Azra Noonari, 39, was shocked to encounter pilfering behaviour from the wildlife at Woburn Safari Park, having had her own hubcaps stolen at home in Luton, Beds, just weeks beforehand.
She was with her six-year-old daughter and two-year-old son on a day trip to the Bedfordshire park in July, when the bizarre incident took place.
"I was driving us to the bear and wolf area when I saw a car stopped right in front of me," she said.
"There was a bear in front of it, so I stopped too and started taking pictures.
"I saw it take a hubcap off the car then start walking towards us. I locked all the doors quickly, we didn't know what it would do.
"It put the hubcap down and then banged on the window, as if it was trying to get my attention.
"It was almost like it wanted to give me the wheel cap."
Mrs Noonari said the strange situation came only weeks after all four of her own hubcaps were taken.
She added: "Maybe the bear thought I needed the hubcap.
"My little boy was crying but my daughter was enjoying it. She was saying, 'Oh my God mummy, look what he's doing'.
"Quite soon after a park warden came along and shooed the bear away.
"She asked me whose the hubcap was so it could be returned to the car in front.
"It was very strange, I don't know what the bear was doing.
"In a funny way I thought 'oh no, maybe even animals are starting to take hubcaps as well as people."
Male American black bears can grow up to 660lbs, with females reaching 180lb.
They are expert climbers but less aggressive than some other bear species and feed mainly on plants such as grasses, herbs, fruits, berries, honey, nuts and seeds.
They are the most common species of bears, although individual populations are at risk of isolation and starvation.