Locals living near Martinwells Lake in Doncaster, Yorkshire, had recently noticed that the duck population had diminished significantly. Fishermen also realized that fish stock was lower than usual.
Soon after, fishermen literally caught the answer to the mystery: Two piranhas.
Piranhas are native to South America, but sometimes find their way to Europe, where people keep them as ‘pets’.
One theory is that the piranhas grew too large for their tank and the owner simply dumped them into the lake, where they have been running amok and devouring ducks and fish.