Scordino et al.: Consumption of Oncorhynchus spp. by Zalophus californianus and Eumetopias jubatus in Washington 153 
Table 1 
Summary of the sampling of Steller sea lion (Humetopias jubatus) and California sea lion (Zalophus californianus) scat conducted 
by Scordino et al. (2022) from 2010 through 2013 in northwest Washington by year, season, and month. 
Spring 
Species Year Mar Apr May 
Steller sea lion 2010 
2011 
2012 
2013 
California sea lion 2010 
2011 
2012 
Summer Fall 
Winter 
Table 2 
Species-specific primers used to identify bones of Pacific salmon (Oncorhynchus spp.), found 
in scat of Steller sea lions (Eumetopias jubatus) and California sea lions (Zalophus 
californianus), to species by using real-time polymerase chain reactions. Scat samples were 
collected in northwest Washington from 2010 through 2013. Forward (F) and reverse (R) 
primers developed by Rasmussen Hellberg et al. (2010) and TaqMan minor groove binder 
probes were used. bp=base pair. 
Primer or 
Species probe 
Chum salmon 
Chinook salmon 
Pink salmon 
Steelhead 
Sockeye salmon 
Coho salmon 
SGAe VAT Vat Vase Vays VAS 
(O. clarkii) or bull trout (Salvelinus confluentus) because 
they are not common in the study area relative to other sal- 
monids (Brenkman and Corbett, 2005; Pearcy et al., 2018) 
and because a TaqMan MGB probe has not been developed 
for these species (Rasmussen Hellberg et al., 2010). 
An optimized multiplexed TaqMan presence-absence 
assay was performed in triplicate on all purified DNA 
samples by using an Applied Biosystems StepOnePlus 
Amplicon 
Sequence (5-3’) size 
TTGTCTGAGCTGTACTAATCACTG 104 bp 
AAGTGGTGTTTAAATTTCGATC 
VIC-CAACATAGTAATACCTGCTG-MGB 
GATAGTAGGCACCGCCCTIAGT 183 bp 
CCGATCATTAGGGGAATTAATCAGT 
NED-TCATAATCGGCATAACTAT-MGB 
TACGACCATTATCAACATAAAACCA 143 bp 
GGTCCGTGAGCAACATAGTG 
6FAM-CGGCAATCTCTCAGT-MGB 
ACCATTATTAACATAAAACCTCCAG 121 bp 
GTAATGCCTGCTGCCAGG 
VIC-CGTTTGAGCCGTGCTA-MGB 
GGAAACCTTGCCCACGCG 152 bp 
AAAAGTGGGGTCTGGTACTGAG 
6FAM-CTCTGTTGACTTAACCATC-MGB 
CGCTCTTCTAGGGGATGATC 95 bp 
CTCCGATCATAATCGGCATG 
VIC-ATTTACAACGTAATCGTC-MGB 
Real-Time PCR System (catalog no. 4876787, Thermo 
Fisher Scientific). Primer concentrations were 900 nM, and 
probe concentrations were 250 nM. Each run was accom- 
panied by internal positive and negative controls. Analysis 
was performed by using Applied Biosystems StepOne Real- 
Time PCR Software, vers. 2.0 (Thermo Fisher Scientific) 
built into the StepOnePlus Real-Time PCR System. This 
software was run by using a presence-absence setting that 
