By Alina Suchanski

Reading time: 12 minutes 

With pristine lakes and rivers set amongst wild scenery, New Zealand is a recreational fishers’ paradise. Trout and salmon fishing have been lucrative tourist activities here for decades. But it hasn’t always been like that. Alina Suchanski tells the story of how trout conquered our waters.

The Southland town of Gore lies on the mighty Mataura River, still remembered for the 1913 flood, when trout would’ve swum through the town’s main street while the water flowed up to 1.8m high. As visitors cross the bridge over the Mataura, a giant statue of a trout greets them from the park in the centre of town. The sign next to it boasts “Welcome to Gore, World Capital of Brown Trout Fishing”. At the nearby tourist information centre, the reasons for this bold statement are explained to me as:

• Brown trout in New Zealand are much bigger than in other countries.
• We have a self-sustaining population of trout, while other countries stock their rivers with farm-reared trout.
• In comparison to other countries, fishing in New Zealand is affordable.
• Fishing in our country is safe because of the lack of dangerous predators such as bears in the USA and snakes in Australia.
• The Fish & Game access system to waterways is probably the best in the world. The Mataura River and tributaries have 80 access points, making it easy for anglers to find good fishing spots.
• A large number of mayflies on the Mataura River makes it the best river in New Zealand, if not the world, for dry fly fishing – the ultimate form of fly fishing.

Trout are a species of freshwater fish belonging to the family of Salmonidae. They are closely related to salmon. Of the two species of trout in New Zealand, brown trout, related to Atlantic salmon, were introduced from the United Kingdom, while rainbow trout, of the same genus as Pacific salmon, came from North America.

The importation of trout and salmon into Aotearoa’s fresh waters was part of a much wider movement to introduce British culture to this country, as evidenced in architecture, religion, law, farming practices, and food.

To make their adoptive country look and feel more like their motherland, European colonists formed Acclimatisation Societies to naturalise all kinds of species new to Aotearoa, without understanding the full consequences of their actions and the impact on native flora and fauna.

In 1867, the first of a series of animal protection acts was passed to provide protection to many of the introduced animals and to formally recognise Acclimatisation Societies in New Zealand. Later that year, the ingress of trout and salmon was enabled by the passing of “An Act to make provision for the preservation and propagation of Salmon and Trout in this Colony”, commonly known as the Salmon and Trout Act 1867. But it was a rocky road for both species.

Brown trout were introduced to New Zealand in 1867 from the UK via Tasmania.

In 2017, Otago PhD student Jack Kos, a keen fly fisher, wrote his thesis on the introduction of brown trout to New Zealand. He says that the early settlers thought of New Zealand rivers and lakes as barren and sought to improve on them by introducing fish species they were familiar with.

In an interview with Radio NZ in the same year, Dr Kos says that out of the 800 or so brown trout eggs brought from Tasmania, few survived. “Three of those eggs hatched, and then two subsequently escaped. At one point there was just one brown trout in New Zealand, but, rather remarkably, the two fish that escaped managed to wriggle their way into the Avon River in Christchurch and from there, two years later, they were recaptured. Huge numbers were introduced from about 1868 onwards.”

Under the animal protection acts, predators of valued introduced species were deemed to be ‘vermin’. Native black shags and eels preyed on juvenile trout, so Society staff trapped eels in streams and shot shags at known rookeries.

Atlantic salmon were the preferred fish that early Acclimatisation Societies really wanted to see in New Zealand rivers. What’s more, they had a strong preference to establish an anadromous (sea-run) Atlantic salmon fishery, rather than what they regarded as a second rate, landlocked one (Burgess, 2021).

Unfortunately, of the hundreds of thousands of salmon fry released into the waterways, a vast majority swam to sea, never to be sighted again.

The Societies persevered with importing salmon roe to the many hatcheries built around the country and releasing the fry into New Zealand’s waterways for decades.

Between 1910 and 1911, a million Atlantic salmon ova arrived in New Zealand. Almost all of them hatched and were released in Southland’s Waiau River, where they established a self-sustaining population. A further 494,000 young Atlantic salmon were released into Southland’s Aparima River (Burgess, 2021).

Atlantic salmon succeeded for a time in the Waiau River and Lake Te Anau during the 1920s and 1930s but eventually failed. Burgess says that they may, or may not, have been displaced in Lake Te Anau by later extensive rainbow trout liberations:

“Rainbow trout were released into the southern lakes in the mid-1920s. Up until that time, the landlocked Atlantic salmon population in Lake Te Anau appeared to be holding its own. In 1931, there was one rainbow trout caught for every three or four salmon; by 1948, it was the other way around. The rainbow trout in Lake Te Anau continued to do very well while the Atlantic salmon went into steep decline.”

In the 1950s, practices such as draining wetlands for farming, top-dressing with lime, taking water from rivers for irrigation, and river-damming were discovered to be detrimental to game-bird and sports-fish populations. Concerned about the effects of this land use on the health and sustainability of trout and other fish species, the focus of the Acclimatisation Societies shifted from protecting the introduced species to becoming increasingly involved in working to restore and safeguard their habitats.

In 1990, the Acclimatisation Societies became regional fish and game councils that, together, formed Fish & Game New Zealand. Funded solely by fishing licences, Fish & Game take care of the fish habitat, re-create wetlands, and assist with stream restoration. They are also champions of creating, building, and improving public access to waterways, often on paper (legal) roads.

Opinions about trout are divided. Conservationists see trout as a fast-growing active predator and competitor that eats native fish and invertebrates, including the freshwater crayfish or kōura, and directly competes with native fish for food (DOC, 2011).

But according to Bill Jarvie of Southland Fish & Game, trout are not a pest. They are a valued introduced species, protected under the Conservation Act 1987.

“Trout are the keystone species, an indicator of freshwater quality,” he says.

Jarvie admits that trout have had an impact on the New Zealand native species of fish.

“Kokopu, koaro, galaxiid, bullies, and kōura are largely gone due to predation and competition for food, but where we have a good quality, intact habitat, then we find co-existence of native and introduced species,” he claims.

Since its introduction into New Zealand, trout has always been highly regarded as a sports fish and has never been allowed to be sold as a commercial product within New Zealand. In contrast with salmon, trout farming is also illegal in this country. The importation of trout meat for sale has been prohibited since 1998 under a Customs Import Prohibition Order (CIPO) which is reviewed and renewed periodically.

Recently, there have been talks at government level of allowing trout flesh to be imported and sold in New Zealand. In 2018 and again in 2021, the CIPO for trout was about to lapse. Had that happened, the importation of trout for sale would have become unrestricted. However, the government yet again extended the import prohibition order.

On 5 July 2021, New Zealand Cabinet agreed that “it is in the public interest to continue the prohibition on the importation of trout and trout products for an indefinite period” (Customs, 2021).

Paradoxically, the sale of trout (except for wild trout) is theoretically allowed in New Zealand. The reason it is not for sale is because there is no way to obtain sufficient trout to sell. Trout farming, selling wild trout, and importing trout are all prevented by the CIPO or legislation, relating to the preservation of wild trout fisheries.

Another anomaly is that while Fish & Game look after the protection of trout and sell the fishing licences in most of New Zealand, the Taupo Region – a very significant part of the North Island freshwater fishery – is under the combined jurisdiction of the local iwi and DOC – entities which normally protect native species only.

Despite its environmental impact, the introduction of trout has had many positive outcomes. It provides food for some native species of birds and fish as well as for humans. Trout fishing is a hugely popular outdoor pursuit amongst Kiwis, and fly fishing tourism is a significant contributor to the country’s economy with an estimated worth ranging from $250 million to one billion dollars.

 

 

Sources: 1. Gamekeepers for the Nation: The Story of New Zealand’s Acclimatization Societies 2. New Zealand freshwater fishes. A natural history and guide. 3. Atlantic Salmon – Salmo salar – The strange and tragic story of Atlantic salmon in New Zealand 4. Key facts about freshwater restoration and eradication of trout and perch at Zealandia – Karori Sanctuary 5. Importation of Trout Meat and Trout Products – Regulatory Impact Statement 6. Five Customs Prohibition Orders

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