By Alex DeMetrick

BALTIMORE (WJZ)– Thousands of dead fish have ended up in Baltimore’s Inner Harbor, and experts still aren’t sure why.

“We got first reports on Friday afternoon around–between Key Bridge and Fort McHenry, and by Saturday it spread to the Lighthouse Point Marina near Canton,” according to Blue Water Baltimore’s Waterkeeper Angela Haren.

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Maryland’s Department of Environment estimates as many as 30,000 fish died, nearly all of them Atlantic menhaden. In the past, fish kills have been triggered by algae blooms, which use up all the dissolved oxygen in the water, but not this time.

“We’re still doing testing,” Haren said. “At this point, it looks like there’s no harmful algae bloom.”

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MDE has also been testing the water and can find no pollution source that would cause a fish kill, which brings the focus onto the menhaden themselves.

“Because most of the species affected are just one type of fish, that leads us to believe it might be some type of disease, but again we’re still investigating,” Haren said.

Birds have already removed most of the fish from the harbor.

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