Swan mortalities on the Grand Canal

Seventeen dead swans were recovered from the Grand Canal in Dublin  between the 9th and 10th of March and a further ten seriously ill swans removed from between Portobello Harbour and the Suir Road Bridge. Initially it was thought this was due to Avian flu but this has subsequently been ruled out with experts now believing the cause to be a bacterial disease, most likely botulism. However, what is of concern is that this is close to the area currently being dredged and that dead fish have also been reported. The dead animals are undergoing tests at the State Laboratory although confirmation of the cause of death is not expected until the end of the month. Swans are particularly vulnerable to sudden changes in water quality and contaminated food resources, especially in urban locations on canals where they do not find it easy to move from one enclosed stretch to another. In my opinion a possible link to the dredging activity does need to be positively ruled out so that this important maintenance work can continue in future years with any necessary safeguards in place.