Aglen et al_Retrospective review.pdf (132.8Kb)

Retrospective review of management advice for Northeast Arctic cod

Aglen, A.

Nakken, O.

Yaragina, N.

Sokolov, K.

PINRO, Murmansk, Russia

IMR, Bergen, Norway

Brief history of the NEA cod fishery regulation measures

Year Year Fishery regulation measures Fishery regulation measures

1946 Introducing minimal mesh size in trawls of 80/90 mm 1961 Introducing minimal mesh size in trawls of 110 mm

1963 Introducing minimal mesh size in trawls of 120/130 mm 1978 Establishing annual TAC for trawl fishery

1979 Introducing measures to improve spawning conditions

1983 Establishing annual TAC (for all fishing gears)

1981 Introducing minimal mesh size in trawls of 125 mm 1982 Introducing minimal mesh size in trawls of 135 mm*

1984 Limiting the by-catch of juvenile Gadidae on shrimp fishery 1992 Limiting the by-catch of juvenile Gadidae on capelin fishery 1993 Introducing sorting grids on shrimp fishery

1997 Introducing sorting grids on cod fishery

* - applied to all vessels operating in Norwegian economic zone

Scheme of Northeast Arctic cod management advices elaboration

Advice on fishery management Advice on fishery management

Conceptual basis Criteria of

Reference points Conceptual basis

Criteria of Reference points

Stock assessment

Stock assessment Mathematical methodsMathematical methods

Fisheries statistics

Fisheries statistics SurveysSurveys Monitoring of biological status

Monitoring of biological status

Catch by the ICES

areas Catch by the ICES

areas

Length / age distribution

of catch Length / age

distribution of catch

Indices of abundance Indices of

abundance Length /

weight at age in

stock Length / weight at

age in stock

Stomach data Stomach

data

Mean weight at age in catch Mean weight

at age in catch CPUECPUE Maturity ogives Maturity

ogives ConditionCondition

Material and methods

All data are taken from the annual ICES reports (ACFM reports;

NEA cod section).

There are comparison of results borrowed from:

a. Annual assessments taken in previous years;

b. Updated annual assessments taken in final year (2005).

Catch of NEA cod in 1984-2005, ‘000 t

0 200 400 600 800 1000

1983 1985 1987 1989 1991 1993 1995 1997 1999 2001 2003 2005

Catch, '000 t

Adviced Agreed Actual

Spawning stock biomass (A.) and fishing mortality (B.) of NEA cod in 1984-2005

0 200 400 600 800 1000 1200

1983 1988 1993 1998 2003

SSB, '000 t

0,0 0,2 0,4 0,6 0,8 1,0 1,2

1983 1985 1987 1989 1991 1993 1995 1997 1999 2001 2003 2005

Fishing mortality (5-10)

Annually 2005

A.

B.

1984- 1986

1991-

1997

Recruitment of NEA cod at age 3 in 1984-2005, 10 ⁶ spec.

0 200 400 600 800 1000 1200

1983 1985 1987 1989 1991 1993 1995 1997 1999 2001 2003 2005

Recruitment, 106

Annually 2005

Consequences for future management advices

• Unification of fishery management rules within the margins of cod area;

• Receiving reliable fishery statistics;

• Improving stock survey’s methodology;

• Minimizing uncertainties related to assessment

methods and data.