Access to harbour basin wharves could be denied to fishers if they "blatantly endanger'' themselves and others by not obeying Port Otago signs.
Port Otago chief executive Geoff Plunket said several people were fishing near the T/U sheds on Victoria Wharf on Thursday despite heavy machinery operating in the area.
The fishers had ignored the signs prohibiting public access and driven on to the wharf.
Parking cars too close to where cargo loaders, cranes and trucks were working put the fishers, Port Otago staff and the general public in danger, Mr Plunket said.
"Port Otago has to be able to guarantee people's safety,'' he said.
"People blatantly drive past the signs and endanger their own safety and blatantly endanger other people's safety.
"It is conduct like this that puts pressure on Port Otago to simply close the wharf access. If we are to retain access to the wharves - which is our aim - we need more support from fishermen and more respect of operating activities,'' Mr Plunket said.
Putting gates up and closing off public access was a "last resort'' but fishers "had to show more respect'' and "exercise judgement'', especially during the salmon season when large numbers of fishers frequented the wharves, he said.
Not parking cars on wharves or fishing too close to machinery when work was being undertaken was a good start, as was not bringing children during those times.
Salmon fisherman Peter Tuisano (70), of Brockville, said it would be "pretty sad'' to be barred from fishing on the wharves but he understood Port Otago's position.
"I see what he [Mr Plunket] means. There are some people there - they just don't care and it affects all these people that love fishing. I would like to express to the people [the necessity of heeding the signs] ... Otherwise we will lose our opportunity.''
Regular fishermen on the wharves were there mostly to feed their families but also to relax and "take their minds off things'', Mr Tuisano said. He sent anything he caught "up north''.
"It's a very important part of our lives [and] it would be a big blow to the Dunedin community [to be banned from the wharves].''
New Zealand Salmon Anglers Association Otago branch secretary Pete Coory said members were concerned over Port Otago's blocking of access to the wharves and sheds near Fryatt St.
Fishers understood the areas needed to be blocked when a ship was docked, but once they had sailed the areas should reopen to fishers, he said.
"The fisherman are telling us they would like more access when there are no ships working.''
The association was not looking for a fight with Port Otago as it allowed anglers on its wharves for the Otago Harbour Salmon Fishing Competition on February 27 and 28, he said.
In Dunedin, Leith Wharf and the X/Y sheds were operating areas of Port Otago.
The X/Y sheds were restricted at all times to fishers and the T/U sheds were partially restricted and closed when a ship was docked.
Leith Wharf was restricted at all times but would be open for the fishing competition next month, if there was no ship activity that weekend.
At Port Chalmers, fishers could access deep water at the Boiler Point and Back Beach areas.
