A COMMENT ON TRANSFER EFFICIENCIES

This paper discusses the validity of several assumptions in a recent p ublication on the primary production required to sustain the annual wo rld fish catch of similar to 120 million t. A transfer efficiency betw een trophic levels in aquatic ecosystems of 15% results in the primary production requirement of 2.6% of the total primary production to sus tain the world fish catch, not 8% as reported from calculations with a transfer efficiency of 10%. The importance of accurate estimates of p redation efficiency and trophic level is shown.