4. Discussion
We successfully assigned \(\text{PS}_{i}\) values to 1,083 scat
collected from five different locations over the course of four
non-sequential years (Table S1, Figure 1) (Voelker et al. 2018). As
measured by repeated cross-sectional sampling and a specialization
metric (\(\text{PS}_{i}\)), the overall level of intrapopulation feeding
diversity in the region was high (\(\text{PS}_{i}\)= 0.399, 95% CI =
0.026, R = 100,000). Further, Month, Sex, and Location were all
important factors influencing this feeding diversity. Interestingly,
Month and Sex had a significant interaction. Habitat of an individual’s
primary prey also seemed to have an impact on relative specialization
suggesting that seasonal and sex-specific patterns in the use of benthic
vs pelagic were the underlying cause for the observed intrapopulation
feeding diversity. These indications of intrapopulation feeding
diversity suggest the feeding ecology of harbor seals in the Salish Sea
is complex and that prey species of concern may be impacted differently
by each sex.