My Understanding is that Tuwharetoa have an agreement with the Crown to grant foot access along the lake shore and along tributaries where fishing is allowed in return for half the license and fines money that DOC collects. Since over time the license sales have dropped to almost half, the remuneration has been changed to a set sum regardless of how many licenses are sold. I am sure DOC would want to get out of this but if they did Tuwharetoa would be free to privatised the fishery and set their own rules.
It is also very doubtful that F&G would want it considering the additional cost they would have to manage such a big fishery on the income of a universal license. Don't forget that a lot of Taupo license holders also buy a F&G license to fish elsewhere so there would be little change in income for F&G.
As for bag limit change this is another story.
1. The lake is nutrient poor that is why it is so clear
2. There are acres of spawning gravel capable of producing an excess of fingerlings.
3. Smelt population varies from year to year depending on nutrient supply.
4. License sales have half since the mid eighties
5. C&R is widely practiced
6. Limit bags have dropped from 10 to 3 over the years.
What that means is if there is a year of high trout recruitment in the spawning streams and a down turn in the smelt population there an imbalance and new fish entering the lake are starving. This has happened dramatically from 2005 onwards and has only normalised in the last three years with a rise in productivity and an increase in harvest.
Taupo must be harvested heavily to keep smelt and trout in a health balance.
Cheers
Rainbow