Some Thoughts on Trout Fishing Management

 by Tony Orman

One winter morning quite a few decades ago, I took three trout on a Hawkes Bay river. Winter fishing had just been introduced. 

It was June and after using a deeply sunk nymph I had killed two of those three trout. As I landed the third – a fine jack rainbow –  milt came from it. It seemed right to return it. Catch and release was unheard of in those days too!

Thoughtful I  moved to the next pool upstream. I spied a hen fish vigorously digging her redd and there was an attendant male.

That was enough. I left the two trout. I packed up and with mixed feelings returned home. There I gutted the fish and found the two hen fish ripe with eggs.

I was fishing legally for the upstream limit was many kilometres upstream at a state highway bridge. But as I stood by the kitchen bench looking at those trout, there was a niggling thought that I had just literally killed “the goose that lays the golden egg.”

The point was those trout would have produced wild fry and fingerlings, which unless the periodic major floods occurred, were better equipped and suited to survival than hatchery reared liberated stock.

Winter fishing particularly in estuarine and lower reaches of big rivers has merit. But much further upstream, there seems little sense in catching trout that are about to spawn.

In recent decades, fish and game councils, formerly known as acclimatisation societies, have increasingly adopted  liberal policies. Winter fishing is now common. Method restrictions such as  “fly fishing only” waters has been removed. In Nelson-Marlborough for example there are now no “fly fishing only” waters. And liberations have been non-existent for decades now, with most hatcheries closed. The theory is it is better to rely on a fishery to be self-sustaining through natural spawning.

Excessive Liberations

On liberations of trout it would be fair comment to say that in the years of acclimatisation societies back in the 1940s, 50s and 60s, management was arguably guilty of carrying out excessive liberations of eyed ova, fry and fingerlings.

In some cases societies were accused of being political in merely trying to appease licence holders.

But it can equally be said that a blanket policy of “no liberations” as has applied since the 1980s and which was first proposed in a series of trout fishery reports by the then Agriculture and Fisheries Department, is just as meaningless and simply theory or ideology – dogmatically just too rigid.

Those department reports were based on a paucity of trout fishing diary returns and of a number of years previously when environmental conditions may have been much different to today. How can you base today’s  management on yesteryear’s results? How can you base management on such a small random sample?

In addition those reports consisted of very basic field work.There was little or no investigation of trout food such as bottom fauna samples and only a few drift diving samples which in themselves are not regarded in some quarters as accurate.

From this limited data, some far-reaching ideas were proposed by departmental officers sitting in their capital city centrally heated offices. Their message was clear – liberalise method restrictions and don’t liberate.

Such hasty thoughts are dangerous. I find it amazing that so-called experts would stake their credibility and reputation on such an insecure base and shaky data. But then, in fish and game history in New Zealand there has been more than one case of where experts were wrong and the layman sportsman correct.

Equally surprising was that fish and game councils accepted the liberal viewpoint towards methods and the laisse-faire (a philosophy of “don’t worry, leave it to look after itself”) policies.

Fisheries management is not a dogmatic exercise. It should not be a blanket policy of liberate everywhere or don’t liberate at all. 

Ecosystems

Each river is an ecosystem in its own right and may need individual management. Each season is different and brings with it different and sometimes extreme happenings such as floods or drought.

Therefore management should be flexible enough to consider each river’s character and needs and each season’s peculiarities. After all, you don’t farm on the West Coast as you would in Canterbury unless you compensate for the lower rainfall by sucking large amounts of water from public rivers.  Usually, management is quite different reflecting the contrasting natural environment and climates.

I remember many years ago talking to the late Alex Gilchrist in Hawkes Bay. Alex was a trout fishermen of immense experience and thoughtful and analytical.  Consequently he was a very accomplished angler.  His knowledge of trout fishing and trout fisheries although that of a layman, was based on solid experience and a mind not clutttered by theory or ideology unlike some expert bureaucrats who laid down dogma. 

Alex explained about liberations and trout in New Zealand. The trout’s natural habitat in Europe or the UK is one of severe winters. Now this can mean frozen lakes and ponds, snow falls and because there is little immediate run-off from the frozen countryside, streams run clear during spawning. Certainly they are usually not flooded and full of sediment like New Zealand ones can be.

“Here lies the crunch,” Alex said and went on to explain, “In New Zealand the winter floods hamper the natural spawning cycle, often washing out the redds or burying them under a metre or more of shingle.

“For that reason, we need to liberate some years. But it should be regulated and liberation requirements assessed and modified to meet the toll of winter floods.”

Nevertheless habitat is a key factor too. A strong role should be adopted to protect and enhance rivers and streams as trout habitat. Particularly today with threats like watershed monoculture of pines with their insatiable thirst, nitrate levels toxic to aquatic life and irrigation draw-offs.

Yet often fish and game councils and previously acclimatisation societies have turned a blind eye, or have simply been too short-sighted, to see threats to habitat. True the “dirty dairying campaign” by Fish and Game NZ although arguably ham-fisted and therefore provocative and unnecessarily confrontational in its approach, did rightfully focus on the detrimental effects from intensified dairy farming, water abstraction and the insensitive ruthless exploitation nature of corporate dairy farms.

Pine Monocultures

But what of forestry? Take the mono-culture of pine trees for example. This has been allowed to cover whole watersheds with a massive and visible effect on trout streams. Pines require a massive amount of water at the expense of the natural flow in streams.

In one Marlborough stream which I fished in the 70s and caught good fish up to 3kgs in, I returned 20 years later to be stunned by the lack of water. The stream was an estimated one third of its size, its water depleted by the acres and acres of pine forests. Today it is dry riverbed.

A once flowing trout stream – and spawning one -is now dry due to monoculture of pines

There is also a downside to pines in the establishment of exotic forests. The natural vegetation was cleared and the earth bared. Sometimes fires was used to clear. With the first rain came a runoff of water, soil and ash into feeder streams, often valuable spawning streams. Then 25 years later with the milling of the forests comes another bared earth phase and more runoff and deposition of debris into creeks and rivers downstream.

Why not mill a pine forest in a succession of alternating strips along the contour leaving a succession of unmilled pines which can then be logged in 12 months time after vegetation has stabilised the cut sections?

Why not zone land use to avoid monocultures of pines or vineyards?

Where were the vigilant fish and game councillors who should have been insisting on environmental controls and substantial buffer zones along important streams, as is common overseas?

From my observations of about four decades in total of serving on acclimatisation societies and latterly fish and game councils, too often, too little attention was (and still is) focused on the threats to the habitat of free flowing rivers. 

I recall one meeting – some years ago – where councillors spent more time debating whether to allow smoking at a meeting than to the effects of a monoculture of pines, a proposed hydro-electricity scheme or other development. 

In one bizarre case councillors debated long and hard that the firewood for a pot belly stove in a council duck shooting hut was to big for the stove’s opening but when I raised the threat of hydro-electricity development on trout rivers because of the Bradford power reforms and the issue of ill-conceived anti-firearm laws, while they did nod in agreement, there was no real interest, enthusiasm or concern. 

But firewood and pot belly stoves! That debate reached a height of dizzy vigour!

Meanwhile today, the monoculture of pines, a major threat to the flow and well being of public trout rivers, continues apace particularly with the ludicrous rort of carbon trading under the government’s Emissions Trading Scheme.

Increased Acidic

The existence of pine forests apparently also induces a chemical change in the water tending to turn it acidic. Now the healthier trout streams in terms of trout food such as nymphs (termed invertebrates) are alkaline. That’s why in the UK the chalk-streams running from limestone country are prolific trout streams because of the abundant food in the form of invertebrates.

The relationship of trout and trout food to alkaline or acid character suggests trout stream ecosystems can highly differ and usually cannot be reduced to single factors and simple blanket policy.  A blanket policy whether it be pouring trout liberations into all waters – or eliminating all liberations – cannot cover all shades of trout fisheries ecosystems.

The advocates of a no-liberation policy argue that returns from tagged or fin clipped fish are poor, about 1 percent it is said. That may be true or it may’ be that returns are poor because anglers cannot be bothered to notify of marked fish or do not notice them? Or are the number of surviving fish poor for just that water? Are eyed ova which cannot be marked, the better form of liberations? One very experienced and very respected angler-administrator the late Squadron Leader A G “Smithy” Smith of Nelson believed eyed ova to be the most effective of all forms of liberations.

In the 1950s the Wellington Acclimatisation Society poured hundreds of thousands of rainbow fingerlings into the Otaki River. They failed to establish. The society’s ranger the late Tom Andrews told me that when he liberated the juvenile rainbows at the Otaki Forks area in the mountains, he reckoned that by the time he drove back 25 kms to the state highway, the freshly released fish had beaten him downstream!

He explained that the stock from Taupo was a waste of time as the progeny of lake-living, river running fish had the instinct to disperse rapidly downstream. In the case of the Otaki the rainbows disappeared into the sea.

That suggests there is a futility in liberating fish which are not suited to the particular environment. In other words, trout of river-dwelling and not lake dwelling character, should be released in a river.

Similarly there may be a danger of undermining a genetic stock that has been derived over 100 years, by liberating juveniles from stock from another river.

If liberations are necessary, commonsense, logic and knowledge may be necessary to decide for a particular river if (a) liberations are needed and (b) if so, then it’s of the right stock.

Vibert Boxes?

I will dwell on Hawkes Bay because it is an area I fished over a number of decades particularly the 1960s, 70s and spasmodically through the 80s and 90s. When I went there in 1961 the trout fishing was simply superb. The Hawkes Bay Acclimatisation Society liberated heavily, admittedly not necessarily from wisdom but because it was the policy of decades before. But, inadvertently, they were on the right track in the case of the Tukituki, Maretotara and other alkaline-character rivers.

The superb fishing may have also been due to another form of liberation by way of vibert boxes where eyed ova is planted in little plastic cases in shingle. A project involving the local deerstalkers planted these boxes way up the backcountry in little feeder streams of major rivers.

The fishing for the next decade was magnificent. Was that due to those vibert boxes or was it just coincidence?

And on liberations it was interesting one time to hear the then NZ Professional Fishing Guides’ president Frank Murphy in an address to a conference say, “I’m glad no one told the European settlers, liberating trout was a waste of time.”