Animal Justice says Marineland kept killer whale Kiska in "inadequate and unlawful" conditions.
An animal rights group is calling for charges against Marineland after the death of its last remaining orca.
Last week, killer whale Kiska died at the age of 47, after spending 40 years at the park.
The average lifespan of a killer whale is 50 to 90 years.
Officials say she had experienced failing health recently, however, an autopsy will be done.
The group Animal Justice has launched a petition to encourage provincial regulators to investigate and prosecute the park.
The group is also asking authorities to publicly release the results of her autopsy.
"Kiska deserves justice for what she endured", the group notes. "Animal Justice is calling on provincial authorities to make public the results of a post-mortem, and prosecute Marineland for the unlawful distress Kiska clearly experienced throughout her final years."
The death of Kiska, who was often referred to as "the world's loneliest orca", marks the end of orca captivity in Canada, as it is illegal to keep whales, porpoises and dolphins in captivity.
However, Marineland's current animals are exempt due to a "grandfather clause."
Recently, Marineland has lobbied the provincial government to sell the park.
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