"It's the first time in five years the opening has fallen on a Saturday, and being in the middle of school holidays, it provides lots of opportunities for families to get out on the water," said Fish and Game officer Mark Sherburn.
"The competition adds an element of intrigue to the start of the season with lots and lots of people talking about it on the water last year."
Other envelopes in the competition contain a $200 tackle or voucher prize, so every eligible angler who returns with a green tag fish will win something.
The competition is Fish and Game's way of giving back to the community.
"By spicing up the first nine days of the new season and adding to the thrill level, we'll hopefully attract more folk who are potential customers of local businesses, be they accommodation providers or fishing stores.
"So our advice to trout anglers is to come to Rotorua for the entire first week of the fishing season and make the most of this opportunity. You'll find there is a licence to suit no matter what your holiday or fishing plans."
Fish for Gold is free to enter. All you must have is a 2016-17 Fish & Game sports fishing licence. The promotion is limited to the first 1200 entries - and you must register online before opening day.
Details including entry form and terms and conditions can be found via Eastern Fish & Game's pages: http://eastern.fishandgame.org.nz/newsitem/tagged-trout-promotion.
What: Fish For Gold
Where: Lakes Tarawera, Rotoiti and Okataina.
When: Tomorrow to October 9.