ENVIRONMENTAL VARIABILITY IN THE SOUTH EASTERN PACIFIC OCEAN OFF CHILE

Central South Fisheries

30°S

42°S

Central South Fisheries

Time

Space

DecadeInter-annualMonth Season YearDay

Ocean

Local

Regional

Basin Stock condition before ENSO

Adapted reproduction

Fishery pressure

Local Upwelling

ENSO strength and duration

Inter-decadal regime

Large scale forcing

Small scale fo

rcing

Mode of climate variability in the Mode of climate variability in the Pacific OceanPacific Ocean

Mantua et al. 1997. Bull.Amer.Soc.78:1069-1079.

LARGE SCALE FORCING

REGIME SHIFTREGIME SHIFT

Test de Ebbesmeyer et al.Test de Ebbesmeyer et al.

Hare y Mantua. 2000. Prog. Oceanogr. 47:103-146

1977 Regime shift

-1.0

-0.5

0.0

0.5

1.0

1965 1970 1975 1980 1985 1990

stan

dar

d d

evia

te

Annual Average

1977 Step

1989 Regime shift

-1.0

-0.5

0.0

0.5

1.0

1975 1980 1985 1990 1995 2000

stan

dar

d d

evia

te

Annual Average

1989 Step

RS RS

0

500

1000

1500

2000

2500

3000

3500

4000

4500

1965 1968 1971 1974 1977 1980 1983 1986 1989 1992 1995 1998 2001

YEAR

Lan

din

gs

(10

to

n)

Jack MackerelAnchovySardineHake

CHILEAN FISHERIES STATISTICS3

82- 83

97- 98

72 - 73

?

?

?

¿What are the requirements?

We need to manage basic population information, in order to predict changes in fish population stock. Therefore we need environmental data (long time series) to be included in stock assessment model.

ACTUAL WORK OBJECTIVES:

1. RETROSPECTIVE ANALYSIS: Identify pattern of environmental variability at diferents SCALES (time – space) and its possible relation with fish populations abundance fluctuations.

2. Identify existing methodology . 3. To maintain a long term monitoring program in the area, which allow

us to understand the consistency and strength of the detected relationship.

4. To identify new areas of interest that need additional research effort.

The first action is to identify the relationship between the environmental fluctuations with the annual recruitment changes, seeking to manage short term tools for predictions.

CASE OF STUDY

1.- Jack Mackarel

2.- Common Merluccius

3.- Hoki

4.- Common sardine

90 89 88 87 86 85 84 83 82 81 80 79 78 77 76 75 74 73 72

LONGITUD

42

41

40

39

38

37

36

35

34

33

32

31

30LA

TITU

D

42

41

40

39

38

37

36

35

34

33

32

31

30

Topocalma

Constitucion

Pta.Nugurne

Talcahuano

Pto.Lebu

Pto.Saavedra

Corral

Jack Mackarel spawning area

J. Mackarel Fish Ground

Sardine fishing ground

Common Sardine and Anchovy

-2.0

-1.5

-1.0

-0.5

0.0

0.5

1.0

1.5

2.0

82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 00 01 02 03

An

om

alía

TS

M (

°C)

TSM monthly average anomaly for period 1982-2003 for the coastal area of Central Chile 30°-40°S

-1.5

-1

-0.5

0

0.5

1

1.5

82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 00 01 02 03

An

om

alia

de

TS

M (

°C)

Promedio PromMov

SST Monthly Anomaly

Jack Mackarel Spawning area

Period: 1982 - 2003. Sector: 80°-90°W, 30°-40°S)