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Preliminary assessment for the shrimp fisheries of the Negombo Lagoon (Sri Lanka).

Year of publication 2000

Place of publication Rome, Italy ;

Pages 98

Author Sanders, M; Jayawardena, A.; Ediriweera, S.

Product type Book (series)

Series title FAO Fisheries Circular

Series number 0429-9329 - C958

Edition 1

Synopsis (short abstract) The Negombo Lagoon has an area of 3 164 hectares and is situated some 40 km north of Colombo. It is part of a much larger Muthurawajawela Marsh-Negombo Lagoon coastal wetland. Apart from at the single narrow opening to the sea at its northern end, the water depth within the lagoon is less than 2 m. Six principal gears are used for catching shrimp inside the lagoon. Trammel nets are the most common, which along with cast nets are operated across the central portion of the lagoon. Stake nets are u sed immediately inside the entrance. Around the perimeter, lagoon seines (drag nets) and brush pile are the common gears. Fyke nets are also used at the southern end of the lagoon. Outside the lagoon, nonmechanized shrimp trawlers are operated north of the entrance, while mechanized shrimp trawlers are used 5 - 10 km to the south. The estimated catch from all gears operated inside the lagoon in 1997 was 613 t of shrimp and 1 044 t of others (mostly fish). The production from trawlers operated ou tside the lagoon was 270 t of shrimp and 239 t of others. Fourteen species of shrimp were identified, with six of these being major contributors to the catches. Penaeus indicus and to a lesser extent, P. semisulcatus were the most important in the trammel net and cast net catches. P. indicus was also the main species from brush piles. The stake nets set at the entrance caught mainly Metapenaeus dobsoni and M. moyebi. The latter were the major component of the catches with lagoon seines. The othe r important species caught in the lagoon was M. elegans. The main species in the trawl catches were M. dobsoni and Parapenaeopsis coromandelica. The former was the only major contributor to both the lagoon and outside catches. P. indicus and P. semisulcatus were relatively scarce in the trawl catches. Estimates of the growth and mortality parameters for each species are provided. Cash flow analyses are also reported in respect to base case fishing units for each gear type.......

Cite this content as:

Sanders, M.; Jayawardena, A.; Ediriweera, S.Preliminary assessment for the shrimp fisheries of the Negombo Lagoon (Sri Lanka).FAO Fisheries Circular. No. 958. Rome, FAO. 2000. 98p.

Language English

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