Sample collection & genetic analysis
In 2016, a total of 1,520 upstream-migrating adult Yellowstone Cutthroat
Trout and 2,925 fry were sampled for genetic tissue. Overall genotype
success rates were very high, with 99.9% of adult samples (1,518) and
99.7% of the juvenile samples (2,917) successfully amplifying at 50%
or more of the SNP marker panel. Searches for duplicate genotypes
identified a total of 15 adult samples which were near exact matches
(>95% similar) of another sample, which likely represented
adults that passed above the weir, fell back, and were sampled again
when they reascended the weir. Duplicate searches among offspring
identified seven samples that were a duplicate of another. For both
adults and offspring, only one genotype was retained from each pair of
duplicates, whichever was the most complete (i.e., had the largest
number of alleles called). Parentage analysis assigned 2,310 (78.7% of
total number) of the fry samples to a parent-pair handled at the weir.