The Department of Conservation (DoC) is considering restricting the number of people who can enter popular national parks at peak times.
In Tongariro National Park the number of hikers on the Tongariro Alpine Crossing reached 122,200 last summer.
High numbers are again expected over this holiday period, even without international tourists.
Conservation Minister Kiri Allan said DoC is exploring ways to make sure the numbers visiting national parks don't overwhelm facilities.
''This is an ongoing issue for us."
''We want to make sure we can preserve the values of these incredible places.''
She said DoC is always working to strike the balance between the number of people using the parks, with preserving the integrity of the environment.
Allan said DoC is in discussions with iwi about a possible trial to cap numbers entering Tongariro National Park.
She said she was confident the country's national parks are being looked after and maintained in an exceptional way by Te Papa Atawhai, DoC in conjunction with its various partners where that is appropriate.
''We are pretty confident there is sufficient resourcing there to do a good job.''