Demand for prawns is the cause of growing environmental degradation in poor countries where most farmed prawns originate, according to the Environmental Justice Foundation (EJF).
The UK-based charity, which campaigns on environmental and human rights issues, called for robust standards and labelling to avoid "long-term disaster for some of the world's poorest, marginalised coastal communities and for unique wildlife habitats"
It said that importers and retailers should raise their standards and show that their prawns, known often as shrimps, are not linked to what it said are widespread environmental problems. The EJF has produced a draft protocol on production.
"We are working with the major UK retailers to improve their standards of conduct," it said. "They are not as stringent as they could be."
Prawn farming often entails destruction of mangrove forests and other wetlands, pollution and use of harmful pesticides, antibiotics, fertilisers and disinfectants, said the EJF. It depletes wild fish stocks through loss of habitat, capture during prawn breeding and use of fishmeal by farmers.
The EJF said that in 2003, 1.72m tonnes of prawns worth £353m were imported into the UK, 38.7% of them from Asia and Oceania. World annual prawn production is worth $6.9bn (£4bn) at the farm gate and $50-60bn (£29bn-35bn) at the till. About a third is farmed, mostly in developing countries.
The EJF said prawn farms often have a working life of five to seven years before being abandoned.