following tasks during 2016: (1) Estimate adult sea lamprey abundance in the upper Cheboygan River and respective contributions from a landlocked population and escapement through the lock. (2) Estimate stream-wide abundance, length frequency, and spatial distribution of larval sea lampreys in the Pigeon, Sturgeon, Maple, and Ocqueoc River before and after lampricide treatment, and (3) estimate viability of sea lamprey embryos in nests from the Pigeon, Sturgeon, Maple, Ocqueoc, and St Marys rivers.
CONTROL SEA LAMPREYS IN THE CHEBOYGAN RIVER WITH STERILE MALES: STAGE 1 – ASSESSMENT PRIOR TO STERILE MALE RELEASE.
USGS (United States Geological Survey $ 0.00USDEstimates
Funding 15 projects for a total of $273,800.00
Great Lakes Fishery Commission $ 0.00USDEstimates
Funding 3 projects for a total of $62,822.00
U.S. Fish and Wildlife Service $ 0.00USDEstimates
Funding 4 projects for a total of $7,000.00
Fisheries and Oceans Canada $ 0.00USDEstimates
Funding 4 projects for a total of $45,500.00