Fiordland tourism operators say the rules governing the national park are outdated and leave no room for common sense.
Each national park is required to have its management plan reviewed every 10 years or earlier with public consultation.
Fiordland's rules were due to be reviewed in 2017, but the review was delayed.
Ultimate Hikes general manager Noll Saxon said working under the current rules could be frustrating.
He tried to find a different place for his guests to disembark to ease the pressure on the often-crowded Milford Sound terminal.
But under the rules, that can't be done.
"It seems like common sense, certainly I'm sure that would get a lot of support. But we would like to have that conversation, currently we can't have that conversation because there's no opportunity to review the condition that doesn't allow us to disembark anywhere else apart from the current terminal location. There's a simple example of what we'd like to be able to do," Saxon said.
While the rules could be challenged, that cost time and money that many small operators couldn't afford.
Operators just wanted a say on their role in the future of the national park, Saxon said.
"There will be a lot of concessionaires out there saying 'Well, this is how I used to operate. Now in order to survive, I need to operate differently'. I'd like to think that DOC (Department of Conservation) could address those in a reasonably quick manner."
'Out of date'
A Fiordland tourist operator who spoke on the condition of anonymity said businesses were being stifled under the plan.
"It's out of date by a long time and it's not helping any businesses operate or grow in Te Anau. Te Anau is the envy of most parts of the world with the beauty and location that it has, but we're just not in a position to grow," he said.
His company had a consent limiting the visitor numbers he could cater for.
He wanted to attract domestic visitors to spend their money in Fiordland post-Covid-19, but said the visitor limits were a liability.
Destination Fiordland manager Madeleine Peacock said the current rules were putting up road blocks for businesses before Covid-19 struck.
"There's certain things where what concessionaires have been told they can do does not line up with the national park management plan," Peacock said.
"Operators have been doing legitimate activities under their concessions and have subsequently been told by the department they can no longer do that."
Concession issues couldn't be sorted until the rules were reviewed, she said.
"Is there going to be support for legislative change to enable tourism businesses to actually kickstart and to do what they need to do to be able to take advantage, firstly, of domestic tourism, but second, international tourism when it comes back," Peacock said.
DOC southern South Island operations director Aaron Fleming said reviewing the rules for Fiordland was a priority.
The rules guided not only how businesses operated in the national park, but also how parks were managed into the future, Fleming said.
"In many senses, it's the contract that we have with New Zealand in terms of how we are going to manage that place. So in order to do anything quickly, it's difficult because you know we have to work through a process and work with New Zealand - in terms of the public and their views - to help determine what might be the future aspirations for that particular park."
He acknowledged a new plan would be years away as it took time to consult and work through the process.
But Fleming said it was vital to get the rules right.
"You know we agree, context changes all the time. We're seeing that with Covid at the moment and the more agile or responsive a plan can be to these changing environments, we think that's best as well whilst protecting those values."
Fleming said DOC welcomed operators to contact them to see if they could find solutions.
The department will be in touch with concession holders next month about potential support.