SeaWorld's market CAP now sits at 1.57 billion - down from $3.26 billion on August 2013.
Wednesday's dip was in tandem with the rest of the stock market, which took major hits across the board amid anxiety over the slowing economy, lackluster corporate earnings and fears of the spreading Ebola virus.
"I love to see SeaWorld stock tank, but not with the rest of the market," Louie Psihoyos, Executive Director of the Oceanic Preservation Society, told The Dodo. "Hopefully their stock will lay at the bottom with other poor stock performers when the economy bounces back."
But SeaWorld's recent financial nosedive can't be entirely blamed on the the market slump. In August, the company's stock fell by nearly a third after it finally admitted that the documentary "Blackfish" and the controversy over its orca whale care had hurt attendance at its parks.
A graph of SEAS over the past three months shows the huge drop: