Trout, deer, pigs and other exotic species would have to be culled from the Ureweras under a law change before Parliament, fishers and hunters are warning Government.
Fishing and gaming associations say that in the Te Urewera-Tuhoe Bill, the emphasis on exterminating introduced animals from the Te Urewera region appeared to have increased in importance.
As part of the Crown's unique Treaty of Waitangi settlement with Tuhoe, Te Urewera would be legally owned by nobody but jointly controlled by the iwi and the Crown.
In New Zealand's national parks, the Conservation Authority had discretion over which plants and animals were "exterminated" to protect native species and bush.
Fish and Game Council chief executive Bryce Johnson said it appeared that a new board which would manage the Ureweras did not have the same discretion.
He said that as the bill stands, officials would have to make every effort to exterminate all introduced species.
Introduced species included pests such as stoats and possums but also recreational fishing stocks such as trout and popular game animals such as deer and pigs.
Mr Johnson said it was unlikely Tuhoe would want to get rid of all deer and pigs, which some of the iwi hunted and depended on as a food source.
In its submission, Fish and Game said: "The principle of acting as far as possible to exterminate introduced plants and animals will in fact reduce the provision for Te Urewera as a place for public use and enjoyment... This principle then as drafted appears to be in conflict with one of the key purposes of the bill."
Tuhoe said yesterday that it was waiting for the Maori Affairs select committee to report back on the bill before it considered some of the key issues.
The iwi did not plan to exclude the public from the Ureweras.
Maori Affairs Committee deputy chair Te Ururoa Flavell said he did not believe that Tuhoe wanted to exterminate game animals and an amendment was likely.
Mr Johnson was also seeking a change to the bill which would prevent recreational fishers from needing two permits to fish in Urewera waterways, such as Lake Waikaremoana.
The law change would require hunters and fishers to get an activity permit from the new Te Urewera Board.
Mr Johnson said sport fishers already needed a license, and it was "a nonsense" to introduce another layer of bureacracy and potentially new costs.
He said that officials had assured him this was an oversight and the bill would be amended so that fishers would not require a second permit.