Could climate change really be responsible for changing the colour of Taupo trout? This season TRM smoker has seen a run of much darker trout – both Rainbows and Brown Trout. Some anglers often dismiss them as inferior (?) due only to their darker colour, claiming they are resident trout? That suggests they migrated up from Lake Taupo to spawn and stayed on to turn dark in the river environment, instead of returning to the lake. There are still some errant trout who have not read the book yet and behave irrationally. SWMBO’s standard explanation, which appears to satisfy all but the most curious, is that the darker colour is due to “climate change” (?) and the fish is just as good as a gleaming silver fresh run bullet. Most fishos seem to accept that, but there may be another reason…

Back in the 19th century Rainbow and Brown trout were first introduced to the Lake Taupo region from four different sources. I know some fishy books have claimed that they all came from the one Russian River near San Francisco, but there is more to it than that. They came as steelhead ova from various rivers on America’s West Coast.

Back then NZ (forget the South Island) had four acclimatisation societies – from Wellington, Auckland, Napier and New Plymouth. Each claimed the Taupo lakes and rivers as their jewel in the crown and were keen to stock them. Each sourced their ova, aka eggs, from different sources at different times. Sometimes it took several attempts before they were eventually successful.

“The Auckland Society’s efforts are well recorded when they released them in the Auckland Domain – see images above – and then transported to the Okoriore Springs before releasing them in the Waikato River above Huka Falls. The plaque in the Domain reads: “This centennial plaque was presented to the Auckland Acclimatisation Society to convey the gratitude of past, present and future generations of trout anglers in New Zealand for the Society’s successful importation of Californian Rainbow Trout ova in 1883, its hatching of the eggs in the Auckland Domain ponds and its subsequent distribution of the fish and their progeny to many New Zealand waters. Turangi 18th April 1983”

The Wellington Society apparently released their ova in the upper Waikato River (aka upper Tongariro River) from the Desert Road. The Napier Society released their ova in the upper Waitahanui River. The New Plymouth Society released their eggs somewhere over on the Western Bays – possibly Kuratau Stream? So each release was originally sourced from a different river in California and they are now all regarded as NZ Rainbow Trout. The Brown Trout came from England via Tasmania in West Island.

But one of the releases must have included a strain of darker coloured trout. These have been reported caught in the lake before making their spawning run up the river, so it is nothing to do with their time in the river. So this TRM message for anglers is not to dismiss any trout just because of the darker colour. Examine their physical condition first. When they are filleted the flesh colour will be just as good – deep orange and full of flavour. So now you know… More examples of darker coloured strain of Taupo trout (and anglers?) are in the TRM inmates images below.