Wednesday, July 6, 2022

Shaping up for a good season

When a trout fishery declines, whether due to floods or drought, lack of food or poor fisheries management, it is three years before concerns are raised and measures taken to restore the fish stocks, or before they restore naturally.

That's the time taken for spawning which supports juvenile recruitment to the mature stocks that will spawn again and again and so improve the numbers.

It was 2008 when the Taupo and Turangi areas suffered 13 floods and it has taken until 2012 before fishing conditions have returned to ‘normal’. Catches this spring indicate that fish quality is up on the previous season, as is size. There have been a range of measures taken to ensure that this happened.

The size limit was reduced from 45cm to 40cm so as to reduce the numbers of fish sharing the limited amount of food in the Tongariro catchment area.

That may seem a perverse measure to increase stock size but the result is quick growth of healthier fish that are heavier spawners and so after time both size and quantity improve. There has been work on improving river mouth runs such as the famous Waitahanui. The willows that lined the lower reaches of the Tongariro have been cleared to improve access for both fish and anglers.

In August the Department of Conservation (DOC) released 5000 one-year-old rainbows at the deltas of the Waimarino, Tauranga-Taupo and Tongariro Rivers and at the Bain, Blue and Birch Pools on the Tongariro. Each fish was marked with a coloured dye to identify the site of release if they are recaptured in coming years. The intention is to try to kick-start the runs of fresh rainbows from Taupo into the rivers earlier in the year. Old-timers will tell you the runs used to be thick in June through to August; now the major spawning runs don't occur until September-November.

The fish released were all taken from Lake Tarawera, which has a reputation for producing the first spawning fish of the season in the central North Island. There has been concern from locals that introduction of these fish will impact on the quality and quantity of those in the later runs. DOC said it has evidence from overseas fisheries that indicates that won't happen. But it will be three years before anyone really knows because it will be at least two before the dyed trout start turning up in catches and the total catch surveys provide proof one way or the other.

Jared Goedhart, trout expert at the Turangi Sporting Life store, said the fish coming from the Tongariro River this spring are in good nick, with a mix of sizes. Boaties have had a good winter on the lake and that looked set to continue, he said.

Trolling with the standard traffic light and spotted gold lures had been working well. For fly-fishers, there had been mayfly rises in the day and caddis in the evening to liven things up. Some good browns had been taken in the Tongariro he said, along with the fresh-run rainbows.

"The measures taken to improve things have worked all right. The balance has come back to normal.”

Smelt runs have been promising, much stronger than for the past few years, which should encourage good growth in the spent fish that are returning to the lake. At the time of writing, all methods were working on Taupo from deep jigging and trolling to harling in the shallows, as well as early morning or late fly-fishing. This will change as the shallows heat up and the bigger fish seek cooler climates in the deep, when the lakeside fishing will be best dawn and dusk. The catches coming out of the Rotorua lakes since opening day last month suggest it's going to be a good summer there too.

Surveys by Fish and Game show that the average size of the two-year-old trout in all the lakes is larger than it has been for some years, with the average around 1.7kg in Lake Rotorua and Lake Rotoiti and up to 2kg at Lake Okaitaina, though catch rate is lower.

In the Wellington area, too, anglers can look forward to a good summer without having to travel too far.

Drift-dives on the Hutt River and tributaries found there had been significant improvement in the trout population throughout all reaches of its waterway. Fish were seen spawning in areas where they have not spawned since the big floods of 2004.

Over the past winter there has been a big upsurge among South Island anglers in the use of soft-baits to target trout. The method has proved very effective for those who have perfected the cast-and-retrieve, either on fly-lines or by spinning.

Effort put in on Lake Dunstan and the Clutha River has been well rewarded. They seem to be better in faster-flowing water than in the narrows and shallows.

It’s essential to match the size of the soft-bait to the size of the jig-head and also to position the bait correctly on the hook so as to achieve the right 'wiggle' in the water. Soft-baits with the chunked tail section flattened at the end seem to work better than other shapes but according to what I've heard colour makes little difference, though some say the darker greens and browns are best. Interestingly, anglers I've spoken to reckon they have attracted more regular hits and hook-ups when fishing through the day than they would have using flies and nymphs on the rivers, and an increased hit-rate also when trolling soft-baits as opposed to the usual Tobies and other solid lures.

Soft-baits require work to master and, as with any new fishing method, will take a lot of experimentation and trial and error before you'll work out what works best. But given how they have taken off in saltwater fishing it's sure they'll become part of the scene.

I've always believed that you can't have too many arrows in your quiver: On the salt, the soft baits work when other rigs won't and likewise, other rigs with baits work when they are less successful. If you're not catching fish, change something, is my motto.

Snap a snapper

It's work-up time on the saltwater for those who target snapper. As temperatures rise towards the 18degC required for spawning the snapper are congregating in large schools, feeding up aggressively in preparation for the sexual exploits of the coming months.

Snapper are serial spawners and will produce eggs from now through to March. Sometimes these aggregated schools can be located by following birds, which feed on surface baitfish, sometimes by following schools of dolphins which have better sonar that any fishing boat, and sometimes by the fish-finder as low red lumps rising from the seafloor.

Anchoring can be a real hassle when chasing these fish, which move to swallow the bait, wherever that goes as it is herded and panics. Drift-fishing is the go. The snapper may be 100m or more behind the surface action where kahawai, kingfish, dolphins and sometimes marlin or whales might be spearing through the balled-up bait. Running through the school may send it down. Trolling often produces nothing because the predators are feeding on small fish and this is particularly the case with surface-feeding trevally. It’s best to predict the direction of travel, get ahead and then stop. If wind is pushing the boat along too fast, use a drogue. Almost anything should pull in fish when they are feeding like this, from baited ledger rigs to metal jigs and soft-baits. The biggest fish may be taken on a whole live-bait.

That's also true for the trophy-size snapper that run up the West Coast each year. Geoff Preston, who lives at Mokau and launches his Mac360 off the beach if the bar is uncrossable due to tide or swell, reports that the huge reds arrived in September and by mid-November he was still sending me pictures of his latest 10kg-plus snapper. Preston uses a strayline rig with whole fresh baits or fresh strips of kahawai on large hooks, which is a good rig anywhere for big fish.

The schools of big reds head up the coast to Auckland and Northland each year and by the end of December they're gone.

There may soon be efforts to restore the vast mussel beds that used to cover the floor of the Firth of Thames and lower Hauraki Gulf. These beds were dredged out of existence in the 1950s-70s. Clearing of land and subdivision that went on at the same time greatly increased the flow of siltation into the Firth and the younger mussels found it impossible to survive once the solid beds of mature shellfish had been taken.

But now marine scientists have found that mature mussels planted in patches can gain a foothold on the seabed and and that they provide a three-dimensional habitat in an otherwise flat environment, so they then collectively attract barnacles, sponges, seaweeds and then crustaceans, small fish and eventually larger predators including snapper.

Research has shown that large species that grow on the seabed, including green-lipped and horse mussels and the sponges that live with them, increase local biodiversity by providing complex, three-dimensional habitat in an otherwise flat environment.

"They provide attachment surfaces for algae and immobile invertebrates, refuge for small mobile vertebrates, foraging areas for adult fish and probably act as important nursery habitats for juvenile fish," marine biologist Dr Shane Kelly said in a report commissioned by the Hauraki Gulf Forum.

"High-density populations of mussels can filter vast amounts of water, they produce phytoplankton as food for other species and they keep the water clear. Historically, the original untouched mussel beds could have filtered the entire volume of the Firth of Thames in less than a day; the remnants left now would take nearly two years to filter the volume of water in the Firth. Mussel harvesting is estimated to have reduced production by small mobile invertebrates by up to 33,000 tonnes/year (dry weight), which would have supported as much as 16,000t of small predatory fish (wet weight).

Kelly's report to the Forum has attracted much interest from marine biologists, and Forum manager Tim Higham said some prominent researchers were looking at a collaborative project to take the idea forward. There have been two meetings of interested parties and a trust has been set up to raise funds so the idea can be progressed.

Off limits

November 1 marked opening day for the smaller central North Island lakes including Otamangakau and Kuratau. Forestry work will be conducted around Otamangakau over the summer and anglers are warned not to breach 'Road Closed' signs when these are in place. There have been breaches of this in the past, and the forestry owners have warned they will close all access past the boat ramp if it continues.

The majority of South Island rivers opened on October 1 and the southern lakes area of Otago on November 1, with anglers reporting good catch rates across the lower half of the island. Lake Dunstan and the Clutha have been fishing well as have the small back-country Otago lakes. As usual, dawn and dusk have been best times. There have been good insect rises but high wind has made it hard for the dry-fly fishers and nymphing or spinning has been the more productive way to ensure a catch.
That should change as the more settled summer weather arrives.

Off home after this

An old sea captain was sitting on a bench near the wharf when a young punk rocker sat down next to him. The young man had studs in his face and spiked hair, with each spike a different color … green, red, orange, blue and yellow. The young bloke sees the old captain staring at him. "What's the matter old timer, never done anything wild in your life?" he says.
The captain replies, "Got drunk once and married a parrot. I was just wondering if you were my son".

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