Reminder….

Trout Centre Kids’ Days -

• Wednesday 24 July 2013
• Wednesday 9 October 2013
• Sunday 27 October Labour weekend
• Wednesday 8 January 2014
• Wednesday 22 January 2014

 

DOC Media release

Date: 27 May 2013

Winter fly-fishing season gearing up

With the trout spawning season and the air of expectation upon us, it is now time to re stock the fly box and blow the dust off the fly rod and reel.

Anglers and Boaties having noticed the improved summer fishing are now awaiting what should translate into better fishing on the spawning rivers of Lake Taupo. Although still early in the season, good signs are appearing on the Hinemaiaia and Waitahanui streams with small numbers of fresh run rainbow trout being caught in the lower reaches. Nymph flies such as green caddis, hare and copper and glo bugs tending to be effective at this early stage whilst rabbit flies and woolly buggers have given wet liners some success when the river levels have been up and water clarity coloured.

 

An increased number of anglers are always to be expected during the winter fishing season so as a reminder to all seeking the thrill of a screaming reel, general angler etiquette should be extended to others. For the uninitiated, angler etiquette for the Taupo Fishing District is:

 

• When up streaming nymphers meet down streaming wetliners, the angler first in the pool should be given right of way.  No one fishing method (nymphing or wetlining) has right of way on the river.
• Avoid entering the river in front of an angler already fishing without their consent. Likewise give the edge of the river a wide berth if an angler is fishing that stretch of water to avoid spooking any fish.
• If you are sharing a pool keep moving through steadily. Continue to rotate positions through a pool, this allows all anglers opportunity to fish the better spots.  Also take note of the method of fishing as this will avoid potential conflict with others by minimising unnecessary tangles or spooking fish.
• Allow other anglers room to play a fish. It’s always best to give others space when they have a fish on. Wait until they have exited the pool before continuing. It is good etiquette to allow that angler to return to their position after landing their fish.

 

On the river bank common courtesy will go a long way and can lead to some good discussion on the conditions of the day. Successful anglers are more likely to pass on good advice if we give each other room to enjoy the fishing.

The winter fishing limits for the Taupo Fishing District will be in place and are:

Upper river sections close 1 June to 30 November.

Lake Otamangakau closes 1 June to 30 September

Lake Kuratau closes 1 July to 30 September

Don’t forget, Check, Clean and Dry all fishing gear when moving between waterways. Help protect your rivers and lakes from the spread of Didymo and other fresh water threats.

ContactsKim Turia, Programme Manager Community Relations,

Department of Conservation Taupo-nui-a-tia,

Ph (07) 384 7163 [email protected]

 

Date: 27 May 2013

Summer Catfish monitoring provides valuable information.

The Department completed another summer of catfish monitoring on Lake Taupo and successfully removed close to half a tonne of catfish between November and March using fyke nets set overnight at three separate locations around the lake. Catfish were accidentally or deliberately introduced to Lake Taupo during the 1980’s and DOC has monitored the catfish population to determine whether they are having a direct affect on the trout fishery.

A total of 2,637 catfish were netted from the lake over summer from Waihi, Motuoapa and Whakaipo Bay. This equates to an overall catch rate of 35.6 catfish per night, per fyke net which is close to the annual average of 38. Motuoapa produced the most catfish with 51% of the total catch followed closely by Waihi on 45% and Whakaipo with just 5%. Historically, Waihi has tended to produce the most catfish but perhaps the lower lake level this summer and subsequent warmer waters amongst the shallows pushed the catfish out into deeper waters as catches weren’t as high as expected especially towards the end of summer. The distribution of catfish is influenced by suitable habitat around the lake shore.

Overall, catfish averaged 231mm in length and 184g in weight which is slightly above the annual average. The stomach contents of both small and large catfish (>250mm) were examined separately to determine what these catfish were feeding upon. As expected from previous analysis, small catfish consumed largely plant material (67% of total diet) and snails (22%) with larger catfish also preying on these items but also containing some koura (13%) and small fish (11%). No actual smelt were identified amongst the stomach contents of over 500 catfish examined. An additional sample of larger catfish was gathered by spearing them during the day off the Tauranga Taupo River mouth to better understand what larger catfish prey upon. The predominant item found in these larger catfish was plant material (30%) followed by small bullies (27%) and koura (20%). Once again no smelt were identified amongst the stomach contents.

The majority of the dead catfish were donated to Awhi Farms (Turangi community garden) and turned into fertiliser and compost minimising the wastage and putting these pest fish to a good use. With the odd catfish now showing up at the river mouths at night, anglers are encouraged to humanely destroy any catfish that they catch.

Annual events such as the Spearfishing NZ Lake Taupo Catfish Cull and the Blue Light Trade Zone Gone Fishin Day provide avenues to control catfish populations as well as providing sport for spear fishing and angling enthusiasts. The February Spearfishing Catfish Cull produced 975 fish over the day.

The Department will continue to monitor the catfish populations next summer and will help remove these unwanted fish from Lake Taupo.

Photo caption: Catfish Cull competition produced 975 fish this year.

Photo by Anna McKnight

 

 

Contacts

Mark Venman, Programme Manager Field Operations,

Department of Conservation Taupo-nui-a-tia,

Ph (07) 384 7158 or [email protected]

 

DoC’s Fishery report: April 2013 update

Fresh run rainbow jack caught on the lower reaches of the Waitahanui river

Te Whaiau Stream fish trap

A total of 19 rainbows and 72 browns were trapped during April in the Te Whaiau Stream fish trap (the main spawning tributary of the Lake Otamangakau fishery).

It was good to get some rain to stir things up but only 200 mm of rainfall was recorded at the trap site this month and was spread evenly throughout the month.

The number of rainbows trapped this year is on par with April 2012 but the number of browns trapped is down on last year by nearly 30 fish. However, it is still early days and the runs of both species will increase significantly during May with the brown trout run expected to peak then.

Number of trout trapped in the Te Whaiau Stream fish trap during April 2013 

Waipa Fish Trap

The Waipa Stream fish trap (situated in a tributary of the Tongariro River near Rangipo) was installed for the season during early April and trapped a total of 36 trout over 22 days. The majority of these fish were rainbows with only 5 brown trout being trapped. These browns averaged 569 mm in length and 2.3 kg in weight ( 5lb) with an overall condition factor of 44.8. The heaviest brown trapped was a jack weighing in at 2.6kg (5.7 lbs). The rainbows averaged 475mm and 1.35 kg (3 lbs) with an average condition factor of 45.2. The heaviest rainbow trout was a 2.15 kg (4.75 lbs) jack in great condition.

The overall improvement in condition this year is very encouraging as the fish still maturing in the lake will be continuing to feed and grow before the main spawning runs occur in late winter or early spring.

Number of trout trapped in the Waipa Stream fish trap during April 2013 and daily rainfall recorded

Lake Taupo

The lake has still remained a popular destination for anglers during April and the relatively settled weather during early April contributed to this.

During early April, the lake continued to fish well to those jigging especially around the northern end of Lake Taupo. With the onset of colder weather and stronger winds, the lake will start to mix and the thermo-cline will start to break up meaning that the fish will prefer to be in the top 20 metres of water and in reach of more traditional methods such as deep trolling with lead lines.

Harling during the early hours of the day or just before dark is also a good option to pick up a nice pre-spawning fish during May. Areas such as the lake front off Waitahanui should fish well to harling in the morning during May.

Based upon what we have observed and measured over summer, the lake should continue to produce well conditioned fish over the next couple of months when the weather allows. Please remember that when jigging, trolling or harling, you must stay more than 300 metres away from stream and river mouths marked by the white, yellow and black marker poles on the lake shore as these are designated as fly-fishing only areas.

The calm and settled weather this summer has been favourable for jigging with 43% of anglers interviewed during March alone using this method. More anglers have got into jigging this summer and have done well all around the lake. With the lake still relatively warm, fish have been caught deep between 25 and 45 m. Jigging has been the ideal method to target these deeper fish. Drop-offs and deeper holes fish well and areas such as Wharewaka Point are currently worth a go.

Lake Otamangakau

Due to the exceptionally dry summer Lake O was commonly referred to as “Lake Low” this year due to the low lake level and minimum flows throughout the system. Getting to some spots proved difficult but fish could still be located in holes and open areas amongst the weed beds with some nice fish in the 5-7 lb range caught.

With one month left before the lake closes to fishing for the season, fish will be starting to congregate in areas such as the canal and Lake Te Whaiau prior to running the Te Whaiau Stream to spawn. If we get some decent rain over the next few weeks, the fishing can be expected to be very good in these areas as these pre-spawning fish prepare to run.

Tongariro River

With the runs starting to slowly filter through the Waipa Stream, the Tongariro will have fish spread throughout although mature fish won’t be present in any great numbers at this early stage in the season.

The lower reaches of the river downstream from the Bridge Pool down through to DeLatours would be worth a look early in the season and it pays to keep moving if you are not having much luck until you find a small pod of fish. Wet lining through the lower reaches is well worth a shot and you stand a good chance of hooking a nice brown trout at this time of the year especially with woolly buggers or dark rabbit flies.

Anglers have generally been spread throughout the river searching for fish and the first decent amount of rain during mid April didn’t have too much affect on the river.

Prior to the rain, the Tongariro Delta had fished well as early running trout had started to congregate and with many of these fish having moved into the rivers, it has slowed slightly. With a more settled weather pattern occurring and frequent showers forecast, the Delta and other river mouths will be worth a fish during May. Larger fish tend to run the rivers early in the season so give them a shot during the day or night.

Summary

With the winter spawning runs still in their early days, the signs that we have seen so far through the Waipa trap, for example, are very encouraging. These rainbows are averaging 3 lbs in weight and with some fish approaching close to 5 lbs, it will be interesting to see whether the fish yet to enter the rivers, continue to grow well and put on condition over the next couple of months.

We are still expecting the runs to be late again this year with a large proportion of the run expected in spring but the next decent rain should produce some sport for those anglers keen to get an early taste of the winter fishing.

Based upon the fish we have seen this summer we are expecting some great fish in the rivers this winter.

Remember check clean and dry all gear before moving between rivers and lakes. Stop the spread of didymo and protect your waterways.

 

Date: 15 April 2013

Netting of Prime Breeders a Loss to the Fishery

A sharp eye and swift communication led to the recovery of a gill net in Lake Taupo at the mouth of the Waitetoko River last weekend.

Keen eyed anglers who had intended on a spot of fishing spied the net set at the mouth and quickly passed on the information to DOC and Police. Both agencies attended the site and the net was recovered. It had been set in the mid afternoon and within three hours had caught eight mature trout and two juveniles. All of the mature fish were in prime condition and at least two of the fish, which were large brown trout, would have been superb breeding stock. Unfortunately they didn’t get the chance to carry on their passage upstream to spawn.

“All anglers look forward to the spawning season, which appears to have already started.

It’s a shame that some people continue to target this time of the year to set or drag nets, in and around the spawning areas, therefore catching and killing good potential breeding stock and causing damage to the spawning grounds” says Jill Larsen Welsh- Area Compliance Officer.

DOC will continue to monitor areas of interest at this time of year and will prosecute those involved in this type of illegal activity. Netting or spearing trout are offences against the Conservation Act 1987 and can attract maximum penalties of, a fine up to $10,000 or a term of one year imprisonment. The Department considers this type of offending to be serious and will do their best to ensure those engaged in these activities are caught and prosecuted. A big thanks goes to those people who pass on information in such a timely manner, enabling DOC staff to respond immediately – your help is invaluable.

Vigilance by river and lake users is important in trying to tackle this problem. Any information received is treated in confidence and with seriousness, and where possible follow up action is taken. If you see anything suspicious please contact the DOC duty officer- 0274424962.

Photo caption: Trout gained through illegal means.

Fishery report: April 2013 update

Graham Hamilton with his recent catch
at the Tongariro Delta

Lake Taupo

The fishing during March has continued to be good with anglers catching an average of one legal-sized trout for every two hours spent fishing. The overall catch rate between November and March was 0.37 fish per hour (one legal-sized fish every two hours 40 minutes) improving on previous years.

Rainbow trout kept by anglers during this month averaged 463 mm and 1.24 kg (2.75 lbs) with an average condition factor of 44. This is an average increase of 11 mm in length, 200 g in weight and a better overall condition than trout caught during the same period last year.

The calm and settled weather this summer has been favourable for jigging with 43% of anglers interviewed during March alone using this method. More anglers have got into jigging this summer and have done well all around the lake. With the lake still relatively warm, fish have been caught deep between 25 and 45 m. Jigging has been the ideal method to target these deeper fish. Drop-offs and deeper holes fish well and areas such as Wharewaka Point are currently worth a go.

Jigging should continue to be good during early April as the thermo-cline is still intact. Fish should also start to congregate around the river mouths from now, especially if some decent rain is finally forecast.

Boat anglers are reminded that they must stay 300 m away from the centre of the river mouths when trolling or jigging (as indicated by white, yellow and black marker poles).

Taupo Fishing Club competition

It was encouraging to see some very well conditioned trout being weighed in at the recently held Taupo Fishing Club competition. A well attended event showcased the quality and quantity of trout still avaliable late in the summer season. The best condition factor rainbow, measured in the early 60s. Angler satifaction measured high as well.

Forecast

Making the most of the abundance of smelt present this summer, trout will continue to feed prior to running the rivers to spawn this winter. If the trout currently being caught on the lake are any indication, fish running the rivers this winter should be in great condition and in good quantity. Rivers such as the Waitahanui and Hinemaiaia are known to see early runs of rainbows with some fresh run fish in the 3-5 lb range having already been caught from the Hinemaiaia during late March. The first decent flood this season should also encourage more fish into the other eastern tributaries and kick off the spawning runs for another winter season.

Anglers are encouraged to make the most of the settled weather and great fishing on the lake but it would pay to check through your fly-fishing gear and tie some new flies as this winter is expected to be a good one on the Taupo rivers!

DOC Fishery Report for March

Date: 21 March 2013

Great Lake, great place for fishing.

Anglers fishing on Lake Taupo this summer have experienced some of the best fishing for sometime as the trout have been abundant and in great condition. The long and settled weather has also created ideal boating and fishing conditions for those venturing out onto the Great Lake.

This summer the overall catch rate collected from anglers surveyed, was 1 legal sized trout every 2.5 hours. This is a vast improvement on the 1 fish every 3.5 hours from previous years.

Mark Venman, Programme Manager for the Department of Conservation says “Trout have not only been more plentiful this summer, but they have been larger, heavier and in better condition than last season continuing an improving trend observed over recent years within the Taupo Fishery”.

Having made the most of the improved smelt numbers, trout caught over the past month have averaged 461mm and 1.14kg (2.5lbs) with an average condition factor of 42.2. The fish kept by anglers overall this summer have averaged 452mm and 1.1kg with a condition factor of 43. Again an improvement compared to last summer.

“It has been encouraging to see some very well conditioned fish in the 1.5-2kg range (3.5-4.5lbs) appearing amongst angler catches. Anglers certainly seem much happier this summer” Mark says.

This all bodes well for the Easter break and upcoming winter fishing as trout will continue to feed and grow prior to their spawning runs (April to November). Anglers can expect good fishing by jigging or down rigging in depths over 30 metres. Any significant rainfall will start to push spawning fish into the rivers over the coming months. Rivers such as the Hinemaiaia and Waitahanui will be worth a look early in the season.

Make the most of the settled weather forecast for Easter and enjoy some great fishing!

 

DOC Fishery report: February 2013 update

Ranger Grant Sim holding his catch

Lake Taupo

Fishing on the lake has continued to be good during February as the fine weather and light winds continue to dominate. The estimated catch rate for February was 0.29 legal-sized fish per hour (1 fish every 3 hr and 25 min) which is on par with January. Good numbers of trout are still being caught with some larger fish noticeable amongst the catch. The condition of the trout has certainly improved over recent years and this summer is shaping up to be one of the best for some time.

Jigging around the western bays has been particularly productive especially around Whanganui and Waihaha in depths of 30 to 50 m. The headland at Motuoapa has also fished well to those jigging. Rainbow trout kept by anglers and measured during surveys throughout February averaged 456 mm and 1.1 kg with an overall average condition factor of 42.8. It is encouraging to see some nicely conditioned fish around 500 mm in length and 1.5 – 1.7 kg in weight appearing amongst angler’s catches.

Smelt are certainly more noticeable around the sandy shores this summer with large shoals of them evident along the beach at Hallets Bay in particular. Trout of all sizes are making the most of the abundance of smelt and continue to grow by approximately 30 mm per month while feeding entirely upon smelt. With many fish not spawning until spring, river anglers should be able to catch some great fish this coming winter.

Lake Otamangakau

The warm and settled weather has certainly got the insect life active at Lake Otamangakau but the low inflows and the subsequent low lake level has made fishing difficult for some anglers. The trick has been trying to find some open areas amongst the weeds and finding areas where colder water flows in. Some really well conditioned fish around 6 lbs in weight have been caught this month and the lake should fire up again when we finally get some rain. There is still quite a lot of surface activity in the evenings at Lake Otamangakau for those seeking some dry fly action.

Tongariro River

The evening rise on the Tongariro has quietened down slightly as this month has progressed and, despite the warm days, the evenings have started to cool down slightly and the rise has been shorter than expected. Some very large browns (3 – 4 kg) are starting to make their way up the Tongariro River and have been caught throughout the middle reaches of the river both during the day and at night. Rivers such as the Waitahanui will also contain good numbers of fresh run browns at this time of year.

Forecast

Good fish are continuing to be caught on Lake Taupo during early March and the lake should continue to fish well to those using deeper methods such as jigging and downriggers right through until after Easter. With some nice fat fish currently present in the lake and winter just around the corner, it is shaping up to be a solid winter of fishing on the Taupo rivers.

Auckland Waikato Reel Life Feb 2013

Big rainbow bonanza

Huge rainbows are in abundance throughout the region.

A mild exaggeration for sure, but there’s no doubt that this is an exceptional year for rainbow trout in the King Country rivers.

In previous seasons, a 2kg rainbow would have been considered an outstanding catch in the Waipa catchment (e.g. Mangatutu, Puniu) or in one of the west coast rivers (such as Awakino or Mangahoi), but this season catching a 2kg-plus rainbow is becoming commonplace.

The most likely explanation for this large fish bonanza is that the wet, cool summer we experienced last year provided superb feeding opportunities for trout.

So there’s no better time to go fishing in the King Country than now!

Heading off with high expectation.

Summer drift dives

Drift dives have been carried out in only two rivers so far this season, but further dives are planned for late February/March on the Awakino and Whakapapa rivers.

The Waihou River was dived in late January. This is a pristine, spring-fed river with a reputation for holding large numbers of fish in crystal clear water.

In recent years the upper river has been fenced off allowing the watercress and reeds (Glyceria) to grow out from the bank, so angling has become more challenging. Nevertheless there are still extensive sections where it is possible to wet-wade or fish from the bank.

On the dive we saw reasonable numbers of large fish (over 40cm, 15 per km), and indeed some of these fish were really impressive looking rainbows of 2.5kg-plus.

Medium rainbows (30-40cm) were plentiful at 30 per km, while smaller fish (20-30cm) were abundant (160 per km).

The Waihou is a classic dry fly river, in the tradition of the English chalk streams, and you can have a lot of fun on a hot summer’s day fishing with small dry flies such as royal wulffs.

We’ve been discussing with the Waikato Regional Council (WRC) the possibility of removing Glyceria from along the upper Waihou River. It is a noxious weed and very susceptible to sprays.

We’re also discussing with WRC their plans for willow removal along the tributaries of the Waihou, and how angler access can be improved.

Rivers such as the Oraka Stream contain good trout fisheries but only short stretches of water are accessible to anglers, as most of this water is choked with willows and the banks are infested with blackberry.

 

Fishery report: January 2013 update

January summary

Tongariro River

Alec Corfield’s fine catch on Lake Taupo

Alec Corfield’s fine catch on Lake Taupo.The long and hot days during January provided some great hatches on the Tongariro River during the warm and still evenings. The Tongariro still holds good numbers of fish recovering after spawning and it shouldn’t be long before some large browns start showing up throughout the middle reaches. Likewise, rivers such as the Waitahanui should also see runs of brown trout enter over the next couple of months. With the lake starting to warm and hit the early twenties, a visit to some of the river mouths should be worth a look - trout start to seek the colder in-flowing waters as they continue to feed and prepare for spawning this winter.

Lake Taupo

Fishing on Lake Taupo has been very good during January with an overall estimated catch rate of 0.32 fish per hour (1 fish every 3 hours). Jigging was the preferred method on the lake during January and accounted for 43% of all anglers and 54% of the total legal sized catch. A total of 61 rainbow trout kept by anglers throughout January averaged 455 mm and 1.15 kg (2.53 lbs) with an average condition factor of 44.1. Overall, anglers kept 56% of their total catch and released the remainder with undersized trout accounting for 28% of the total catch.

Smelt numbers have started to increase with some good catches recorded at Hallets Bay and Omori. It was encouraging to see some larger smelt in amongst the catches made during late January and numbers of smelt are expected to increase over the next couple of months. The trout caught around the southern end of Lake Taupo have had stomachs full of smelt and some fish have been seen spewing smelt when brought alongside the boat. The improvement in the overall condition of the trout also points to a better smelt season.

Jigging has been very productive during January especially at the southern end of Lake Taupo in the Tokaanu Hole and off the Motuoapa headland. Successful anglers have targeted the trout in water between 15 and 25 m (50 to 80 feet) drifting from the deeper water into the shallows using a sea anchor to slow down the drift. Keeping in contact with the bottom has been the key and ensure that your dropper length is not too long (i.e. 100-120 mm long is ideal). Small green matuka style flies have been working well along with fluorescent yellow bodied flies. Not a lot of action is required to give the flies movement when the dropper length is shorter. Anglers can expect fish to go even deeper during February and so depths of 30-35 m (100-120 ft) would be worth a go. Jigging can be a lot of fun and very effective if done right but please return any unwanted fish to the water carefully. Some fish may need to be supported in the water for a few minutes while they recover from being brought up from deep. Juvenile trout are also starting to show up in numbers and care should be taken when releasing these undersized fish.

Downrigging has also produced some good fish especially along the Waihi Cliffs at the southern end of the lake. Check your sounder for large clumps of smelt that show up like bait balls and take note of what depth that they occur. Lower your downrigger ball to that depth and troll a lure through the smelt layer. Smelt were showing up during late December at 18-25 m (60-80 ft) in water as deep as 55 m (180 ft). Any of the coloured cobra lures seemed to work and the depth fished seemed more important than the colour of the lure.

More traditional methods such as harling and shallow trolling still work well at either end of the day but as the sun comes onto the water the fish tend to drop deeper and so jigging and downrigging become more productive as leadlines struggle to get deeper than 20 m. Harling has been going well for those fishing before sunrise with some nice fish being caught off Waitahanui.

Motuoapa fishing contest

The Motuoapa fishing contest held during mid January saw close to 100 rainbow trout weighed in averaging 453 mm and 1.1 kg (2.42 lbs). These fish had an overall condition factor of 42.5. The heaviest fish weighed in was a hen measuring 560 mm and weighing 2.34 kg (5.15 lb). Almost two thirds of the fish were caught deep trolling, with jigging and shallow trolling accounting for 23% and 14% of the remaining fish weighed in, respectively.

Forecast for February

The lake fishing should continue to improve over the coming months as the fish continue to grow. Deeper methods such as downriggers and jigging will improve your success as the fish seek the deeper and colder waters as the surface of the lake starts to warm and stratify. If you have given up fishing Lake Taupo during recent years, give it another shot this summer and you might be pleasantly surprised!

Please continue to ‘Check, Clean & Dry’ your fishing gear and boating equipment if visiting from another area to minimise the risk of spreading didymo or other unwanted freshwater weeds.

 

(Thanks to Peter Shepherd from DoC who approved TRM reprinting the following feature article from Target Taupo  – published December 2012 as TRM still get many complaints and questions about the earthworks project between Reed Pool and Delatours.  Read on…)

Gravel extraction in the Tongariro River – not something new

By Mark Venman
Fishery Operations Manager
and
Lawrie Donald
Zone Manager Taupō River and Catchment Services
Waikato Regional Council

The lower Tongariro River has seen considerable change over the past couple of years, with both the removal of willows and the more recent removal of gravel and sediment downstream of the State Highway 1 (SH1) road bridge. Concerns have been raised that this work has had a detrimental effect on the fishery by removing cover for juvenile rainbow trout and adult brown trout through habitat modification, but has also impacted on anglers through the loss of fishable water such as The Braids. This article summarises what work has been done and looks at what is planned for the future and what this means for both fish and anglers.

The Tongariro River catchment spans an area close to 800 km2 and consists of several tributaries flowing into the main river channel before discharging into Lake Taupō, approximately 10 km downstream of Turangi township. The river itself is approximately 92 km long and carries sediment such as volcanic ash, pumice and andesite lava from the eastern slopes of the volcanic central plateau plus greywacke, argillite and ash from the Kaimanawa Ranges. The Tongariro River undergoes significant channel changes in response to natural events such as floods and volcanic eruptions. The natural hydrology of the Tongariro River has been significantly changed by the Tongariro Power Development diversions, with average flows in Turangi almost 50 % less than before the scheme. Large flood events remain relatively unchanged but the scheme does curtail flood recessions and this can impact on the natural movement and deposition of sediment throughout the lower reaches of the river.

The township of Turangi is located at the head of an alluvial fan created by the Tongariro River as it approaches the Tongariro Delta and Lake Taupō. The bed of the Tongariro immediately upstream of Turangi consists of coarse cobble and boulders. Heavier material, such as cobbles and gravel, gets deposited at the upstream end of the alluvial fan while lighter sand and silt is transported through the lower end of the fan and down through the lower reaches as the river slowly meanders towards the Delta. This deposition of material at the head of the fan is a natural process and, over time, this deposition process will raise the flood plain and cause lateral instability of the channel, that is, the river will spread over a wider area. Waikato Regional Council is required to manage this process and stabilise the path of the river to protect property and life in Turangi from floods.

Flood control works have been established over many years, with work dating back to the late 1950s. During the 1960s and 1970s, approximately 700,000 tonnes of gravel was removed from the river in the vicinity of the Swirl Pool. Since the removal of gravel has stopped, the artificially lowered river bed has acted as a sink for bed load material coming from upstream during floods and has filled in this area to the point where it has now returned to its ‘natural’ level. It is thought that this natural level could be the upper limit for management of the flood control scheme.

Waikato Regional Council has constructed a flood protection scheme on the Tongariro River within Turangi Township to protect property and people from the equivalent of a 100-year flood. Protection is provided by the formed floodway, which includes stop banks, river channel, river banks, berms and flood plain. The scheme consists of stop banks for flood control, with erosion control structures to ensure that river banks remain stable. With the river’s higher bed level, there is a risk that the current flood protection measures are not sufficient to handle a 100-year flood. It is hoped that the combination of willow removal, continued gravel and sediment extraction and a widening of the flood channel will ultimately result in Turangi surviving the next 100-year flood.

The most recent work commenced in 2011/12 to remove scrub and willow infestation from the floodway to help reduce the peak height of a 100-year flood, as water can flow more easily to Lake Taupō without the risk of backing up and flooding Turangi. A large part of this area has been mechanically cleared and followed up with spray to minimise regrowth. Further work is required to continue to eliminate willows and other woody species from the floodway. Woody species, such as broom, buddleia, grey and crack willow, colonise gravel islands and can cause the river to divert during a flood due to reduction of the cross-sectional area of the river floodway. This vegetation needs to be cleared prior to any gravel or sediment removal. With continued woody vegetation management, vegetation cover in the form of grasses and toitoi should dominate over the next 3–4 years. River bank erosion could become a problem through the clearing of willows and the development of a wider channel but this will be monitored.

Some areas of willow have been strategically left in key areas to minimise the risk of the Tongariro breaking out and cutting a new channel into Stump Bay during a significant flood event. A blind channel approximately 1 km in length and still growing has developed from the lake towards Turangi. It is this channel that carries flows during floods and there is potential for a permanent breakout from near Delatours Pool and Awamate Road to join up with this channel and threaten a number of waahi tapu sites.

From a fishery perspective, the willows in the lower river provide cover for both brown and rainbow trout residing in the lower reaches. The dense root systems are also an ideal nursery for juvenile trout as they grow and migrate down towards Lake Taupō. Summer fishing in the lower river was also largely terrestrially based, with anglers using large cicada patterns to hungry browns and recovering rainbows busily feeding under the cover of the willow branches. Much of this cover has been lost, but some areas of willow have been left to help stabilise erosion-prone areas that will provide some cicada action in the short term. The Department of Conservation (DOC) is also advocating for a small section of willows to be left along the edge of islands downstream of the Crescent Reserve to provide suitable habitat for fish. It is possible that this work could encourage browns to reside further upstream and closer to the town pools. With browns entering the Tongariro from late December onwards, it will be interesting to see where the browns choose to seek cover this coming summer.

Gravel and silt extraction has already commenced, and this work has really changed the landscape especially on the true left side downstream of the Crescent Reserve. This site is currently devoid of any vegetation, but it is anticipated that the completed works will result in a much more pleasant experience for those visiting the river. The cleared floodway will be managed as an area free of willows and other trees and shrubs and be dominated by indigenous plants, such as toitoi, once a full season of vegetation control and establishment has occurred. The improved access and the re-establishment of vegetation over the spring and summer periods will hopefully increase angling enjoyment once the area returns to a more naturalised state.

A new flood channel has been opened up down the true left side of the river to move the river away from the true right side during significant floods. Vegetation has been removed and the area widened so that the river can spread out laterally during a large flood. This new channel was created from an old groundwater channel and continued down towards where the Hirangi Stream enters the Tongariro on the true left bank, just upstream of the Reed Pool.

After discussions between DOC, Waikato Regional Council and the Tongariro River Advocates during early July 2012, it was decided to reduce the normal permanent flow down this channel to encourage more water down the true right side and ultimately into the Bain Pool area. With a bulldozer already on site, the machine went to work to achieve this. We discussed collectively what the options were to create more braided water and add more diversity to the channel to make it less uniform and canal-like for both anglers and fish alike.

One major concern we had was the presence of large willow stumps half buried in the soft sediment down to a depth of almost 2 m that were still in the new flood channel making angling almost impossible due to snags. The new narrow channel certainly looked good from an angling perspective, if you ignore the stumps, and fish were present soon after it was created. We discussed the option of using the bulldozer to cut channels from this flood channel through to the centre river channel to increase the flow down the true right side and into the Bain Pool and create some diversity and braided channels. It was difficult to know where to make these channels and the river will generally decide where it wants to go during a major flood event.

Fortunately, we only had to wait 4 days for a 620 cumec flood to come down and rearrange the river downstream of the Crescent Reserve! We thought the work done by the bulldozer was impressive but the Tongariro proved who was in charge and made a few changes to the flood channel and the volume of water now flowing down the true left. The widened flood channel on the true left worked well and the river sent a considerable flow down the new channel and across the flood plain on its way to the lake. A significant volume of water still came down the true right into the Bain Pool area but that has reduced as flows returned to normal. Some nice braided water exists still near Tongariro Lodge and around the Bain Pool and it will be interesting to see how it fishes during the spring. The small flood channel on the true left is now much straighter and wider than before and looks very fishable if you can see past the snags.

There is a lot of fine gravel deposited in this channel and with minor modifications could be both fishable and ideal juvenile trout habitat.

As it is currently, there is slightly too much water flowing down the true left flood channel for both adult and juvenile trout but with minor modifications, this channel could offer a lot more. DOC is keen to reduce some of the flow by cutting channels into the island and diverting water through to the centre channel to increase the flows into the Bain Pool. Some willows left along the side of the island will help provide cover and shelter for trout of all ages. Combined with rock groynes, it will naturally become a diverse area for both fish and anglers.

The weekend of 25 and 26 August 2012 was one of the busiest for anglers this winter throughout the Tongariro, but especially downstream of the SH1 bridge. Anglers could be seen fishing right down past the Crescent Reserve area and were hooking fish in this newly modified landscape. The area just downstream of where the bulldozer had previously redirected the flow is producing fish and has been referred to as the new ‘Honey Pot Pool’ by local anglers. Since the July flood, the head of this stretch of water has looked ideal for nymphing and brings in a nice flow. Similarly, a nice area for anglers has been created where this true left flood channel re-enters the main channel at the head of the Reed Pool. This is suited to both nymphing and wet lining.

Work proposed by Waikato Regional Council for the next 3–5 years will focus on managing the expected in-coming deposition of sand, silt and gravel in the vicinity of the Swirl Pool area. The vegetation management completed to date has helped to establish the freeboard required for a 100-year flood flow to pass through Turangi without breaching the current stop banks. Modelling by Waikato Regional Council based on the most recent surveys has indicated that the lowering of the flood plain through this section has re-established the design flood protection scheme freeboard.

The removal of gravel that has built up in the vicinity of the Swirl Pool is planned for the future as this will lower the mean river bed level and subsequently increase the floodway capacity at this location. Some vegetation clearing is required upstream of the SH1 bridge and will be done mainly using chemical sprays rather than mechanical means. Vegetation that restricts the floodway will be dealt to. No extraction of gravel is required through this reach as the stop-bank freeboard is currently sufficient to deal with a 100-year flood. It is hoped that this level of intervention in the river will be a one-off with future maintenance work minor in comparison. However, this will naturally be dependent on future flood events and the deposition of material. Essentially, the rest of the river will be left to its own devices unless there is serious erosion or significant deposits of sediment that need to be addressed. The riprap rock wall at Herekiekie Street also requires a small amount of work to top up the structure and reduce its steep gradient. This will require the river to be diverted away temporarily from the true right while the work is undertaken.

DOC is keen to work alongside Waikato Regional Council to get a balance between flood protection work and the interests of the fishery, and the council has been very receptive to our concerns and requests. Gravel extraction is not something new to the Tongariro River and if done sensibly can create new angling opportunities and trout habitat as well as keep the people and property of Turangi intact.