Although Northland doesn't present great fly fishing option, in comparison to the rest of NZ, there are still nice areas to explore, and, trophy sized fish of up to 4.5kg (10lb), are possible at Kai Iwi Lakes.
The rivers holding a possibility of a trophy trout include, the Waikato, Whanganui, and Whakapapa Rivers.
Lake Taupo and most of the rivers and streams feeding into the lake have the potential of trophy trout. The Tongariro, being the largest, and, most productive fishery, for trophy brown trout in particular. Lake Otamangakau is also noted as a trophy fishery.
The Manganuioteao holds the best chance of a trophy trout, although, fish above 6-7lb are in reality very rare. On the Taranaki Ring plain, fish of 10lb are present below the Patea Dam. On the ringplain itself, a fish of 6lb is considered a trophy, and these occasional are caught in the Stony, Waiwhakaiho, Manganui, and, Kaupokonui Streams.
The Motu, Ruakituri, and Waiau offer the odd trophy trout, but they are more often caught in the lakes around Rotorua in this region. Lake Rotoiti, Lake Okataina, Lake Rotorua, and others hold good numbers of trophy fish. The Ngongataha stream is noted for trophy fish.
The hawkes bay has a number of fine headwater fisheries that occasionally produce trophy fish. These are the Mohaka, Ngaruroro, and Tuki Tuki rivers.
The most noted trophy trout fishery in the region is the Upper Rangitikei, where fish of 10lb are possible, although difficult to catch. Rivers flowing out of the Tararua ranges, occasionally have a trophy trout in them, although the rivers themselves are not known as trophy fisheries. The Hautapu near Taihape, also has the occasional trophy.
The South Island rivers are large and varied, and because of mast years, and mouse populations explosions, many rivers are capable of producing trophy trout. A lot of walking between fish may be required, but the effort can be worth while on rivers such as: The Wairau, Goulter, Spring Creek, Travers, Sabine, D'Urville, Wangapeka, Waingaro, Aorere, Waimea.
Again, with the abundance of beech trees, many rivers are capable of trophy trout. Rivers to explore include: The Matakitaki, Glenroy, Maruia, Larry's Creek, Waitahu, Stony, Deepdale, Karamea, Ugly, Roaring Lion, Mokihinui, Clarke, Haupiri, Rough, Big Slatey, Waitangitaona, La Fontaine, Moeraki, Okuru, Deepdale, Cascade, Thomas and Jackson.
North Canterbury has a number of big fish rivers these include: The Hurunui, Waiau, Hope, Boyle, Doubtful, Clarence, Waimakariri, and, Poulter.
Central South Island
The occasional trophy can show up in the many lakes and rivers in the area. Of note, would be the upper Ahuriri, and also the canals around Tekapo.
The scenery in this area is stunning. Trophy fish often swim up from the lakes into the various rivers. Rivers such as The Makarora, Young, Wilkin, Hunter, Greenstone, Caples, Nevis, Routeburn, Lochy, Matukituki, and, Kawarau rivers, can produce large fish at the right time of year.
A great region to explore and find trophy trout. Rivers to fish include: The Oreti, Pomahaka, Mataura, Mararoa, Wairaki, Borland Burn, Clinton, Worsley, Glaisnock, and Eglinton.