Still waters can be productive when rivers are too warm

Otago Daily Times angling columnist Mike Weddell on the Waipahi River. Photo: Supplied
Otago Daily Times angling columnist Mike Weddell on the Waipahi River. Photo: supplied
PHOTO: ODT FILES
The rain this week has raised rivers a little mainly in the west, while those in the east remain very low. The Taieri’s temperature at Waipiata rose to 24°C on Wednesday, which is a dangerous level for fish.

Luckily, the weather cooled off on Thursday and a little rain also helped. When rivers are very warm, still waters can provide good fishing in deeper water as fish retreat there as the water is cooler. The surface water cools off at night, so the best time to see rising fish will be early in the morning and the best fly to try for them is a midge pupa. The warm days have produced some good fishing to fish feeding on cicadas, sometimes, but on other days trout have not risen to them.

The Maniototo dams are usually a good option when rivers are warm and low but my favourites are not fishing so well this season. Blakely’s, Rutherford’s and Mathias’ dams have not been stocked with rainbows this year, due to hatchery water overheating last year and killing off the juvenile rainbows that would have been introduced last year and caught this year as takable fish.

Mathias’ has brown trout in it, but not many have been caught due to high levels of weed and algae. McAtamney’s head pond and the Styx weir pond are good alternatives as they receive cooler water from the Loganburn.

I have been out and about recently fishing several different waters. The first session was on the lower Taieri, where I expected to see trout rising to willow grub. There were a few rises, but I was pleased to feel the water had cooled down to a comfortable level for trout. I only spotted one trout in the water, so the rest of the time I covered likely areas for trout to be lying. Light areas on the gravel where fish had rubbed algae from the stones and snags such as weed beds and tree stumps and fallen branches were targeted and produced a few fish on an unweighted nymph.

Another outing was to Loganburn Dam on a hot windy day with Wayne Gillet and Bruce Lambie and although there were a few cicadas in the afternoon, we did not see a single rise.

We met a woman fishing from a dinghy who had a caught a couple of nice trout in the morning and had caught several the day before. The latter were full of cicadas, a classic case of you should have been here yesterday.

I watched how she fished and she obviously knew what she was doing. She trolled very slowly with an electric motor running parallel to the shore and had caught her fish on a goldy Tasmanian Devil. She also did not bang about in the boat. Some lessons to be learned there.

Even though fish were not rising they were feeding and were catchable on midge pupae and damsel fly nymphs and were caught cruising over silty areas and where the waves were breaking on the shore.