A probe into the deaths of dozens of salmon and trout in one of Scotland's most famous fishing rivers has launched.

Since September 9, more than 50 adult fish have been discovered dead in a nearly 18-mile (29-kilometer) stretch of the Spey.

Alarming number of dead fish

The number of dead fish has alarmed Spey Fishery Board director Roger Knight.

He said that a few dead fish would be rather common at this time of year, perhaps six to twelve, but we have seen some quite troubling numbers.

"If it was just the odd dead fish being found we perhaps might not think that was anything unusual, but we suspect in excess of 50 dead adult fish have so far been found, and it could be more than that," he added.

Scottish officials are pressing for urgent action to contain the situation.

They underscored the seriousness of the reported dead fish and expressed concern about Scottish Environment Protection Agency (SEPA) lack of immediate action to address this.

"As soon as I was informed of this I was in touch with Sepa through parliamentary contacts and I'm urging them to treat this with the urgency it requires and outline what action they took when they were first notified," said Douglas Ross, Moray Member of Parliament.

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Suspected pollution

According to the Spey Fishery Board, pollutants could have killed the fish.

The SEPA stated that no evidence of recent pollution had been discovered, but that the issue was being monitored.

"Despite water sampling and ongoing inspections by officers, we've found no evidence of a pollution event that would have resulted in fish mortality on this scale," said David Ogilvie, Senior Manager for Environmental Performance at the SEPA. "We're continuingg to work closely with partners, including the Fish Health Inspectorate who lead on fish moralities."

They also carried out a visual inspection, looking for evidence of pollution, including discoloration, sewage fungus, foaming, and odor.

Aside from the dead fish, a child who went swimming in the River Spey near Aberlour at Carron and Laggan has since been reported to be sick.

In addition, anecdotal information suggests that a group of walkers and a dog were ill after drinking filtered water from the river near Aberlour.

The cause remains unknown.

The Fish Health Inspectorate collected samples from 19 deceased fish for testing. Meanwhile, SEPA has been testing the river to determine its water temperature and pH level.

Moray Council has stated that the issue has not affected the water supplies of its schools or any of its other facilities.

In the Indian River Lagoon, another fish death covered homeowners' backyards.

This fish kill occurred over the weekend in Indialantic, just over the Melbourne Causeway.

Long-time residents say they've never seen so many dead fish before, and they're concerned about the lagoon's water quality.

The tide had swept away many of the dead fish since their discovery, but there was still a strong smell of decomposition and swarms of insects.

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