More than 25 tonnes of multiple species of fish were found dead on Sunday and Monday at Kampong Thom province’s Boeung Tonle Chhmar protected fishing reserve, apparently due to falling water levels and high temperatures.

Authorities looking into the issue attributed the deaths in Stoung district’s Peam Bang commune to shallow waters and extreme temperatures, according to Proem Ratha, former Stoung district governor and current Kampong Thom provincial administrative official.

Ratha told The Post on Monday that more and more fish have been dying since 2015 as Boeung Tonle Chhmar has become progressively shallower each year.

Authorities have announced a ban on fishing in the lake in an effort to preserve the remaining fish and protect rare species.

“My first conclusion is that the water was too shallow and the weather in our country at the moment is very hot. Also, over the past several days, there have been strong winds which may have worsened the problem.

“There was no rain, only strong winds, but there hasn’t been any polluted water flowing into the lake as there are no factories or other enterprises near here,” Ratha said.

Provincial Fisheries Administration director Pen Vanrith said he had received the information and was continuing to investigate why such a large number of fish have died.

His initial assessment matches Ratha’s – extreme temperatures heated up the shallow water causing the fish to perish.

Vanrith said fish die in the lake every year but in smaller numbers, with between five and six tonnes dying last year.

“The water at Boeung Tonle Chhmar has never completely dried up. It just always gets shallow in the dry season and the fish cannot bear the extreme hot weather.

“Most of the dead fish are white and have thin scales, and cannot survive in hot water,” he said.

Heng Leap, a villager from Stoung district’s Peam Bang commune, wrote on Facebook: “Fish have died in this protected area three times already. In the dry season the water is only 30cm deep.”

A Peam Bang commune official, who asked not to be named, identified the species of fish that died on Sunday and Monday. He said the dead fish, totalling 25.5 tonnes, comprised 12 tonnes of riel, three tonnes of chhpin, three tonnes of chra keng, two tonnes of chhlaing, two tonnes of khmann, two tonnes of krapat and sanday, a tonne of tra’on and half a tonne of ke sar.