Championing truth to distinguish fact from opinion

Final speech by Lachlan McKenzie as Federated Farmers Dairy Chairperson at Federated Farmers Dairy’s Annual General Meeting at the Distinction Rotorua.

Kia Ora.

Please accept my warm welcome to my home town of Rotorua to our delegates and guests.

This is my final address to you as chairperson of our great industry group, Federated Farmers Dairy.

As is traditional in a final speech and without fear of a voting backlash, I wish to speak on championing truth to distinguish fact from opinion.

In this speech I wish to examine three common statements to establish if they are fact or someone’s opinion.

The first is that, “trout have no effect on our water ways”.

The second is that “we need to control nitrogen loss from farms in order to stop increased nuisance algae or periphyton growth”.

And, finally, “but river water quality is declining”.

I told you, I won’t be pulling my punches.

“Trout have no effect on our water ways” – or are they freshwater stoats?

According to the Invasive Species Specialist Group’s list of the world’s 50 most invasive fish species, Rainbow Trout is number 26 and Brown Trout is number 47.

You may have to look at trout in a whole new light as stoats, by way of comparison, are number 22 on the mammals list. Both trout and stoats are highly successful predators not native to this, the Southern Hemisphere.

While one is hunted as a terrible pest, the other is protected in the RMA and even has a hatchery on Department of Conservation land.

Trout can significantly impact our native fish, amphibians and invertebrates. As trout expand to new streams and rivers, actively aided by one body under statute, they squeeze native species habitat to less preferred areas or water bodies.

When introduced trout are about, native fish, research has shown, struggle.

Native fish are out competed for habitat and for food. As our native fish are out of sight, does that mean they ought to be out of mind too?

When you cannot hunt for your food, eventually it becomes terminal and this can collapse aquatic biodiversity.

But let’s look at what I feel is the biggest impact of trout.

Huryn, in 1998, compared algal biomass in streams with invasive brown trout and those with our native freshwater fish species or galaxiids.

This research found that the algal growth you and I see in our streams was six times higher in water that had invasive brown trout in it.

This is what I see as the most important implication.

In the streams with trout, only about 21 percent of the algal growth was eaten by invertebrates because trout devoured nearly all of the invertebrates. I’ll say that again, only 21 percent of the algal growth was consumed in streams with trout. If you were an invertebrate in that stream, your life expectancy is almost zero.

Compare this then to those streams that had native fish. Three-quarters of the algal growth was eaten by these invertebrates while less than one in five invertebrates were predated on, in turn, by native fish.

With trout present, net algal growth explodes by well over a factor of three and within the same water nutrient quality.

The little critters that graze algae and keep it in check have almost no life expectancy with trout present. Without trout, algal growth is kept in check and our streams and aquatic biodiversity achieves balance.

The implications go much further and deeper.

Trout infected waterways have greater sensitivity to nitrogen and phosphates due to increased nutrient recycling.

So the statement that trout have no effect on our waterways is simply not true. For that we only have to look at Koi Carp, the twelfth most invasive fish species. In some lakes and rivers the biomass of Koi Carp is like having two dairy farms per hectare, except trout and Koi Carp live in the water.

Yet two of the 50 most invasive fish species are on a legislated pedestal with protection in excess of that given to native fauna and flora.

We have jaundiced freshwater ecologists blaming land based industries, when they should be looking at what is eating the basis of the food chain unbalancing our native aquatic biodiversity. It’s much easier to blame farmers if you happen to be running a separate agenda.

We can easily and graphically see the effect of stoats, possums and rats on our terrestrial environment. Like night vision cameras capturing the death of a Kiwi chick, but what if we have an equally disastrous species in our waterways devouring native invertebrates, increasing algal growth and forcing our native fish to the brink?

It’s time to test if trout is the benign tourism friendly icon it is held up as, or if it is in fact, an aquatic stoat.

“We need to control nitrogen loss from farms to stop increased algae growth”

All farmers and gardeners know that given sufficient light and temperature, the growth of plants is controlled by the concentration of nutrients, particularly phosphate and nitrogen. It’s as applicable to pasture as it is to brussel sprouts.

Having been on the Land and Water Forum for a while, I’ve learnt something of the science of water quality.

In the aquatic environment, water is held to be nitrogen or N-limiting, phosphate or P-limiting or actually, a mixture of both

I want you to remember this as I talk.

The higher the level of a limiting nutrient, the larger algal populations will result until their growth is limited by a lack of nutrients.

In 2009, research from the New Zealand Journal of Marine and Freshwater Research reported 1100 fresh water sites monitored for over a decade, by our regional councils.

Seventy-six percent or 836 sites tested were P-limiting. I’ll repeat that; over three-quarters of these sites were phosphate limiting.

As a limiting nutrient is an element necessary for plant growth, once a limiting nutrient in water is used up, plants or in this case, algae, stop growing.

Meanwhile, given the fixation with nitrogen, 12 percent or 132 sites were actually nitrogen or N-limiting. An additional 132 sites or 12 percent were both nitrogen and phosphate limited.

Phosphate limiting is head and shoulders the most common scenario in New Zealand freshwater. We are talking 76 percent of streams with phosphate limiting, but less than a quarter that have any form of nitrogen limiting.

Any call from Government, from Dr Mike Joy and from councils to control nitrogen loss by hook or by nitrogen capping crook, is at best, well less than a 24 percent solution.

As dairy has for a long time played close attention to recycling nutrients, where are these phosphates coming from?

Surely not from hundreds of billons of litres of wastewater enriched with phosphates from shampoo, soap and detergents. Surely not from introduced aquatic fish and water fowl either?

The fixation with nitrogen is a big hammer to take the cork out of a bottle while leaving the contents untouched. Here in Rotorua the biggest impact on the lake is phosphates from well over a century’s use of it as a big oxidation pond for the town and its visitors.

The facts, as reported by the New Zealand Journal of Marine and Freshwater Research, speak for themselves.

“But river water quality is declining”

Farming affects water quality, yes, but we seem to have been attributed with 100 percent of the blame.

According to a NIWA report on nuisance periphyton growth at national river water quality network sites between 1990 and 2006, it found and I quote, “Analysis of trends in annual mean and annual maximum periphyton cover during 1990-2006 found more sites with decreasing cover than increasing cover. This encouraging finding was not expected given the increasing agricultural intensification…..”

I think I need to do a double take with that last sentence; “This encouraging finding was not expected given the increasing agricultural intensification…..”

I interpret NIWA’s report as saying they assumed there would be more algae growth but the reality was the opposite.

Last November, another NIWA study into lake water quality found 40 percent of lakes with ‘dominant native catchment cover' had declined in water quality. These are native lakes so could it be introduced water fowl, koi carp, aquatic plants, trout or even

Last November, another NIWA study into lake water quality found 40 percent of lakes with ‘dominant native catchment cover' had declined in water quality. These are native lakes so could it be introduced water fowl, koi carp, aquatic plants, trout or homosapien perhaps?

Federated Farmers Dairy into the future

Delegates, I have given you just three examples where opinion is not supported by the facts yet assumed causes and assumed links are actively driving policy.

As I leave the chair of this organisation, I ask you all, as you continue into the future, to please separate opinion from fact. Ask the where, what, when and how questions before formulating responses.

Do not fall into the trap of assuming that qualifications make a person impartial because we are human beings with human failings. Bias is as natural for a person with a PhD as to someone without one.

Don’t accept someone’s opinion on a solution as gospel but interrogate it and check it out. If robust it will stand scrutiny, if not, there is cause for concern.

Farmers have been reticent to debate and that’s been to our disadvantage. We’ve let claims go unchallenged and in the minds of some members of the public, the lack of challenge means those claims must be true.

Bad science is not science, but opinion dressed in impressive clothing.

While I was using environmental examples, there are many economic opinions that need debunking. Milk being too dear comes to mind when Statistics NZ has shown that it’s been much more expensive in real terms in the past.

As representatives and spokespersons for our organisation you have to ensure that with our skilled staff, the facts are understood and communicated. The truth is the truth and must be told and retold for eventually, it does get through so long as it is championed.

If not you, whom then?

My final few words

I have enjoyed and learnt from the many experiences that I have had as your representative and chairperson.

I would like to thank the executive for all the support and work you have all put in. I will miss the team spirit we have built.

I wish to thank the Federation staff and especially Ann Thompson. No more last minute reminders and reports being worked on overnight to be delivered by an 8am deadline.

I wish you all, Federated Farmers Dairy and my successor all the best for the future.