Estuaries Of Southland

Nick Reygaert offers an insight into an underutilised New Zealand trout fishery

When most anglers think of New Zealand they imagine pristine waters that cascade off the high country and hold a few large, speckled monsters that suck down dry flies with seemingly reckless abandon. The reality is that this represents just a small portion of this wonderful fishery. To my mind, the most absorbing aspect of trout fishing in New Zealand is the fantastic variety on offer. The much-loved brown trout, commonly regarded as a fragile creature, is in fact an extremely resilient species capable of living under a variety of conditions. One only needs to investigate the extent to which the brown trout has thrived outside its endemic range to see how hardy and adaptable it is. Since their introduction to New Zealand in 1867 they have adapted so well that they have populated areas where they were never released. Sea run browns have made their way around the coasts and into some very remote river systems, far from the interfering hand of man. Southland, as the name suggests, is New Zealand’s southern most region and is well known for producing high quality trout fishing. However, most of the angling effort is concentrated on the upper reaches of the rivers that drain south along the alluvial plain. Rivers such as the Mataura, Aparima and Oreti are respected in angling circles and have a rich history of hatch-driven dry fly fishing. What flies under the radar of most anglers is the fact that trout exist in significant numbers right through the lower reaches and, often, out to sea. There are hundreds of miles of estuarine habitat in what amounts to a vastly underutilised fishery. KNOW YOUR TARGET Estuaries are a focal point for Southland trout, and during various seasons and life stages they represent a home, a larder and also a highway. During the last decade of fishing these environments I have learned that there are several types of trout present. These fish seem to have adopted particular lifestyles to fill different niches within the systems, and as a result need to be targeted in different ways. ‘Slob’ trout is an Irish term used to describe a brown trout that spends the majority of its time in the brackish water found in estuaries. I know of no other term to describe these fish and it seems to fit their physiology and demeanour rather adequately. Those that I’ve captured have all been well fed but lack the muscle and firmness of their sea-run brethren. By feasting on smelt and other small fish they have the rich, high protein diet of a sea runner but do not have to battle with the fierce currents and tides of the sea. They seem to prefer the upper reaches of the estuaries where there is less tidal influence but still an abundance of food. Also, undoubtedly, there are a number of riverine fish that descend the systems from further upstream during times of abundant food. These fish are similar in appearance to the estuary residents so it’s impossible to know the true extent of their numbers, but there is certainly an abundance of trout during the peak of the smelt run which leads me to believe that many river fish drop downstream to make the most of the feast. Sea trout or sea-run browns also inhabit the tidal zones of every river in Southland. They are brown trout that have spent a large portion of their lives in the marine environment. Sea trout readily move between fresh and salt water, often visiting a river’s tidal reaches in search of food. Any brown trout that has spent time at sea will develop a silver/chrome appearance and their spots will fade to the point where they resemble indistinct black crosses. These are strong fish and they fight like hell, often jumping several times. A Movable Feast Estuaries in the South Island and throughout New Zealand are subject to a number of seasonal migrations that provide a significant opportunity for trout to feed heavily. During late winter and early spring, the first significant event involves whitebait entering the systems on their annual run. The term whitebait is used generically by Kiwis to describe several species of diadromous native galaxias, hatched in the estuaries during large spring tides in autumn. The larvae are then flushed out to sea where they spend the winter months. As spring begins, especially after floods, the juvenile whitebait move inshore, drawn to the freshwater inflows from coastal rivers. This triggers a mass migration as vast schools of whitebait invade the rivers. Attuned to the whitebait runs, trout feed heavily on these protein rich morsels as they enter the estuary and move upstream. However, over the years I have come to view whitebait as the entrée rather than the main course of estuary fishing, much the same way as the trout do. Because, directly behind the whitebait run is a run of much larger smelt, migrating in from the sea to spawn. Locals netting whitebait for a feed are very disappointed when the smelt turn up because it usually signifies the end of the whitebait run. Smelt are not good to eat and have a rather strong cucumber smell — hence Southlanders calling them ‘cucumber fish’. Each surge of the tide pushes large schools of smelt up river as they search for suitable sand banks on which to spawn. They hug the shoreline where the tidal current is weakest. On the move and in unfamiliar territory, the smelt are exposed. Once again the trout are here, as that most adept of predators senses the makings of another easy meal. At these times I have seen brown trout working in teams to herd the bait schools and take turns in charging the mini baitball, often almost grounding themselves in their enthusiasm. This is a time of great plenty and the trout will feed aggressively throughout the day. In terms of fish numbers and action it is often the best time of the year for the angler, but the weather can be a real hindrance during springtime with fierce southerly winds roaring in from the Antarctic Ocean, bringing heavy rain and cold temperatures. Yellow-eyed mullet — sometimes called herring or sprats in Southland — also represent a significant prey item for estuary trout, especially for the larger fish. In summer and autumn the mullet enter estuaries in schools to feed and the trout in turn feed on them. Southland estuaries are also very rich in small crabs, and outside of the main baitfish runs these become a mainstay in the estuary trout diet. One of the best attributes of the Southland estuary fishery is that both sea trout and slob trout are present in good numbers in the systems year round. The water temperature in the estuaries and tidal lagoons is fairly constant year round due to the moderating effect of the ocean water that mixes with the fresh during every tide cycle. This influx of warmer water in winter keeps the fish fairly active during the cooler seasons and the estuaries of many of the region’s rivers are open all year, which makes for a good winter fishery. A bonus during winter is that the weather is often clear, with little wind — a welcome relief on this coastline! Estuary TACTICS Fishing the estuaries and lagoons can be a daunting task to the uninitiated. They are often large expanses and seem fairly featureless to those unfamiliar with these environments. However, the fish have the same basic needs as in the river — to eat and to be safe. They will be attracted to areas where they can facilitate these with the greatest ease. Luckily, small fish prefer the relative safety of shallow margins and this is where the trout will attack them, and so the best way to find fish is to walk the banks. Look for swirls or scattering baitfish as indicators of feeding trout. When fishing the upper reaches of the estuaries a floating line will suffice as the waters are uniformly shallow and the trout are rarely holding in deep water, especially during the smelt run when fish will be concentrated on the edges. It is really exciting to watch a trout charge down your streamer in only a few inches of water. I fish 10 lb tippet material, as I don’t think the fish can see it very well in the murky water and I prefer to have the pulling power. If your offering isn’t accepted first time, keep putting it in the zone — in tidal water these fish are not as skittish as their freshwater cousins and multiple presentations rarely spook them. Working The Tides It seems so unusual to be looking at tidal charts before going trout fishing but tide is the most important factor in determining trout feeding behaviour in these environments. Baitfish and crabs dominate the diet and the trout utilise the tides to expose these creatures. The best time to fish the upper sections of estuaries is either side of the high tide. Schools of smelt travel up river with the tide and the trout will be waiting to ambush them. Usually the upper estuaries have the highest concentrations of fish, being a mixture of riverine, slob and sea trout. However, I have rarely encountered larger fish in these zones, which is a mystery to me. An old-timer once explained to me that the larger fish prefer to target the mullet schools which hold closer to the estuary mouth, and that seems like a plausible theory. Hence, if you want to target larger trout the best place is closer to the river mouth. The hot spot is usually where the tidal flats drop into the main channel. The last of the run-out tide when all of the water drains off the flats and forces the mullet into the channel is the peak of the action. The predatory technique the trout adopt is similar to that used by fish in tropical estuaries. It is quite amazing to see brown trout rushing up a shallow channel and scattering baitfish in their path, much the same as a threadfin salmon or barramundi. Here you’ll need a sinking line to get the fly down quickly as there will be a lot of water ripping through. Bigger flies often work better in the muddy water and colour can be just about anything that will attract attention. My mate Jeff Foresee likes a massive, articulated, bright pink over white streamer, the same one he ties for taimen in Mongolia! These are big fish, and something that will get their attention in dirty water is what is needed. ESTUARY FLIES Traditionally the southern estuaries have been fished with streamer patterns like the Grey Ghost, Parson’s Glory and Hamill’s Killer. During my initial forays I used these time tested patterns and found them all to be successful. Recently I’ve been mixing things up with some modern patterns. During the last smelt run I was fishing a grey Manic’s Salt Candy in 3/0 to great effect. I also dabbled with small white Gurglers and took a number of trout with crashing surface strikes. Outside of the smelt run, the black Woolly Bugger is a consistent performer as is Chris Dore’s wonderful Dore’s Glister in size 4. These black streamers are a great imitation of the common bully (Gobiomorphus cotidianus) that is present in the lower reaches of these rivers year round. In the future, I intend to fish some small crab flies to tailing trout and I’m confident these will prove successful too. CHOOSING AN ESTUARY There are dozens of estuaries in the Southland region and all can turn on some great action at the right time of year. Major estuaries such as the Oreti, Waiau, Aparima and Mataura hold the largest biomass but many of the smaller systems can produce surprisingly large fish in certain conditions. The physical appearance of the region’s estuaries varies substantially. As a resting place for alluvial deposits, many of the large systems have extensive mud banks. Access can be difficult in these areas, particularly at low tide, and I use various styles of raft to reach different parts of each estuary. Other rivers, especially the smaller systems, have sand banks towards the mouth of the river in the short intertidal section. This allows easy access and often the action is hottest in this zone. Side branches off the main rivers also form coastal lagoons and these vary in size from small backwaters to fairly major systems in their own right. These lagoons often have large muddy areas and flax-lined banks, making access and movement difficult, but they often have great fishing. While it might not be the postcard New Zealand experience, fishing the tidal areas of Southland’s rivers does hold a certain appeal to the adventurous angler. Where else can you fish to big, healthy sea trout busting up schools of smelt, all under the watchful gaze of some Fiordland crested penguins?

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