Task 3:Harmonization and the optimisation of the acoustic methodology

Involved participants: IFREMER, HCMR, CNR-Ancona, CNR-Sicily, IEO.

Introduction

• The acoustic target strength (TS) is an important metric in fisheries and plankton acoustics to inform on fish characteristics and to convert the acoustic energy in biomass units.

• TS = 20 log L + b20

• σbs = 10TS/10

Subtask 3.1.- Target strength equations for anchovy and sardine

WP objectives:1. To decide a common protocol for analysis.2. Literature review of existing TS equations

(Mediterranean and elsewhere) concerning sardine and anchovy.

3. To apply different TS equations in past acoustic data from each area and comparisons of the resulting abundant estimates will be made.

4. To estimate in situ TS equations for each target species (2002-2006).

1.- To decide a common protocol for analysis.

• To apply the same TS (sardine & anchovy) to all the Mediterranean acoustic surveys?

• To estimate sardine (Sardina pilchardus) and anchovy (Engraulis encrasicolus) TS “in situ” in every area (Adriatic, WMed; EMed…) and to apply each one to its respective area…?

b20 PIL ANEIFREMER -71.2 -71.2IEO -72.6 -72.6/-71.2IPIMAR -72.6 -71.2AZTI -72.6 -72.6

-71.2 dB (Diner & Marchand, 1995; ICES 1997)-72.6 dB (Degnbol et al., 1985) (Herring, Clupea harengus)

2.- Literature review of existing TS equations (Mediterranean and elsewhere) concerning

sardine and anchovy.

b20 PIL ANEIFREMER -71.2 -71.2IEO -72.6 -72.6IPIMAR -72.6 -72.6AZTI -72.6 -72.6

-71.2 dB (Diner & Marchand, 1995; ICES 1997)-72.6 dB (Degnbol et al., 1985) (Herring, Clupea harengus)

2.- Literature review of existing TS equations (Mediterranean and elsewhere) concerning

sardine and anchovy.

2.- Literature review of existing TS equations (Mediterranean and elsewhere) concerning

sardine and anchovy.

b20 PIL ANE

HCMR -72.6 -71.2

IFREMER -71.2 -71.2

SICILIA -70.51 -75.3

ANCONA -72.5 -74.6

IEO -72.6 -72.6

2.- Literature review of existing TS equations (Mediterranean and elsewhere) concerning

sardine and anchovy.

b20 PIL ANE

HCMR -72.6 -71.2

IFREMER -71.2 -71.2

IAMC -70.51 -75.3

ISMAR -72.5 -74.6

IEO -72.6 -72.6

2.- Literature review of existing TS equations (Mediterranean and elsewhere) concerning

sardine and anchovy.

b20 PIL ANE

HCMR -72.6 -71.2

IFREMER -71.2 -71.2

SICILIA -70.51 -75.3

ANCONA -72.5 -74.6

IEO -72.6 -72.6

2.1 dB 4.1 dB

Barange et al., 1996; PIL (Sardinops ocellatus): -70.51; ANE (Engraulis capensis/encrasicolus): -76.1 (South Africa)

3.- To apply different TS equations in past acoustic data from each area and comparisons of the resulting abundant estimates will be made.

Abundance Biomass

TS= -72.6 TS= -71.2 dif (%) TS= -72.6 TS= -71.2 dif (%)

Anchovy205255882

0165606733

3 -19.32 28801 23246 -19.29

Sardine211076814

1199160932

6 -5.65 73336 69855 -4.75

S. colias 553530499 514426034 -7.06 52440 49222 -6.14

TOTAL471685746

0416210269

3 -11.76 154577,39 142322,67 -7.93

Relative Abundance (%) Relative Biomass (%)TS= -72.6 TS= -71.2 dif (%) TS= -72.6 TS= -71.2 dif (%)

Anchovy 43,52 39,79 -3,73 18,63 16,33 -2,30

Sardine 44,75 47,85 3,10 47,44 49,08 1,64

S. colias 11,74 12,36 0,62 33,92 34,58 0,66

100 100 100 100

EcoCádiz 2004: TS anchovy = -72.6, TS sardine = -72.6, TS S. colias = -68.7EcoCádiz 2004R: TS anchovy = -71.2, TS sardine = -72.6, TS S. colias = -68.7

3.- To apply different TS equations in past acoustic data from each area and comparisons of the resulting abundant estimates will be made.

4.- To estimate in situ TS equations for each target species (2002-2006).

• Fishing hauls selection:– Frequency: 38 kHz.– At nigth, dispersed.– High percentage of one species, 70, 80, 90%?– Other species? Different length distribution.– Better not bimodal.– Echosounder performance? (Soule et al, 1995; Jech et al,

– In situ target strength measurements. Preliminary data of sardine (Sardina pilchardusW.) from the Mediterranean Sea. 1993. Carrera, P., J. Miquel & M. Iglesias. Working paper. ICES FAST Working Group. Gothenburg, April 21-22.

Fishing trawls with species percentage = or > to 87%  

Año Especie 90 91 92 93 95 96 97 98 99 00 01 03 04 05 06 07 08 Total S. pilchardus 4 8 3 6 6 8 5 6 8 5 5 2 1 3 1 1 72 E. encrasicolus 4 2 1 1 3 2 1 3 6 5 1 1 4 34 S. aurita 4 1 1 1 1 1 9 B. boops 1 3 1 5 S. colias 3 3 T. mediterraneus 1 1 2 Total 12 10 4 7 10 10 8 10 11 5 14 10 2 3 2 1 6 125

ECOMED 1990-2008

Fishing trawls with species percentage = or > to 87%  

Cuenta de Porcentaje

Año

Campaña Especie 90 91

92

93

95

96

97

98

99

00

01

02

03

04

05

06

07

08

Total

ECOCADIZ E. encras 1 13 9 23

S. colias 2 1 3 6

S. pilchardus 3 3

T. picturatus 1 1

Total ECOCADIZ 3 18

12 33

ECOMED S. pilchardus 4 8 3 6 6 8 5 6 8 5 5 2 1 3 1 1 72

E. encras 4 2 1 1 3 2 1 3 6 5 1 1 4 34 S. aurita 4 1 1 1 1 1 9 B. boops 1 3 1 5 S. colias 3 3 T. medit 1 1 2

Total ECOMED 12 10 4 7

10

10 8

10

11 5

14

10 2 3 2 1 6 125

PELACUS S. pilchardus 1 3 4 4 6 9 7 3 4 41

S. scombrus 2 4 6 2 5 2 3 1 2 27

T. trachurus 3 2 1 4 5 2 1 18

B. boops 2 1 2 2 2 9

M. poutassou 3 2 1 2 8

E. encras 2 2 4 C. aper 2 1 3 S. colias 1 1 2

T. picturatus 1 1

Total PELACUS 6 9 12

12

16

19

20 9

10 113

Total general 12 10 4 7

10

10 8

10

11

11

23

12

22

21

22

40

22

16 271

Green: raw data from EK60 (SIMRAD)

PESMA software

PESMA software