Measuring a cockle during the research (IMAGE) Swansea University Caption The data showed that cockle sizes declined in the late 1990s, and modernisation of wastewater treatment was significantly related with this downward trend, suggesting that the changed nutrient regime in the estuary may have resulted in reduced food provision for cockles Credit Ruth Callaway, Swansea University Usage Restrictions Use only with credit as below License Original content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.