Perhaps just a pound or three heavier after a series of Christmas lunches and dinners, Mark and I headed up the Hume to join our friends Nick and Paul for a few days fishing in the mountains around the upper Murray. As usual on these trips, we had some ideas about where we might go and how we might fish, but no single lake or stream was the focus; we preferred to fish where the conditions and our mood suggested.

The bigger rivers caught our attention early on, with the odd diversion to smaller water. The Swampy Plain tailwater was mostly flowing at a good level (10 to 30 cumecs). Although the inevitable and unpredictable fluctuations in level upset the fishing at times, the solid head of trout (and their willingness to eat a dry!) made for addictive fishing when the river settled for long enough.

When it didn’t, the nearby Indi was one of several more than adequate alternatives. In the lower (Biggara) valley we fished for cod with some success, but the trout were a regular distraction. On one enticing glide lined with cod snags, a fat rainbow insisted on rising non-stop in the bubble-line – even after some six inch cod flies were dragged right past it. Eventually, that trout got the better of me. I added a length of 4X to my 30lb cod tippet and tied on a Red Para Spinner. Trying to gently present a tiny dry with an 8 weight rod and an aggressive RIO Outbound line (with intermediate tip!) was almost comical, but eventually I pulled it off and landed the trout.

Paul has caught cod up to 80cm in the same stretch, so we wondered what strategies the trout employ to avoid being eaten? Clearly those strategies are successful – we saw plenty more trout rising in what looked to be perilous proximity to cod snags. And keep in mind, this was during the very same session when we’d caught or missed some aggressive cod on flies not much smaller than trout. There’s another mystery to solve about rivers and fish; as if there weren’t enough already!

A big downpour on Friday night had us wondering what would be left to fish Saturday morning. Luckily, it turned out that high, dirty water was at its worst in the lower valleys, and a trip up the Alpine Way into the heart of the high country, revealed that the upper Indi and some smaller streams – while up and coloured somewhat – were more than fishable.

In fact, it seemed that the fresh had given the trout a kick and it turned out that Saturday was our best day of the trip. It was also a day when the Royal Wulff – an old generalist favourite which has been usurped somewhat in recent years by the Stimulator – regained some lost prestige. While very different flies to look at, I’ve often regarded these bushy, somewhat flashy dries as relatively interchangeable. Not so on Saturday. There were enough trout sighted before casting to establish that this day, Lee Wulff’s masterpiece was king – even along streams where grasshoppers swarmed and the more hopper-like profile of the yellow Stimulator especially, seemed a better general match.

As we drove home yesterday and the mountains receded to a blue smudge in the rear view mirror, it occurred to me that despite so much good (and at times simply phenomenal) fishing, there were still lots of questions left unanswered. For example, the small stream where seemingly identical (and apparently perfect) stretches varied from full of action, to barren. One minute, it was almost a fish a cast, and then the next hundred metres, nothing. Not a rise, not a miss, not a spooked fish. Then suddenly, the trout would be there again. Mark and Nick, fishing a kilometre downstream, reported exactly the same feast-and-famine fishing.

And evening rises. They were great (except of course during Friday’s deluge) but why is it that sometimes, one stretch – even one part of one stretch of a river – can produce a frantic hatch/ fall and rise, while identical water a bend away, is dead? Then there’s the unusual number of larger trout on the small to medium-sized north-east streams this season. What has driven this? Unlike after drought or bushfires, overall trout numbers are solid this season, so lack of competition doesn’t appear to be the explanation. Has something else worked in favour of trout growth rate? Lack of extreme heat or cold this last year or so? Prevalence of ‘ideal’ drift feeding flows versus flows that are too high or too low? Consistent water clarity perhaps (again favouring ‘easier’ drift feeding?)

Without hard information, Mark and I could only speculate, but the topics made for good conversation as the Hume Highway’s endless blacktop stretched ahead, and we clocked off for another fishing year.