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Genomic tools are lacking for invasive and native populations of sea lamprey (Petromyzon marinus). Our objective was to discover single nucleotide polymorphism (SNP) loci to conduct pedigree analyses to quantify reproductive contributions of adult sea lampreys and dispersion of sibling larval sea lampreys of different ages in Great Lakes tributaries. Additional applications of data were explored using additional geographically expansive samples. We used restriction site‐associated DNA sequencing (RAD‐Seq) to discover genetic variation in Duffins Creek (DC), Ontario, Canada, and the St. Clair River (SCR), Michigan, USA. We subsequently developed RAD capture baits to genotype 3,446 RAD loci that contained 11,970 SNPs. Based on RAD capture assays, estimates of variance in SNP allele frequency among five Great Lakes tributary populations (mean FST 0.008; range 0.00–0.018) were concordant with previous microsatellite‐based studies; however, outlier loci were identified that contributed substantially to spatial population genetic structure. At finer scales within streams, simulations indicated that accuracy in genetic pedigree reconstruction was high when 200 or 500 independent loci were used, even in situations of high spawner abundance (e.g., 1,000 adults). Based on empirical collections of larval sea lamprey genotypes, we found that age‐1 and age‐2 families of full and half‐siblings were widely but nonrandomly distributed within stream reaches sampled. Using the genomic scale set of SNP loci developed in this study, biologists can rapidly genotype sea lamprey in non‐native and native ranges to investigate questions pertaining to population structuring and reproductive ecology at previously unattainable scales.

Scientific advances are needed to contend with invasive species. Trapping is often used for control or assessment, and understanding the invasive species’ behaviour is important for trapping success. A framework linking behaviour to trapping success and management responses was used to test hypotheses for the low trapping success of invasive sea lamprey (Petromyzon marinus) in the St. Marys River connecting Lakes Superior and Huron. Behaviour of sea lamprey approaching and at traps was quantified using external and internal tags and video. Multistate Markov models identified phenotypic and environmental factors influencing trapping success. Low trapping success for invasive sea lamprey in the St. Marys River is due to individuals not encountering traps, not entering upon encounter, not remaining at the trap, and not returning upon departure. All trapped lamprey were retained. Encounter with, and entrance into, traps varied with sea lamprey class, release date, and time of day, but not body length or river discharge. The conceptual and analytical methods applied here could be used to understand and improve trapping success for other invasive animals.

Physical removal (e.g., harvest via traps or nets) of mature individuals may be a cost-effective or socially acceptable alternative to chemical control strategies for invasive species, but requires knowledge of the spatial distribution of a population over time. We used acoustic telemetry to determine the current and possible future role of traps to control and assess invasive sea lampreys, Petromyzon marinus, in the St. Marys River, the connecting channel between Lake Superior and Lake Huron. Exploitation rates (i.e., fractions of an adult sea lamprey population removed by traps) at two upstream locations were compared among three years and two points of entry to the system. Telemetry receivers throughout the drainage allowed trap performance (exploitation rate) to be partitioned into two components: proportion of migrating sea lampreys that visited trap sites (availability) and proportion of available sea lampreys that were caught by traps (local trap efficiency). Estimated exploitation rates were well below those needed to provide population control in the absence of lampricides and were limited by availability and local trap efficiency. Local trap efficiency estimates for acoustic-tagged sea lampreys were lower than analogous estimates regularly obtained using traditional mark-recapture methods, suggesting that abundance had been previously underestimated. Results suggested major changes would be required to substantially increase catch, including improvements to existing traps, installation of new traps, or other modifications to attract and retain more sea lampreys. This case study also shows how bias associated with telemetry tags can be estimated and incorporated in models to improve inferences about parameters that are directly relevant to fishery management.

Invasive species can have detrimental impacts on native species and ecosystem services for humans. A technique that involves sterilization and release of males into wild populations of the same species can be useful in the control of invasive or pest species. A sterile‐male release technique (SMRT) was used on a novel vertebrate system, the invasive Sea Lamprey Petromyzon marinus in the Great Lakes, in an attempt to control population size. Sea Lamprey populations in the Great Lakes have been suppressed since the 1950s by (1) pesticide applications to kill larvae in streams and (2) barriers to block upstream spawning migrations. Here, we present a literature review and meta‐analysis of the SMRT by using a case study from the St. Marys River, where the SMRT was applied as an experimental method of Sea Lamprey control from 1991 to 2011. Observations obtained from the St. Marys River during and after SMRT application were used to evaluate whether the SMRT was effective at suppressing reproduction. Males were successfully sterilized and exhibited normal mating behaviors. The survival of embryos in nests was lower during the years when the SMRT was applied (32%) than during the post‐SMRT period (67%). The overall distribution of embryo viability in the river shifted after the SMRT was applied. During the SMRT application period, the observed ratios of sterile males to normal (fertile) males on nests were significantly different than expected, possibly due to an underestimation of adult Sea Lamprey abundance in the St. Marys River. Even at lower sterile male : normal male ratios, the number of viable embryos produced would have declined, but the level of reproductive suppression required to overcome recruitment variability was unclear. We discuss the effectiveness of the SMRT as it pertains to the Sea Lamprey, and we highlight difficulties in data interpretation and provide future direction for similar control programs. Received December 1, 2015; accepted June 16, 2016 Published online August 31, 2016