Over 80 'Frankenfish' caught swimming up Susquehanna, tried passing through Conowingo Dam

Some 81 northern snakeheads, also dubbed “Frankenfish”, attempted to swim up the Susquehanna River and through the Conowingo Dam during the spring migration season, according to the Baltimore Sun.

This is reportedly a dramatic increase since only one snakehead was observed passing through a designed fish lift the past two seasons.

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Native to Asia, the northern snakehead splashed on to the scene in Pennsylvania in 2004 when some were discovered in Philadelphia County. Snakeheads are considered a delicacy and are brought to the United States as potential meals and/or pets.

Given their aggressive nature, northern snakeheads pose numerous threats to native Pennsylvania fish. They are one of the few species that will protect a brood from other fish in order to protect and ensure the survival of the young.

The 81 fish discovered this spring were caught before they made it upstream. Upon being observed in the dam’s western fish lift, they were removed and euthanized.

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