Is there a connection between rapid fluctuation in water temperature and cataract development in the Atlantic salmon (Salmo salar L)?

Cataract was diagnosed in Atlantic salmon (Salmo salar L) in sea water afte r a period of elevated surface water temperature with simultaneous rapid fl uctuation in water temperature measured at 15m depth. The affected fish wer e from four different hatcheries and had been released the preceding spring . Fish from each hatchery were kept in four different nets, and all nets we re affected, although not to the same extent. A possible relationship betwe en cataract and fluctuation in water temperatures is discussed.