Thousands of fish in the Dal Lake here have died over the past few days with authorities blaming a sudden fluctuation in temperature in the region.

Dal Lake dwellers expressed alarm over such large-scale fish deaths even as authorities said the occurrence was an annual affair.

"I received reports about the deaths of fish in Dal Lake yesterday. We sent a team to scout the lake for samples. We found that a lot of dead fish had collected around Centaur Hotel," Deputy Director Fisheries department Rafiq Ahmad told PTI.

"It seems that the fish have died due to sudden fluctuation in temperature. This is not unusual as it happens every year. You will find similar occurrences in other lakes like Manasbal (Lake) as well," Ahmad said.

It is an annual phenomenon which affects only one type of fish, the official claimed.

Asked if there can be any other contributing factors, Ahmad said pollution could also be a contributing factor as it changes the parameters of the water. "Coupled with temperature variation, it causes mortality among the fish," he said.

A senior inspector of the department has been asked to submit a detailed factual report ascertaining the cause of the fishes' death, he added.

However, lake dwellers, who live in houseboats in the lake, contradicted the official's claim saying they had never seen such large-scale fish deaths there.

"The reason for the deaths is the increase in the water level of the lake. The lake authorities have kept the water level up. Now, it has become a problem as the fish have died. It has caused a foul smell already and one cannot sit here," said Ghulam Mohammad, a Dal Lake dweller.

"A few fish would die earlier also but this is unprecedented. I have not seen this in 60 years of my life here," he added.

Some blamed the addition of chemicals to sewage water before it is released into the lake for the fish deaths.

"They put chemicals in these drains which has caused the deaths. These drains should be closed. This lake provides us with livelihood," said Bashir Ahmed, a fisherman for over 40 years at the lake. The fisherman also said he had not seen fish deaths of this scale in his lifetime.

Adil Ahmad, a frequent visitor to the lakeside, said the pollutants discharged from houseboats and waste material dumped into the lake was responsible for the situation.

"I think it is due to the sewage that comes out of houseboats. People should avoid polluting the lake. They should use dustbins which have been installed. I am a frequent visitor to the lake and I am seeing this for the first time that so many fish have died. I was shocked!" he added.

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