Perfect conditions to encourage a fresh spawning run for the next week…. But how long will the runs last?

How long is a piece of string?  TRM get asked the same sort of questions every fishing season.  This time a West Island novice angler wants to know when is the best time to stay – when the Tongariro spawning runs peak?  Everyone has their own theories on this.  The trout have not been interviewed – yet.  The following is part of our reply to him.

We try to answer all these questions and try to refer them to DoC (Department of Conservation are the Taupo Fishery Managers) and keep them interestingly different enough each season (?) but the truth is we rely more and more on other inmates input as She does not allow me out on the river every day.  Alternatively, if in doubt, we turn to TRM’s library.

The following is copied from John Kent’s North Island Trout Fishing Guide – first published 1989 – re Fishing Taupo rivers:

“From the end of March to the end of November, the vast majority of Taupo trout intent on spawning enter the rivers and streams flowing into the lake.

By July the rivers are full of fish. 

By September many are spent and drift back down stream to the lake to recover.  A run of fish usually enters a river as a fresh recedes and makes its way upstream over the enxt few days.  The run may be spread over several kilometres of river and the restof the river may be very quiet.  Thirty days is the average time for a run of fish to reach the Whitikau tributary of the Tongariro River, although some make it in 18 days while others may take 80 days.”

Another source is Wallace Bain & Barry Greig’s book – Fishing Guide to the Tongariro River published 1983.  They comment:

“RUNS UP THE RIVER – These usually occur between May & September but some fish start as early as March while other may be as late as November.  Recently, some fish have been observed spawning during summer but what brings this about is unknown.  Traditionally the spawning run used to be between May and July but that period is now considerably extended.  It is thought weather conditins may play a role and a lower river level throughout winter may induce the fish to spawn in ‘dribs and drabs’ rather than in concentrated runs.

Trout are capable of travelling up a river for over 40 km or more overnight.  They generally run during the dark unless there is fresh water in the river.  The distances travelled vary according to how far fish have to go to particular spawning grounds so as to ensure they arive there ripe.  The majority of the trout hang off the river mouth until they are ready to spawn and then they come straight up the river.

But a few may enter the river up to two months before they are ripe.

Trout spawn throughout the Tongariro River and individuals generally return to the same spawning grounds each year.  It is a misapprehension that that main spawning grounds are in the upper reaches of the river and up the Tongariro’s many tributaries.  In recent years (this was written 35 years ago) more spawning appears to be taking place in the main river, especially above the SH1 bridge….

OK.  Since then the data changed as the Whitikau trap has closed and the only recorded data is from the Waipa trap much further up river – arguably taking another 20-30 days as the trout must be tiring by then. This is where DoC publish their more recent analysis from – which in recent years indicate the biggest runs through the trap are in October/November. (?)

But that is misleading for anglers as the bulk of those trout are most likely probably passing through the town pools now…

About 15 years ago (?) DoC attached aerials to a number of trout and their movements confirmed there was no distinct pattern.  Some went directly up river, some went up and down four times smelling out every tributary, one even swam back into the lake and was last recorded over in Western Bays.

The only identifiable characteristic was that there was no discernible regular pattern.  Their average time exploring the river before they reached the spawning grounds was about two months, then add another month to reach the Waipa trap..

The biggest run I personally have seen was a couple of years ago in early January.  The run of trout was stretched right across the lower Major Jones Pool.  That made no sense at all – they had not read Greig’s book either..

So they could pass through the town pools at any time from now until November…

But the best time to fish the Tongariro is whenever you can get here.

Image below of TNTC volunteers at the Waipa Trap: