Footage shot by the People for the Ethical Treatment of Animals has exposed the cruel treatment of owls on display at the Harry Potter Warner Bros Studio tour in Hertfordshire.
The footage shows the owls kept in tiny cages or tethered to perches as a man who handles the owls tells visitors they stay on display all day before being returned to cages.
Peta’s Yvonne Taylor, told the Mirror she had written a letter to Warner Brothers informing them of their trainers' "gross negligence" in handling the birds and encouraging flash photography.
"Owls have especially acute vision and find blinding camera flashes extremely distressing – this can be seen in Peta’s footage as they respond by desperately chewing at their tethers and shaking their heads," she wrote.
Despite signs warning tourists not to touch the birds, the handlers can be heard and seen encouraging visitors to stroke the owls.
"As experts will tell you, as well as being stressful for the owls, this also interferes with the natural oils in their feathers that keep them warm," Ms Taylor told the Mirror.
Approached for comment, a tour spokeswoman told the Mirror the owls’ “welfare is of paramount importance to us".
J.K. Rowling, author of the Potter book series, has previously spoken out for the welfare of owls when it was suggested her readers may be tempted by her books to buy owls as pets.
“If anybody has been influenced by my books to think an owl would be happiest shut in a small cage and kept in a house," she said, "I would like to say as forcefully as I can, ‘You are wrong’.”