The incident comes days after a man was sentenced for bashing a gull to death and decapitating it in the Octagon because he believed it had tried to eat his food.
On Saturday evening, North East Valley resident Haydn Crawley said he heard a "commotion" outside the fish and chip shop on the corner of Islington St and North Rd, and a man screaming at two men, each about 20 years old.
He then saw one of the pair holding a red-billed gull by its wing before throwing it on the ground and attempting to "stomp on its head".
But he missed, breaking the bird’s leg and damaging its wing.
Mr Crawley ran over to scoop the injured bird off the ground, holding it against his chest, and confronted the pair with about four other bystanders.
"It's such a shocking thing to see people deliberately hurting an animal in front of you."
Bird Rescue Dunedin founder Sue Cook said she was contacted and took the gull to the Dunedin Wildlife Hospital to be assessed.
There should be harsher penalties for cruelties to the country’s wildlife and animal abuse seemed to be on the rise in the city, she said.
"It’s just happening too much in Dunedin with the seals and animal abuse."
Yesterday morning, a woman reportedly "tossed" a dead duck into Ross Creek after it was killed by a dog and Ms Cook said she had recently received several calls about off-leash dogs attacking wildlife in the area.
Carl Alan Michelle, 54, pleaded guilty to one charge of ill-treating an animal when he appeared in the Dunedin District Court on Thursday.
The court heard that on February 12, Michelle was sitting near the Robbie Burns statue in the Octagon when he grabbed a seagull and battered its head into a concrete seat, before pulling its head off and putting the dead bird in a rubbish bin.
A Department of Conservation spokeswoman said red-billed gulls were a protected species under the Wildlife Act.
Disturbing, injuring, or killing protected birds and destroying nests carried a maximum penalty of up to two years’ imprisonment, a fine of up to $100,000, or both, the spokeswoman said.
— People who witness anyone disturbing or harming protected wildlife should call 0800 DOC HOT (0800 362 468).
