South Canterbury Trout and Salmon Fisheries Struggling

Opinion by Matthew Hall

The following is a submission by former Fish and Game NZ chairman Matthew Hall to the Central South Island Fish and Game Council about the precarious state of the regions fishery. The trend is not confined to South Canterbury           

Submission to Council about the sports fish resource.

This submission expresses concern about the poor state of the environment relating to the sports fish and game resource. The submission also ponders on the action that the Central South Island Fish and Game should take to highlight this disastrous situation. 

Statutory responsibility

Section 26Q (1) of the Conservation Law Reform Act provides the functions of each Fish and Game Council shall be to manage, maintain, and enhance the sports fish and game resource in the recreational interests of anglers and hunters and in particular, –
  1. Assess and monitor- 
(111)  the condition and trend of ecosystems as habitats for sports fish and game.

We currently know that –

  • The sea run salmon fishery numbers are at crisis levels.
  • There has been a huge decline in the sea run trout fishery.
  • Water quality and quantity in many low land streams no longer support sustainable fish populations and recreation.
  • Water quality in recent times in the Mid Canterbury high-country lakes have been classed as mesotrophic and a planktonic cyanobacteria bloom has caused health warnings to be put in place for Lake Clearwater.  Water contact recreation is not encouraged. Health warnings have also been placed on some rivers.
  • Ecosystems appear to be collapsing.

Some of us know the sports fishery we once had!

A standard phase of anglers at the Rangitata is ‘We have had the best of It!’

It would be possible to search out stats that could quantify the loss in sports fish populations in one generation (30 years).  The life of Fish and Game! This information would simply support what some of us know.

It would be a fair guess that only 5% of the coastal sports fishery now exists, compared with thirty years ago. If this trend continues at the end of the next thirty years (2050) there will only be a quarter of one percent of the 1990 fishery. In other words – “Nothing”

While Fish and Game has been measuring the trends in the populations that they manage the information is limited by the resources available to them to complete this work. Anglers catches and spawning numbers are only part of the story. Other agencies also have a responsibility to measure trends in eco-systems. The information about trends in the health of eco-systems is not in one place and is not necessarily complete. 

Sight Unseen.

Within reason the productivity of the resource can be measured. A much harder task is to calculate the factors contributing to change. Even harder still is to manage those factors. 
  • Years ago, we related an abundance of red cod to an abundance of salmon. Today it would be exceptional to catch a red cod off the Rangitata beach. We have reached a point in time where it is now exceptional to catch a salmon? Ocean conditions influence red cod populations which would suggest ocean conditions also influence the population of salmon. It is hard though to quantify the factors contributing to the decline in the salmon fishery at sea.
  • We know downward migrating juvenile salmon are lost in irrigation schemes and their productivity is lost to the sea run salmon fishery. Within recent times the proliferation of dead end ‘on farm’ ponds and the more efficient use of water must have added to the demise of the salmon fishery. The part this plays in the decline of the salmon fishery is hard to assess. One view is that this is the main reason for the demise of the Rangitata salmon fishery. A counter view is the fishery has for a long time lived with these losses.
  • The shoals of trout in coastal waters have disappeared, and we are left with the remnants of a fishery. Ocean factors play their part but from our work in the Hinds drains area over the last 30 years we know about the loss of productivity within streams. Being able to calculate the impact of a loss of water and available habitat is reasonably easy but add in water quality issues, weed growth and the impact of on farm practices and you have nightmare.  We know trout have disappeared; we know what has changed but to attribute the causes in a meaningful way crosses the boundaries that Fish and Game can manage.
  • We know trout are drawn to the coastal waters by the food resource. The food resource has disappeared so have the trout. The runs of smelt are only a shadow of former years. Of four trout I caught and gutted (3/4lb) during the November- December 2020 period, (coincides with the peak smelt run), the stomach content of only two trout contained smelt with five the most counted. One contained cockabully, and the other a single whitebait. Now this compares with a fist full of smelt, in each fish, in earlier years.  Why have the smelt disappeared, what is the impact on the trout population and other wildlife, and will the loss be permanent?

, South Canterbury Trout and Salmon Fisheries Struggling
The demise of the salmon fishery? Can it be halted?

Sight seen.
Science is the ‘The state of knowing’ and one would argue seeing is knowing!

We know there is a large colony of black billed gulls nesting on the spit at the Rangitata this year.

  • On 27th December 2020 I observed within my immediate vision in the bird colony, approx. 30 dead birds.
  • The stench of death was all around.
  • Care was needed not to stand on a corpse.
  • Grossed up over the whole of the colony there were hundreds of deaths.
  • The picture is of a well decomposed bird that was dead, but intact on 27th December 2020. The picture was taken on 9th January 2021 shows the rate of decomposition.
  • Of the live birds, on 27th December 2020 a number were having difficulty standing and some would fall over when you approached them. In a way they appeared comatose. The impression was malnourishment and possible disease. (Young and adults alike were suffering) Deaths continued over the following days.
  • It was easy to observe adult birds in flight coming in to roost. The young were calling, and the adults brought in no food. This was distressing to witness. The young were scavenging at a level I have not previously seen.
  • Hundreds of birds were lined the water’s edge, none were feeding. None were feeding in the wash at the river mouth or out at sea. There was no food, no smelt run, and this was plain to see adult birds and their young dying. 
  • The inclement weather prior to Christmas had put a stop to any smelt run and right through in to the New Year the smelt did not return in any number, even when the weather improved.
  • As the tide lifted over the river flats it would pick up the corpses and you could see them floating down the river and out to sea. The wave line was littered with dead birds.  
  • It has been surprising with scavenging, windblow and collection how quickly the dead birds disappeared.
For seventy years I have observed, photographed, and witnessed events in the bird colonies on the Rangitata River. I have seen them decimated by hail, by floods and by the sea but never have I seen the river fail to produce sufficient food for their survival. This was both alarming and distressing. To give the issue balance this year’s colony was one of the largest for some years. The issue though, was there was no food. A few adult birds were trading, but most were fixed to the shore line of the river or roosting on the river flats presumably waiting for the smelt to run. 
I was so concerned about the deaths I rang the Department of Conservation, Geraldine and the answer phone message said that all officers were on holiday and it would be several days before they returned to duty. If the officers were on holiday, they could not have witnessed the deaths or the lack of food. I suspect by the time they returned to work and visited the area they would view the remnants of the colony and would not be qualified to comment on the events that took place while they were away.
The statement in the Timaru Herald about finding large numbers of mullet and smelt in the hapua at the Rangitata during a survey needs to be put into context. I understood the survey of the hapua was in November and not in the weeks leading up to Christmas.  At times there can be huge shoals of mullet within the hapua because they feed on vegetative material and scraps that settles in the quiet water column of the hapua and these conditions suit them.  The eco-system suitable for a mullet is not the same as the eco-system suitable for black billed gulls. It is the smelt runs that are critical to the well-being of the colony and tens of thousands of smelt are needed to nourish the colony over the breeding season. The Department cannot translate a few hundred smelt noted in November to the state of the smelt fishery in December. My experience would suggest the run of smelt this season has been spasmodic at best and on any number of days non-existent.

The experience of the river’s failure to deliver enough food to nourish the bird colony to me was a new low in measuring the health of the river. Knowing birds were dying from malnutrition and perhaps disease was personally most unsettling. It follows there were no trout. Over the festive season very few salmon and trout were caught. The visual evidence of bird losses surely mirrors what is happening beneath the water’s surface and this is where sports fish once lived-in good numbers.

  • At the McKinnon’s Creek hatchery, a few kilometres upstream from the Rangitata River mouth, thousands of hours are spent by volunteers trying to save the salmon fishery. Save a fishery that has suffered harm done by others. Those cold winters days tediously attending to the eggs and fry, in challenging conditions of smothering algal growth within the creek, is a test of human fortitude. I look at McKinnon’s Creek today, particularly the lower section that is stained brown by aquatic weed growth and compare this with the way the creek once was. 
Visually the creek is not the same, there are rafts of brown scab weed and the water is the colour of cold tea. Most uninviting to any returning adult salmon. There must be water quality and quantity issues in this creek – Issues that are plain to see. The question is, is the creek tipping up and will the hatchery be sustainable going forward?
  • Lake Clearwater is another precious piece of paradise that is at risk.  A haven for anglers and holiday makers in a magical part of New Zealand. But is it?   The District Officer of Health has issued a warning that Lake Clearwater is the subject of a potentially toxic blue – green algae (planktonic cyanobacteria). Indeed, there was risk with water contact that skin rashes, nausea, and stomach cramps may develop. Ingesting algae may be fatal to dogs. For some time, the mats of weed in Clearwater have been an issue and the fears are the lake could turn eutrophic and the consequences to fish life would be disastrous.

  • All the Ashburton Lakes have been bracketed as ‘At risk’ and this is not a healthy sign for the future.

Fish and Game can do as much internal soul searching and audits as they like, they can have a prize set of standing orders and governance policies. They can have space age rules regarding conflicts of interest and eject those conflicted in to space or to the next room or wherever but what they cannot do is control the resource the statute requires them to manage. They must point the finger at others and have them recognise they are killing the sports fish and game resource.

Fish and Game has a function under the Act to manage, maintain and enhance the sports fish and game resource yet they do not control the resource therefore their ability to manage the resource is limited.

What Fish and Game can do is attach conditions to fishing licences that will help manage harvest by anglers? Sec 26R (4) sets out the conditions Fish and Game may apply.
While it can be argued that there has been material benefit to fish populations with the increasingly restrictive conditions placed on anglers over the years, populations have continued to decline this affirming that the cause of the decline is outside Fish and Game’s control. 

  Below is a table that sets out a layman’s stab at factors that influence fish populations. 

Factors influence fish populations.

(With ten the most influential.)   – Rating the control by Fish and Game.

Controlling factor
Rating out of ten
Dry rivers or low flows. (Inadequate minimums) 
Rivers polluted by towns 
Adverse farming practices including pollution.
High weed growth and eutrophication
High nutrient levels (nitrates)
Damage to spawning grounds 
Fish lost to river systems (Abstraction)
Diminished river resource through irrigation 
Silt in rivers
Angler catches 
Predation by fish, black shags, and birds
Control over food source 
Control over the ocean environment – (By catch)
Climate change and global warming 
Section 7 and the RMA

Note – A mark of one out of 10 is given to the effectiveness of Fish and Game’s advocacy role.       
Advocacy Role – Section 26S (7)
This section of the Act gives the Council the statutory power to be heard on matters affecting the fish and game resource and indeed on any of its functions under the Act. This includes promotion and education.

Matthew Hall MNZM

26th January 2021

, South Canterbury Trout and Salmon Fisheries Struggling

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4 Responses to South Canterbury Trout and Salmon Fisheries Struggling

  1. Tim Neville says:

    What an asset this man is to angling. It is well researched, accurate and well put. Congratulations to him for his courage. Anybody with only 10% vision who crosses his region will see for himself that the rivers have all been stolen.
    Tim Neville

  2. "Pheasant Tail" says:

    The John Key regime and his ‘un-environment’ conservation minister Nick Smith with their manipulation of ECan was disgraceful and did irreparable harm to the public’s river and the aquatic ecosystem. Not that Labour and David Parker are setting a scorching pace to repair the damage.

  3. Tim Wakefield says:

    Sad reading that rings very true matthew

  4. Peter D. Trolove says:

    Mathew Hall has written an excellent submission to the CSI F&G council.
    He has reported what many anglers know – that the once outstanding recreational fisheries that existed at the mouths of Canterbury’s large braided rivers are no more. He has made it very clear that it is the role of F&G to respond.
    Presently F&G are undergoing a much needed governance review. Once this is completed and the organization can work effectively again it is hoped we will see some meaningful action on behalf of license holders who fund F&G to manage these fisheries.
    On behalf of the NZFFA thank you Mathew.
    Peter Trolove President.

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