1. MEDIAS A protocol for acoustic surveys in Mediterranean sea
History
Acoustic surveys are performed by each country around the Mediterranean basin. There is a need to harmonize the protocol of these surveys for further comparisons of the results issued from different areas.
Objective
Adopt a common Protocol for a Pan-Mediterranean Acoustic survey (MEDIAS) within the Framework of the DCR according to the recommendation of RCM for Mediterranean and the decision of the Liaison Meeting
Palma de Majorque 22-24/11/2010

2. Small pelagics in the Gulf of Lion
Jlb : Hello
Small pelagics in the Gulf of Lion
Total small pelagic species biomass fluctuates a lot between 1993 and 2010 with the highest level in 2005 with more than tons
Protocol of acoustic survey is the same since 1993 and follows Medias one
Pelagic species assessed are :
Anchovy and sardine in first priority
Other one’s if present in the area
Palma de Majorque 22-24/11/2010

3. N/O L’EUROPE - Survey PELMED

4. GSA 07 Gulf of Lion The surface of Gulf of Lion is 3300 Nm²
We did acoustic survey in july with L’Europe (30m) at 8 knots on parallel transects from depth 10 m to 200 m.
Transects spaced 12 Nm. EDSU=1Nm
We did survey and hauls in day time during 26 days
2 hauls used (Vo 15 m and 7 m, 12 mm of mesh side)
Sounder ER60 38, 70, 120 and 200 KHz. Data format .hac
Threshold for acquisition : -80 db
Threshold for assessment : -60 db
Pulse duration : 1024 µs
1 calibration during the survey
Palma de Majorque 22-24/11/2010

6. Pelmed08 - July

7. Pelmed09 - July

8. Pelmed10 - July

9. Type d’opération
Nombre
Remarques
Milles parcourus en acquisition acoustique
2176
Movies+ ER60 (38, 70, 120 kHz et 200 kHz), EK KHz
Chalutages pélagiques 4PM159 38
Chalutages de fond 4FF176 5
Par sonde inférieure à 40 m
CTD 47
Profils bathymétriques (T°C, S‰, P)
T°C et S‰
Enregistrement continu en sub-surface durant 2176 Mn
Prélèvement d'otolithes d'anchois
200
Congélation d’anchois issus de 13 chalutages
Prélèvement d'otolithes de sardine
Inclusion d'otolithes issus de 13 chalutages
Biométrie de merlu
300
de 10 à 46 cm, pour lecture des otolithes. Action MERLUMED

13. Small pelagics stock assessment
Estimated biomass for 2009 and 2010
Anchovy : and tonnes
Sardine : and tonnes
Low level of sardine biomass after the peak of 2005
Anchovy biomass increase after 4 years of stability
Palma de Majorque 22-24/11/2010

15. Pelmed survey in the gulf of Lion
Length and age structure for anchovy
Years 2000 to 2010

18. Pelmed survey in the gulf of Lion
Length structure for sardine
Years 2000 to 2010

19. Thank you for your attention