As autumn gets into full swing and the first of the April showers send a good flush of fresh water down the streams that drain into any of the lakes containing brown and rainbow trout in New Zealand the trout spawning migrations begins. While spawning of brown trout won’t take place until late autumn/early winter and that of the rainbow later still, these first few flushes of fresh water trigger an innate urge within lake trout to move into feeder streams and begin a journey to their upstream spawning sites.
After the excitement of summer dry fly-fishing to both species, most anglers look with despair towards the inevitable approach of winter. Yet there is still some fun to be had. Autumn runs of lake fish greatly increase the population of trout in rivers and streams. Waters that were relatively barren during the summer months can provide some exceptional fishing with potentially large numbers of well conditioned trout to be caught.
Browns and rainbows continue to feed on their spawning migrations unlike some other salmonid species and therefore can be caught using a variety of techniques depending on the species being targeted and the conditions of the day. Brown trout are the first to move into the rivers and these fish will continue to feed heavily while making their way to the spawning redds. In lakes where they coexist with rainbow trout, their migration will be closely followed by rainbows who are intent on getting a free meal of brown trout ova. It is these different feeding strategies of the two species that dictate the approaches taken when targeting fresh run fish.
The closer the fish get to their spawning beds however the less likely they are to take a fly and the more interested they become in each other as their sexual urges take over. In any case, these fish are best left alone to get on with the business of producing baby trout. The extra stress of being caught will only result in the dropping of ova or milt and potentially a failed spawning. However, fresh run fish are definitely a prospect worth dedicating some time too.
Browns Stacked Up
I first stumbled across a large run of lake browns in April 2004 while out on a Sunday drive with my partner. We were on an extended stay in the Mackenzie district on the South Island and I had been fishing the local freestone rivers almost daily. On this particular day however, while driving along a smallish stream that fills Lake Opuha, I managed to talk my partner into a short walk along the river bank. As we approached the water I put on my polaroids for a quick scan of the water. I had fished this particular stream in November at the start of the season and could not find a fish, so expectation of spotting a trout was not high. To my amazement in the first pool we came to four big browns were stacked up one behind the other. I couldn’t believe it. A short stroll to the next pool and sure enough another couple of trout could be seen darting from side to side taking nymphs. This was a revelation as the freestone streams I had been fishing required a great deal of walking between fish.
Over the next three days I experienced some exceptional fly fishing. The browns were eager to take both a dry and nymph, appeared less cautious than their river dwelling cousins and due to their dark spawning colours were more easily sighted. The browns were not only stacked up in the pools, but the riffles had an even greater number of fish. Even the disturbance of playing a fish didn’t put other fish holding in the same pool down. This is probably due to the fact that during this time, trout, in particular the jacks, spend a lot of time chasing each other around, competing and vying for the attention of the hens.
I prefer to target these fish with a dry, generally a dun pattern such as a parachute adams, or a generalist such as a royal wulff or stimulator, with a nymph dropper from the bend of the hook. A nice big dark nymph is my favourite and a gold bead head really works wonders on these fish. Another effective technique is to swing a big black Woolly Bugger across a riffle containing fish. This really gets the testosterone boiling in the jacks and savage takes can be expected.
The North islands Rotorua fishery is based on the migration of browns up its tributary streams and provides excellent autumn fishing. I have recently had a similar experience to that described above while fishing the Whirinaki river – a river that receives a spawning run of browns from Lake Aniwhenua. However, all wild self sustaining brown trout lake fisheries will have a migration of brown trout up its feeder streams so it pays to investigate these streams prior to the end of the season, you could be in for a pleasant surprise.
Rainbows on the other hand require a different approach and one of the most successful ways of targeting fresh run rainbow trout is with the Glo-bug. While fish will still be taken on nymphs fished upstream and streamers fished across and down, you can forget about fishing the dry to these fish.
The technique of upstream nymphing with a bomb and Glo-bug has been well documented; however, it is worth reviewing it here to highlight the different approaches required when fishing to running rainbows as opposed to browns. The most common way of fishing the Glo-bug is to tie it on a short dropper (10-15cm) from the bend of a big tungsten bead head nymph and fish it under a highly buoyant indicator. The more cost effective approach and equally effective is to use the one fly, a Glo-Bug, and add split shot to the tippet 10-15cm above the fly. Nine times out of ten the rainbows will take the Glo-bug when fishing it paired with another pattern, so why not revert to one fly and save time with inevitable tangles that occur with this type of fishing. The addition of the extra fly also results in more snag ups, generally resulting in the loss of both flies. This can become quite costly when fishing streams such as the snag riddled Hinemaiaia, a tributary of Lake Taupo that receives excellent spawning runs of rainbow trout.
A buoyant indicator is essential with this form of fishing. As is setting the depth of the fly in relation to the indicator. If you can see your indicator bouncing along the surface, as your fly bounces along the bottom, rather than floating smoothly then you are fishing the right areas. This will require continual adjustment from pool to pool and run to run, but the rewards will be worth it.
The need for getting this correct was highlighted to me on a day fishing the Hinemaiaia last year. I had struggled for only a couple of fish for the day. Then I got chatting to a local fisherman who described how he had caught and released a dozen fish. He had a quick look at my set-up, handed me a handful of large split shot (size BB), and I was told to add a couple to the tippet. I then managed to hook three fish in quick succession from a pool where I’d been fishing for the past half hour without any interest from the trout. It highlighted the importance of getting your fly down deep as fast as possible to ensure longer drifts through the holding lies of the fish.
In general, fishing for fresh run rainbows is not a sight fishing proposition as it is when fishing to browns on their spawning migration. It is important to fish areas of the river where the fish are likely to hold and rest on their push up the river. Areas of slow flow, deep pools and long slow glides are ideal locations. It also pays to keep moving until you locate where the fish are holding. On finding a pool or section of river holding fish, slow down and cover it thoroughly. As with the browns, you can tackle many rainbows from the one section of river without spooking the remaining fish. When the fishing does slow down, rest the area for a few hours and come back to fish it later in the day.
The Lake Taupo fishery of New Zealand’s north island is most famous for its rainbow trout spawning runs and anglers flock from around the world to fish its stream mouths and tributaries during the winter. If you don’t like crowds however and want to fish the area, head there in April and May. Any rises in river level at this time can result in good runs of rainbows up the Tongariro, Tauranga-Taupo, Hinemaiaia and Waitahanui rivers. Fishing with the proven Glo-bug will result in some exciting captures of solid rainbows which really take some stopping.
A Personal Choice
As you can see, targeting migrating brown and rainbow trout requires a different approach for each species. Once brown trout enter rivers on their spawning run their behaviour is quite similar to resident river dwellers. Techniques normally used on resident fish will work equally well on running brown trout, with the added benefit of fishing to less spooky, fat, hungry fish. This combined with the large increase in fish numbers within the spawning streams make for dream fly fishing.
In contrast, rainbow trout on their spawning migration exhibit a feeding behaviour that is vastly different to those that reside in rivers. Rainbow trout that inhabit rivers have one eye permanently focussed on the surface and jump on any food items floating by. Running fish tend to sit close to the bottom and require a deep presentation with either a Glo-bug or nymph. This requires the use of a rather cumbersome to cast, heavy set-up. Glo-bug fishing is not to everyone’s taste. It will test the mending, casting and untangling skills of all fly fishermen. However, with a bit of patience and perseverance for the technique, you will hook onto some fish that are best described as silver rockets.
Both species offer something different and based on the techniques used it will be down to personal choice as to which species you wish to pursue. There is one certainty though, if you head out onto the rivers and streams with fresh running lake trout of either species, you can be assured of some days to remember.