A spokeswoman said the body provided a variation to the licences of tour operators that were offering rock climbing and abseiling at Summerday Valley, near Laharum, authorising them to continue doing so for three months.

"We appreciate there were rock climbers, tour groups and other park visitors who were not previously aware the Grampians National Park's Special Protection Areas," she said.

"We also understand our decision to begin strictly enforcing the restrictions that have applied since 2003 in those areas has meant that climbers and tour operators have had to modify their activities.

"Climbing is allowed in Mount Arapiles-Tooan State Park, as it is in the 100,000-hectares of Grampians National Park that is outside of Special Protection Areas."

Climbing is prohibited in all Special Protection Areas, of which the valley is one. SPAs seek to protect cultural heritage and environmental values.

It comes after a Natimuk rock climber who runs tours at Summerday Valley called for clarity on how the new system for tour operators would work.

Previously: A NATIMUK rock climber has called for clarity on how a new system to protect safety, conservation and Indigenous sites in the Grampians National Park will work.

Arapiles Climbing Guides owner Hugh Widdowson says businesses such as his now needed to use a booking system when they ran abseiling and climbing activities in Summerday Valley - at the park's northern tip.

On Friday night, Parks Victoria announced licensed tour operators would be allowed to undertake tours at Summerday Valley for three months.

Parks Victoria has also installed signage and undertaking enforcement activities at eight locations in the Grampians since March. These are Gondwanaland, The Gallery, Millenium, Billimina Area, Billywing Buttress, Little Hands Cave, Manja Area and the Cave of Man Hands.

The state government has said the bans are justified because visitor numbers and modern climbing techniques have caused losses to vegetation, negative impacts on rare and endangered species and damage to Aboriginal rock art.

Mr Widdowson said he was hopeful Parks Victoria would extend licence variations after three months.

"There have been ongoing problems with overuse and crowding, so this booking system is an opportunity for Parks Victoria to address some of those problems," he said.

"The way the school timetable goes, school groups have very small windows for when they're able to do field trips like this, so the environment has a lot of pressure put on it over those periods."

Mr Widdowson said there was room for Parks Victoria and the state government to improve communication with climbers and operators.

"As of Saturday morning, how the booking system would work or be managed wasn't clear," he said.

"It is possible for licensed tour operators to make bookings, but the process hasn't been clarified yet. Also, recreational climbers are not included in the booking system at the moment, so I think the Summerday Valley is being listed as one of these Special Protection Areas and climbing is excluded from those areas except for licensed tour operators.

"I'm hoping there will be an understanding between climbers in general, Parks Victoria and traditional owners that climbing will be seen in a positive light."

Member for Lowan Emma Kealy also called for more communication and consultation from the government.

She said there had been no publicity regarding the Grampians Landscape Management Plan - the drafting of which began in May and will seek to protect the region's environmental and cultural values for the next 15 years.

"They are not telling people this consultation phase is going ahead, even though they are closing parts of the Grampians," she said.

"The odd part is there is no rock art through that area. The concerns relate to a quarry site on the bed of the valley so they don't want people walking on it. For my mind this is just the start of it - you ban rock climbing, but the concerns might be about objects on the ground, in which case do you ban bushwalking?"

The Mail-Times has contacted environment minister Lily D'Ambrosio for comment.

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