A Pennsylvania man who credits an alligator named Wally for relieving his depression is searching for the reptile after it went missing during a vacation to Georgia in the United States. 

Joie Henney has thousands of social media users following his pages devoted to Wally, the cold-blooded companion that he calls his emotional support alligator.

He has posted photos and videos online of people petting the 1.7-metre alligator like a dog or hugging it like a teddy bear.

Wally's popularity soared to new heights last year when the gator was denied entry to a Philadelphia Phillies game.

Now, Mr Henney says he is distraught after Wally vanished while accompanying him on an April vacation in Brunswick, Georgia, a port city 112 kilometres south of Savannah.

He suspects someone stole Wally from the fenced, outdoor enclosure where the gator spent the night on April 21.

In social media posts, Mr Henney said pranksters left Wally outside the home of someone who called authorities, resulting in his alligator being trapped and released into the wild.

"We need all the help we can get to bring my baby back," Mr Henney said in a tearful video posted on TikTok. "Please, we need your help."

Mr Henney said he didn't have time to talk when The Associated Press reached him by phone on Wednesday morning. He did not immediately return follow-up messages.

The man from Jonestown, Pennsylvania, has previously said he obtained Wally in 2015 after the alligator was rescued in Florida at the age of 14 months.

Mr Henney told The Philadelphia Inquirer in 2019 that Wally helped alleviate depression following the deaths of several close friends.

He said a doctor treating his depression had endorsed Wally's status as his emotional support animal.