The gull was brought to the Dunedin Wildlife Hospital a day after two 20-year-old men were seen attacking it outside a fish and chip shop on the corner of Islington St and North Rd last month.
At the time of the attack North East Valley resident Haydn Crawley said he saw one of the men holding a red-billed gull by its wing before throwing it on the ground and attempting to "stomp on its head".
Hospital Trust manager Jordana Whyte said it was unconscionable anyone could treat an animal that way.
"I can’t believe that anybody would behave that way and be so disgusting and violent towards a creature that's just minding its own business.
"It’s all completely and totally unnecessary."
The attackers should be "ashamed and embarrassed".
The gull had received "very serious injuries" by being kicked or stomped.
Ms Whyte said the gull was "extremely lucky" that Mr Crawley had intervened and stopped the attack just in time.
"If they kept going the way they did the gull would have been killed pretty quickly.
"Obviously the people had gotten in some pretty good whacks before they were stopped."
"We’re really happy we could help it and get it better."
Ms Whyte asked anyone with information about the attack to get in touch with the police.
"We can’t just tolerate it, it’s not acceptable."
She said people tended to treat red-billed gulls like vermin and put them on the same level as an introduced pest.
The gulls were actually native to New Zealand and a threatened species.
The attack took place days after a Dunedin man Carl Alan Michelle was sentenced for bashing a gull to death and decapitating it in the Octagon because he believed it had tried to eat his food when he was intoxicated.
He was convicted and ordered to donate $2000 to the Dunedin Wildlife Hospital.
Ms Whyte said the "reparations" Michelle received were not enough.
"That's obviously not enough to deter people like this from from doing it."
The maximum penalty for the charge is five years’ prison and a $100,000 fine.
