1. Regional differences in Pacific sardine populations determined by otolith morphology Barbara Javor, SWFSC

2. Pacific sardine migrations Felix-Uraga et al., 2005

4. Humboldt Bay Monterey Pt Hueneme San Diego Ensenada Gulf of CA Bahía Magdalena Survey collections Port & bait samples

5. 1.Coastwide similarities and differences in juvenile otoliths (late age-0 to age-2) 2. Does temperature play a role? 3. Northern vs. Southern California vs. Ensenada: year-to-year trends 4. Offshore, adult sardine from spring surveys 4 Inter-related Otolith Research Studies

6. What can sardine otoliths tell us? Age Regional and temporal characteristics –Morphometric features [image analysis] –Temperature (  18 O in CaCO 3 ) [mass spec]

7. Collection of >5700 otoliths from most of their range Principal components analysis showed length, area, perimeter, and weight were the most important factors Analysis of “Perimeter-Weight Profiles” (PWP’s) based on weight-length, perimeter-length, and perimeter-area relationships of “average” otoliths Compared regions by age (size) and date Morphometric Analysis

8. Calculating perimeter from length or area

9. Calculating weight from length

10. Perimeter-weight profiles of sardine otoliths 1. Coastwide survey

11. There is a strong correlation between temperature vs. otolith perimeter and weight in the San Diego population of sardines 2. Temperature

12. PWP’s of age 0-1 cohorts, 2006-7: Monterey, Port Hueneme, and San Diego 3. Year-to-year trends

14. Nearshore sardines migrate away when they reach 170-180 mm SL

15. San Diego PWP’s appear to have shifted since 2008

16. Since July, 2008, San Diego sardine otoliths have had similar morphological characteristics as Gulf sardine

17. Both San Diego and Monterey sardine otoliths have had “warmer” PWP features since 2008

18. 96 Ensenada sardine otoliths are light and not highly lobed

19. Spring surveys, 2004 and 2009, Perimeter-Weight Profiles 4. Offshore adults

20. The relationship between otolith weight and standard length was uncoupled in offshore California sardine in 2004

21. Regional differences were found between Monterey, San Diego, and Baja California populations Age-0 otolith PWPs may resemble those of older sardine from the same locale and cohort Regional characteristics may change over time San Diego sardine since mid-2008 have had characteristics of southern Baja sardine. Why? Expansion of Baja populations, temperature preferences, oceanographic conditions? Conclusions from otolith morphology studies

22. Where do we go from here? 1.TRINATIONAL RESEARCH EFFORT: Sharing otoliths, methods, and data 2.FISHERMEN: Noting juvenile schools, special collections of young sardine 3.PORT SAMPLERS: Special set-asides of juveniles 4.STOCK ASSESSMENT TEAM: Is there a possible role for otolith attributes in models and predictions?

23. Acknowledgments Collaborators and co-authors at SWFSC Collectors at SWFSC, NWFSC, California Fish & Game, Fisheries & Oceans (Canada), CICESE & CICIMAR (Mexico) Everingham Bros. for monthly samples of live sardine

24. For further reading…