1. . Assessment of the Icelandic cod stock Björn Ævarr Steinarsson Marine Research Institute

2. Components of advice (short-term) Data Data analysisAssess.Prediction Landings Length meas. Otoliths Surveys Catch in numbers Indices Stock assessment Predicted developm. of stock and catch Logbooks CPUE Otoliths Length m.

3. Input data Catch in numbers by age groups Survey indices Catch per unit effort (CPUE) from the fleet

4. Icelandic cod. Landings1906-1996

5. Cod Landings by gear

6. Distribution of cod catches

8. Sampling from landings Allocation –Samples alloced proportional to landings in each fleet category - Real time. Implementation –MRI staff –Inspectors from the Fisheries Directorate –The Coast Guard Magnitude –Annually about 150.000 length measurements and 15000 otoliths for ageing.

9. Cod Catch in number by age groups CV  20

10. Icelandic Groundfish Survey IGFS Annually about 600 fixed trawl stations taken in March all around Iceland since 1985. Performed by 4-5 identical trawlers Standarized trawl, trawling distance, trawling speed etc. About 50 000 length measured and 5 000 otoliths taken for ageing Gutted and ungutted weight, liver weight, gonad weight, stomach content anlysis, maturity etc.

11. IGFS Towing station in spring survey

12. IGFS - Primary objectives - Independent estimate of relative abundance. Annual indices of recruitment. Various biological parameters.

13. IGFS Total biomass index CV  10-16

14. IGFS Relative abundance index by age groups in 2002

15. Survey abundance vs number alive in the sea Number of fish of age a in survey Number of fish of age a in the sea

16. IGFS - COD Index of 3 years old vs. 4 years old a year later

17. Logbooks Example

18. Distribution of Logbooks records Bottom trawl Shrimp trawl Longline Capelin herring Dragnót Pelagic trawl Herring

19. Logbooks Objectives Collecting data to estimate CPUE/Effort Behavior of the fishing fleet Relationship with fishermen

20. CPUE vs Biomass CPUE (tonn/hour) Biomass (tonnes)

21. COD CPUE 1991-2001 by gears

22. Distribution of cod catches

23. Greenland Halibut Main fishing areas

24. COD Catch in numbers 1991-2000 (Millions) Yearclass 1988

25. COD IGFS index vs. VPA estimate of age group 6 97 96 95 94 93 92 91 90 89 88 87 86 85 R 2 = 0.8513 0 20 40 60 80 100 120 020406080100120 IGFS-Index VPA

26. COD Estimated 4+ biomass by different assessment models.

27. COD Probability plots of estimated fishable biomass in 2002-2005