The FAO have published a report Preliminary Stock Assessment for the Shallow Water Shrimp Trawl Fishery of Tanzania based on catch and effort data for 1988. The report focuses on trawl fishing rather than farming, but it gives valuable indications in terms of times and conditions.
Issues related to the establishment of prawn farms in Tanzania, with an example from the Rufiji delta are available in this report published by the Mangrove Management Project, Forestry and Beekeeping Division of the Institute of Resource Assessment, University of Dar es Salaam.
A giant prawn farm to expropriate one third of the mangroves of the Rufiji Delta has recently been proposed by a private developer, the East African Fishing Company Limited, a subsidiary of TANNOL Holdings Ltd. Prawn farms have over the past 5 – 6 years been proposed for various locations along the Tanzanian coast, but none have so far been established.
This has generally been due to shortfalls in addressing social and environmental issues; issues often raised in Environmental Impact Assessments. The decisions not to approve projects have mostly been taken by funding or credit agencies and have rested upon experiences from similar projects in other countries where prawn farming has been practised in Asia and America. Both the positive and negative impacts of establishing large scale prawn farming are well documented in global literature.