Toni Frohoff with In Defense of Animals says the designation is reserved for zoos that refuse to make changes within a reasonable time that would benefit their elephants.
Various animal rights groups have been after the Edmonton zoo for years to move Lucy.
They say Edmonton's winter is too harsh for the elephant.
The zoo says Lucy has been examined by a veterinarian and deemed too sick to travel because of respiratory troubles.
Frohoff says the Valley Zoo has been on her California-based group's annual Top 10 list of worst zoos four times.
It was second last year, but escaped the list this year, although Frohoff says the "Hall of Shame" status is even worse.
“Unfortunately the Edmonton Valley Zoo has earned that dishonourable distinction. They have the opportunity to be heroes, but instead they are choosing to be villains by allowing Lucy to stay,” she said.
“Other elephant experts, some of them extremely notable, have denounced the Edmonton Valley Zoo as creating amongst the most cruel ... environments for elephants in zoos.”
In Defense of Animals is calling on city council to make a change.
The Calgary and Toronto zoos no longer have any elephants after moving them to warmer climates in the United States.
(CHED, The Canadian Press)
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