Yield assessment for the small pelagics fishery occurring along the northwest, west and south coasts of Sri Lanka

摘要

This study utilized two separate approaches for assessing the current exploitation status for small pelagics in the northwest, west, and south coasts of Sri Lanka. In the first approach, modified Schaefer and Fox models were applied to a time series of annual catch (all species) and catch rate data. In the second approach, a length-based Thompson and Bell model was used with life history data for the trenched sardine (Amblygaster sirm.). This species comprises about 60% of the catches of small pelagics. The more convincing results were from the modified Fox and the Thompson and Bell models. The conclusion from these is that the small pelagics are not yet fully exploited, and that increased yields are possible. It is suggested (on theoretical grounds) that modest increases are unlikely to have negative impact on recruitment. This was not tested by analysis, nor was there an assessment of the socio-economic impact of increased exploitation. In view of these uncertainties, additional studies are required, along with continued monitoring of the fishery.