The Stone Zone Theory

Nick Reygaert fishes New Zealand’s Lake Pukaki

We had been fishing the stone bank for around an hour. In less than a kilometre of walking, we had seen at least 30 trout cruising the shoreline. Most of the ones we’d seen had pounced on our streamers, and a good portion of those had come to hand. Excitement levels were high. It seemed that at any one time, either Ronan or Jeff was spotting, presenting, hooking or fighting a brown trout. As they leap frogged each other along the rocky shore to intercept the next fish, I scurried along to try to capture the action with photos and video. It was hectic and fun, two words I don’t usually associate with winter fishing. August is generally not held in high regard by fly fishers in New Zealand’s South Island, but the longer I live here the more I’ve come to realise that the fishing is great here every month of the year, especially if you are prepared to alter your mindset and techniques to make the most of the situation. I film and direct a TV series called Pure Fly NZ, which is now in its fourth season and has been well received on TV channels across the globe. One of the great things about making the series is that it has forced me to look for unusual trout fishing scenarios, because there are only so many episodes you can shoot in the South Island backcountry before it becomes monotonous. Variety is the spice of (fly)life. Keeping an open mind is greatly enhanced by the company you keep, and my winter fishing has been massively inspired by the antics of Ronan Creane and his great mate Jeff Forsee. Winter fishing requires a fair dose of enthusiasm — the mornings will be cold and the days short — and these two characters bring a fishy buzz that quickly eclipses any hardships. THE RUMOURS Ronan fishes as much during the winter months as he does in the summer, and it was his stories of catching big rainbows from his boat in Lake Hawea during August that got me thinking. I’d heard a rumour about the mysterious Lake Pukaki — the giant glacial lake that sits at the base of NZ’s largest mountain, Mount Cook. The old-timer had been a station-hand on one of the large properties bordering the lake. He told me that in August big rainbow trout gather at the river mouths to start their spawning migration. He had assured me that double figure fish had been taken. It was a story I filed away in my memory bank. I floated the idea of an exploratory filming mission to Jeff and Ronan whilst having a few beers après-fish in April. Their immediate response was, ‘Lock it in Reygaert.’ A date was set for mid-August and we agreed that bringing my raft would open the whole lake up to us and add an extra element of interest to the episode. Winter trundled by and we had very little snow or rain. It was the driest winter I can remember in the last decade, but I gave the dry weather very little thought as we would be lake fishing. The first morning was calm and foggy, as it often is in winter in the South Island. I immediately remarked on how low the lake was when I first viewed it — about 3 metres lower than I’d ever seen it. A number of small streams enter the lake and most are readily accessible from public roads around the shoreline. I have regularly fished these stream mouths in the past and they are usually productive, so I was surprised when we failed to hook any fish in the first hour. Not to be deterred we went to the next stream a few kilometres up the road. This is larger and can always be relied upon. We saw a number of brown trout cruising the shore but they were very lethargic and the boys failed to get a positive response to their streamers. Lake fishing in winter can often be dictated by water temperature and it felt like the sun needed to pop out to work its magic and just raise the temperature a degree or two. I had one more place I wanted to try and promised the guys that this would be the best of it. Braided river channels enter at the head of the lake and at normal lake levels they form bays with hard shingle bottoms. These can be waded easily and have fished quite well for me in the past, but as we pulled up in the cars and looked across the delta my heart sank. With the lake so low, the delta had receded almost a kilometre from where I’d fished it before. This had exposed the muddy, silty bottom of the lake. It didn’t look very inviting. The guys looked at me with daggers in their eyes. I shrugged and told them that we should at least give it a go. Jeff was the first to reach the delta and as he started to walk towards the lake I watched him slowly sink deeper into the silt until he was knee deep and nowhere close to the water. It was unfishable. I glanced up the shore a few hundred metres to where I could see the rocky perimeter meeting the water’s edge. I looked at the guys. We’d come this far so might as well check it out. As soon as we got to that rocky shore Ronan spotted a trout cruising. It refused his fly but then a moment later another fish appeared and he briefly hooked it. This was more like it. THE ROCKY SHORE Ronan pushed along further and soon told us that he was onto another fish. Meanwhile Jeff was launching long casts into the deeper water and also got a hit. The action was heating up but we still hadn’t landed a trout. Until then it had been very still, without a breath of wind, quite typical for a winter day. But as the last of the fog burnt off and the sun appeared, the slightest of breezes fanned in and small waves began to break along the shore. Everything from that moment on is a blur in my mind. It seemed that the dirty water resulting from the shore break was drawing the cruising trout in closer, and they were hunting with intent. Perhaps too, the sun had warmed the water to a point that had stirred the fish into action. Whatever the cause, the result was a cruising brown trout every couple of metres. Each one that was presented with a streamer raced towards it with an open mouth. Ronan and Jeff quickly landed half a dozen trout each, all browns of good size. At one stage I looked up the shoreline to see at least five trout hunting along in a line, like a phalanx of Roman soldiers moving in close formation at exactly the same speed. It was incredible to see. Jeff and Ronan cast simultaneously towards this posse of cruising brownies, and as the flies landed, the fish broke rank and leapt onto them. Pandemonium ensued with two hooked fish leaping around and the others slicing through the muddy water trying to get a piece of the action. Is there anything better in fishing than a double hook-up with your best mate? To pull that off on a winter’s day when many would still be rugged up in front of the fire makes it even sweeter. THE THEORY All three of us are guides and have done a lot of stillwater fishing in New Zealand. We all agreed it was the most impressive action we had ever experienced on a lake. The number of fish we encountered was impressive, as was the average size of the trout. Once the dust settled we sat on the rocks for a moment to catch our breath. Like all fishermen, we started theorising as to why it happened. What was the main driver of such an event? Jeff was quick to remind us of a moment when he was releasing a trout, and as he stood on one of the rocks on the lake edge a number of bullies had shot out from under it. He yelled out at the time how unusual that was, but there was so much going on that I paid it no heed. Obviously Jeff had been ruminating on that event and he launched into a theory. He pointed out that just a few feet of rocks reached below the surface before they hit the silty bottom — this was the same along the entire stretch of shoreline we’d fished. The bullies were hiding under the rocks because they provided good shelter as opposed to a silty bottom that offers no cover. He then surmised that at normal lake levels the bullies would have all the rest of the rocky shoreline to spread out and inhabit, but with the lake so low this had been compressed to just a few rocks along the edge. The trout were tuned into the situation — more prey items condensed into a smaller area leading to more opportunities. Then add some wave action, a bit of dirty water, and presto, you’ve got yourself a brown trout fiesta. I usually like to come up with my own theories (part of the fun) but this one was too good to dismiss. Jeff was onto something. A plan was made for the next day: we would try the other side of the lake to see if we encountered a similar situation, and we would keep a couple of fish to examine the stomach contents. The Stone Zone theory was born and we wet the baby’s head that night to welcome it to the piscatorial world. THE PROOF We decided that the raft would give us the most flexibility for exploring next day, especially as it was forecast to blow down the lake. We could put in at the delta and be blown along the shore, allowing us to cover a huge amount of water without the walking. The raft was launched and we rowed into the muddy delta to begin fishing. It looked pretty good and we expected to encounter at least a few fish. But no action after 30 minutes and plenty of casts. As we drifted, in the distance we could see where the rocky shore began, and as it loomed closer we wondered out loud if the Stone Zone theory would be proved correct. Jeff was on the seat at the front of the raft and was first to get his fly into the Stone Zone as we drifted. A couple of big strips and he was tight into our first fish, a nice brown that was holding just a few feet from the shore. He landed it quickly, a few photos and it was on its way. We had drifted into prime rocky shore and it was Ronan’s turn to pull a nice brown that was holding in a small pocket behind a big rock. And so it continued for the rest of the day. The boys pulled trout, both browns and rainbows, from any shore that had good rocky structure. As soon as the shore turned sandy or silty, the action would stop. The wind increased during the day but the fishing got better until eventually it became too hard to handle the raft. Tired and elated, we pulled ashore. We had drifted about 4 kilometres of shoreline for the day and both fellas hit double digits for trout landed. Ronan kept a nice fat rainbow and brown for the table. I was very eager to see what they had been eating, and sure enough, the brown had a bully in its stomach and little else. The Stone Zone theory was further enhanced. But the biggest surprise came when Ronan opened the rainbow’s stomach and two bullies popped out, one of which was still alive! Ronan very gently released it back into the lake and as it swam off strongly he announced in his Irish accent: ‘That there is the luckiest bully in the whole of New Zealand!’ I felt pretty lucky too, and made a mental note to fish more in winter.

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