Lucy, an Asian elephant, has been housed at Edmonton's Valley Zoo for 30 years. (CBC)

Edmonton's Valley Zoo has turned down an invitation to move its only elephant to a sanctuary in the United States.

Lucy is the only elephant in a Canadian zoo that lives on its own. Lucy has been on her own since September 2007, when the zoo's other elephant, Samantha, was moved to be part of a breeding program at a zoo in North Carolina.

Elephants are sociable animals, and many experts believe elephants are happier when they live with other members of their species.

Carol Buckley, director of the Elephant Sanctuary in Hohenwald, Tenn., offered to take Lucy so she has the opportunity to interact with other elephants. About 17 former zoo or circus elephants live on the sanctuary's 1,100 hectares of hills and forests.

"When she arrives, she has the opportunity to either immediately enter in with the herd or she can take her time and slowly get to know the other elephants," Buckley said.

"Each elephant is an individual and I will tell you of the 25 elephants we've rescued over the last 14 years, not one has been shy about making friends with other elephants.

"So we are very confident … Lucy would do the same thing and make friends immediately."

Zoo officials have turned down the invitation.

Lucy is happy interacting with humans, they said, and she also has health problems that could be aggravated by a move.

Lucy has a misplaced molar in her mouth that is pressing on her sinuses, said Milton Ness, the veterinarian at the Valley Zoo. Elephants normally breathe through their trunks, but Lucy's condition means she is now breathing completely through her mouth.

"There are some elephants out there that do best in a solitary environment because they've imprinted and bonded with their human keepers and Lucy is one that I know has done that," Ness said.

"Going into a multi-elephant environment in my mind is going to create more stress and with this respiratory problem, I'm very concerned that that would create a deteriorating health cycle."

Ness hopes the tooth will fall out on its own, but the zoo may try to take it out surgically

Buckley said Lucy's dental problems wouldn't be aggravated by a move.

"It's not that she's ill. She has a tooth problem, which is common in elephants, and it can be rectified," she said.

Valley Zoo officials think Lucy is fine where she is.

Staff look after her every day from 6 a.m. to 7 p.m. They keep her physically active by taking her for walks around the zoo grounds twice a day, and give her physiotherapy each day to help with her mild arthritis.

Treichel has spoken with Buckley from the Elephant Sanctuary and declined her offer to send an elephant veterinarian to Edmonton to look at Lucy's tooth problem.

Zoo officials regularly consult with animal experts in North America, Treichel said, and everyone they talk with agrees that Lucy should stay where she is.

With files from John Archer