Inland fisheries resources and the current status of aquaculture in Sri Lanka

The aim of this working paper was to evaluate the potential of different fisheries enhancement and aquacultural systems to benefit marginal farmers who manage small rainfed irrigation systems in the lowland Dry zone of Sri Lanka. Analysis was based on secondary data and key informant interviews with professional fishermen and marginal farmers in N.W Province. [PDF contains 57 pages]

On the behaviour of marine crustaceans in an electrical field of alternating current

The minimum flow of current essential to produce electro-narcosis and fixation in marine crustaceans, Metapenaeus affinis, Parapenaeopsis stylifera, Panulirus ornatus and Neptunus sanguinofentus in an AC field of specific strength varied with the lengths of animals tested, except in case of the last one where the increase in size of animals showed no significant effect on the effective period for different reactions. M. affinis in interrupted AC required threshold pulses for narcosis and fixation, which varied inversely with the length of the organism. Animals subjected to current of higher effective period required longer time for recovery in interrupted AC of 50 c/s. The period for narcosis and recovery of M. affinis did not vary significantly with repeated stimulations on the same organism.