Staff from the Oamaru Blue Penguin Colony spotted the bird with a short bolt lodged behind its wing in Oamaru Harbour near Sumpter Wharf on Friday morning.
They were able to catch the gull, which was unable to fly, and take it to a local veterinary clinic.
The bolt was removed, and the bird was transported to the Dunedin Wildlife Hospital on Friday afternoon for specialist assessment and rehabilitation. The bird appears to be recovering well.
Red-billed gulls are a protected species under the Wildlife Act, and the maximum penalty for the disturbance of protected species is a fine of $100,000 and/or imprisonment for two years.
It's the second incident of red-billed gulls being shot in recent weeks – two gulls were found with blowdarts stuck in them in Waikanae in the last fortnight.
Department of Conservation (DOC) Technical Advisor ecology Bruce McKinlay says it is appalling that someone has shot the gull and DOC is taking the incident very seriously.
"If you have any information about this incident, we are asking you to come forward and share what you know with us.
"Though red-billed gulls may seem common, they have a threat classification of Nationally Vulnerable and their numbers are decreasing.
"We want to remind people that our protected and threatened species should not be used for target practice."
Oamaru Blue Penguin Colony science and environmental manager Philippa Agnew says it's unacceptable that the gull has been treated like this, and to do that to a living animal was incredibly cruel.
