FAO Fisheries Report No. 618
Report of the________________________________ WORKSHOP ON THE SMALL PELAGIC RESOURCES OF ANGOLA, CONGO AND GABON Luanda, Angola, 3-7 November 1997
FIRM/SAFR/R618(En) ISSN 0429-9337
- 146 REPORT OF WORKING GROUP 7 ETHMALOSA FIMBRIATA
Participants : J. Doumambila-Bantsantsa, R. Mbokou, L. Maloueki A. Miguel De Sousa, P. Freon OBJECTIVES
The objective of this working group was to review the present knowledge on the biology, exploitation and assessment of Ethmalosa fimbriata in the three countries (Gabon, Congo and Angola). INTRODUCTION
Ethmalosa fimbriata is named “ sardine ” in Gabon, “ manzi ” in Congo and “savelha” in Angola. Despite the fact that it is a secondary species in the area (except in Gabon where it represents 30 to 40% of the total catch), it is an important species for the small-scale fisheries and for the coastal populations who consume it fresh or smoked. DATA
Few data are available on this species. Catches
Gabon: three areas were identified and the corresponding catches in 1996 were: Estuaire (Estuarine area in front of the Komo river): Ogooue maritime (river mouth of the Ogooue river): Nyanga (river mouth of the Nyanga river, near Congo: Total catch:
12 245 t 668 t 25 t 12 938 t
The statistical monitoring of catches was initiated by a FAO project (Dbase, ARTFISH and ARTSER software) in 1992 and ended in 1996, but data collection is still going on. Congo: : statistical data have been collected regularly at the main landing sites since 1981 through a joint project between DGP (Direction des Pêches Maritime du Congo) and ORSTOM. An example of the results obtained is presented below.
Year
Orstom (t) 1989 1990 1991 1992
26 14 50 40
Landing points Cercle Matombi Pointe naval (t) (t) indienne (t) 72 163 7 22 86 0 33 335 0 24 292 0
Total (t) 268 122 418 356
- 147 Secondary landing sites are located in Conkouati (near the Conkouati lagoon) and in M’vandji (near the Noumbi river mouth). The main seasons of fishing are the “long warm season” (January to April) and the “short warm season” (October to November). Angola: the species is present in coastal areas, near river mouths, but it seems not significant in the industrial catches and is therefore not identified. From April 1996 to March 1997, a survey of the small-scale fishery was implemented in co-operation with the French mission of co-operation all along the coast. The catches were estimated at 1 759 tons during 12 months and constituted 3.8% of the total catch. Presently no length frequency data are available for this species in any of the three countries. Gears
In the three countries, artisanal fisheries using mainly circling gill nets catch Ethmalosa. Beach seines are also used to catch the species but to a lesser extent. Cast nets are also used for catching juveniles. The main difference in gear between Gabon and Congo is the mesh size of the circling gill nets. In Gabon the mesh size was smaller for Ethmalosa than for sardinella, resulting in catches of young fish. In consequence, the Gabonese government prohibited the use of small mesh sizes and of beach seines in 1997. In contrast, Congolese fishermen use a larger mesh size for Ethmalosa than for sardinella, a practice that is common in West Africa due to the greater depth of the body of the former species. Biology
Until now, no biological studies have been carried on in the area. Nevertheless, from studies in other countries (Ghana, Ivory Coast, Gambia and Senegal) this species is known to be tolerant of low salinity and to have part of its life cycle in brackish waters. Adults can spawn either in rivers (salinity > 5 psu1) or in coastal areas.
1
psu = Practical-Salinity Unit
