1625Adult genotypes by year01-10Adult data captured in 10 years (2001-2010). Each year data include passive integrated transponder (PIT) tags, annual adult ID, sampling date, and genotypes based on 12 microsatelitte loci.2001offspringgenotypesData include ID and 12 microsatelitte loci genotypes of juveniles collected in 2001. BLJ1-, BLJ2-, and BLJ3- represent juveniles collected at Black Lake in the first, second and third runs, repsectively.2002offspringgenotypesData include ID (BLJ) and 12 microsatelitte loci genotypes of juveniles collected in 2002.2003offspringgenotypesData include ID and 12 microsatelitte loci genotypes of juveniles collected in 2003. IDs were marked as BLJ-, DF-, and DM-. BLJs represent juveniles that were collected during their drifting downstream at Upper Black Lake river, DF- and DM- live and dead juveniles that were collected and reared in a streamside hatchery for three months before being released to the river.2004offspringgenotypesData include ID and 12 microsatelitte loci genotypes of juveniles collected in 2004. IDs were marked as DF-, and DM- which represent live and dead juveniles, respecitively, which were collected and reared in a streamside hatchery for three months before being released to the river.2005offspringgenotypesData include ID and 12 microsatelitte loci genotypes of juveniles collected in 2005. IDs were marked as BDF-, BDM-, WDF-, and WDM-. DF and DM represent live and dead juveniles, respecitively, which were collected and reared in streamside hatcheries (B: Black Lake hatchery; W: Wolf Lake hatchery) for three months before being released to the river.2006offspringgenotypesData include ID and 12 microsatelitte loci genotypes of juveniles collected in 2006. IDs were marked as BDF-, BDM-, WDF-, WDM-, DF-, and DM-. DF and DM represent live and dead juveniles, respecitively. B and W represent streamside Black Lake and Wolf Lake hatcheries where juveniles were reared for three months before being released to the river. DF-, and DM- without B or D are live and dead juveniles that were collected during their drifting downstream at Upper Black Lake river.2007offspringgenotypesData include ID and 12 microsatelitte loci genotypes of juveniles collected in 2007. IDs were marked as DF-, and DM- which represent live and dead juveniles, respecitively, which were collected and reared in a streamside hatchery (Black Lake hatchery) for three months before being released to the river.

Quantifying interannual variation in effective adult breeding number (Nb) and relationships between Nb, effective population size (Ne), adult census size (N) and population demographic characteristics are important to predict genetic changes in populations of conservation concern. Such relationships are rarely available for long-lived iteroparous species like lake sturgeon (Acipenser fulvescens). We estimated annual Nb and generational Ne using genotypes from 12 microsatellite loci for lake sturgeon adults (n = 796) captured during ten spawning seasons and offspring (n = 3925) collected during larval dispersal in a closed population over 8 years. Inbreeding and variance Nb estimated using mean and variance in individual reproductive success derived from genetically identified parentage and using linkage disequilibrium (LD) were similar within and among years (interannual range of Nb across estimators: 41–205). Variance in reproductive success and unequal sex ratios reduced Nb relative to N on average 36.8% and 16.3%, respectively. Interannual variation in Nb/N ratios (0.27–0.86) resulted from stable N and low standardized variance in reproductive success due to high proportions of adults breeding and the species' polygamous mating system, despite a 40-fold difference in annual larval production across years (437–16 417). Results indicated environmental conditions and features of the species' reproductive ecology interact to affect demographic parameters and Nb/N. Estimates of Ne based on three single-sample estimators, including LD, approximate Bayesian computation and sibship assignment, were similar to annual estimates of Nb. Findings have important implications concerning applications of genetic monitoring in conservation planning for lake sturgeon and other species with similar life histories and mating systems.