More needs to be done to stop people defecating on the top of Mt Taranaki, says a retired conservation manager.
Debate over cultural protocol continued following recent discussion about scattering ashes on the sacred mountain.
Retired Department of Conservation manager, Phil Mohi, said DoC needed to monitor the site to make sure people respected the cultural protocol at the mountain's summit, which multiple Taranaki iwi view as a living ancestor.
"After five or six hours of strenuous climbing, when you get to the top and sit down it's a natural bodily function to want to go to the toilet," he told Fairfax.
Mr Mohi said the number of people visiting the summit was increasing every year and the toilet problem would likely get worse.
"At any other site which sees this much traffic a local authority would say you need to either direct sewage or build more facilities," he said.
Building a toilet at the top of the mountain would also contradict cultural values and was not an option, Mohi said.
Currently the closest toilet is still a three to four-hour hike from the summit.
One solution could be for visitors to defecate into plastic bags and take it back down the mountain with them, which is the system used in other parks around the world.