Scores of fish are turning up dead in Lake Karla, central Greece, it was revealed yesterday, as officials cited the sharp drop in temperatures as a possible reason for the deaths. It is the third time this year that Lake Karla, a once-drained lake that was recently restored to irrigate the Thessaly Plain, has been hit by the phenomenon, also known as «fish kill.» Some locals said the fish were floating amid foam and debris. But Natassa Economou, Magnesia’s vice prefect, yesterday told Kathimerini that the incident was caused by the rapid drop in temperature. Tests on the fish and water have so far reportedly shown that oxygen levels in the lake were normal. «We have been monitoring the quality of the lake water since September 2009 and only once, in early 2010, did we find high ammonia levels as a result of pollution from fertilizer use on nearby farmland,» Economou said. A second fish kill in September was caused by low water levels, she added.