I wrote recently about the need not to react with alarm to scaremongering about the claimed poor state of Noosa River’s biodiversity from NBRF and Noosa Council. That was exaggeration, not science.
NBRF and the Council need to develop an systematic and scientific regime for all studies over time so the studies are consistent in terms of methodology. Then, if significant variances are identified, they need to pinpoint causality (the reason why) if this is required. In my opinion, the failure to commit to such an approach will result in lengthy, haphazard and costly projects which are likely to be ‘hit or miss’ in terms of actually fixing the root causes of issues if and when they are identified.
I have been sensing over the past year an increasing wave of effort moving to the next phase of of ‘Bring Back the Fish’ (BBTF) which is about ‘Restoring Prawn Stocks in Noosa River and Lakes’. My mind conjured up images of millions of prawns released into the lakes under the glare of media attention, the satisfied faces of the plan proponents and the smiles of a faithful public who have given their free time to steward processes by those in control.
It brought back reminiscences of a similar situation in the Swan and Canning Rivers of Western Australia on a project that started five years ago. River Guardians (a WA Government program that engages the community on matters relating to the Swan and Canning rivers) developed a project called ‘Prawn Watch’ which engaged the Perth community in monitoring prawns in the Swan Canning Riverpark.
The project encouraged the sustainable management of the estuary and fishery through data collection, information sharing and awareness raising. It recently received a commendation in the Environment category at the 2017 WA Seafood Industry Awards. All fantastic and how things should be!
Over the course of the four-year project, 4.5 million juvenile prawns were released into the Swan and Canning Rivers. The project, investigating the factors limiting the natural recruitment of the Western School Prawn, engaged the community in monitoring the recreational fishery.
What they did there, and what is very much needed in Noosa, is data. For example, each month in the WA project, researchers measured both inshore and offshore waters, the correlation between various physio-chemical variables, benthic layer composition structure, food sources and more – which is not happening here and won’t happen unless a structured research regime starts now and we allow several years to correctly gather the required data. This is a world away from declaring the Oyster Trial a success after 11 months!
The background of the WA project was:
Both M. dalli (an estuarine species) and the Western King Prawn Penaeus (= Melicertus) latisulcatus (a marine species) were the focus of a small commercial and iconic recreational fishery in the Swan-Canning Estuary before catches declined significantly. The commercial fishery, which had a peak catch of 15 tonnes in 1959, closed in the mid-1970s and recreational fishing, which involved >50,000 people in the 1980s, also declined, with the last significant catches recorded in the late 1990s.
The reasons for the decline were unclear and restocking was seen as a possible means of increasing the population size of M. dalli in the estuary. The two restocking projects enabled the development of new aquaculture techniques for M. dalli and subsequent releases from 2012 to 2016. These were linked to Prawn Watch and the community was engaged in restocking efforts. This project provided the funds to undertake the research and development side of the restocking, enhance our understanding of the biology and ecology of M. dalli and the subsequent monitoring of the population post-release of hatchery-reared individuals.
Some of this starting to sound familiar?
It should come as no surprise why there is such a strong push here to have fishing licenses for the Noosa River – in other parts of Australia revenue generated from these licences seeks to turn back the clock. Over the first three years of the WA project, more than $330,000 was committed to restocking prawns in the Swan River.
Despite good intentions, today we have no hard scientific evidence that prawn numbers in the Noosa River have permanently fallen. Are recent results an anomaly? We don’t know. Has there been some adverse environmental impact? We don’t know. Do we honestly understand what is happening? NO – we don’t.
Several months ago, in an interview with Dr Tweedly, who led the Murdoch University/Swan River Trust part of the WA project, he stated that between 2013-2016 researchers released 4.6 million juvenile prawns and, with delight, watched as the crustaceans multiplied. Everyone was happy and many proudly declared the project a success.
Continuing, Dr Tweedley stated that the Swan River was then hit by two unusual weather events – a cold winter that sent water temperatures two degrees lower than normal and an extreme downpour in early 2017. The upshot was that today the prawn population is back to where it started.
So Mother Nature has won and returned the Swan back into equilibrium with what is today and not the past. By this I mean the effects of urbanisation and other environmental events dictates our destiny despite all good intentions and efforts.
I am in no way wanting to sound defeatist. I just want to emphasise that, given how much we have changed the physical landscape over time, it is pure fantasy to expect that we can return to historical levels (that is, the way things were before we populated and impacted an area) and then sustain that situation. What we can do is adapt to what is today and planned for in the future. Improve things and be more conscious of our environmental footprint and then set realistic expectations for balanced outcomes as opposed to idealistic outcomes. This, in my view, is the way forward.
The Noosa Council, NBRF and NPA do not have a monopoly on caring for the environment. I believe all Noosians deeply care about our special place. I have long held the belief (and have made public submissions and written letters to the Mayor on this) that we can have all the great environmental projects we like and throw countless dollars at them, but unless some fundamental issues are addressed it is a bit like sticking a band-aid on a shark bite.
Through my research of many works that pertain to the Noosa River, I have came across comments and researchers’ recommendations to Council from pre-eminent people who say that we need to better understand the impact of the changed river mouth. If there have been declines in fauna and flora over the last 50 years, what role did this major shift play in altering the biodiversity – and what further impact will it have in the future.
In their work ‘Assessment of status and options for recovery of prawns in the Noosa River Estuary’ Associate Professor Greg Skilleter (University of Queensland) and Professor Neil Loneragan (Murdoch University) state from the outset:
‘The Noosa River estuary and lakes system is considered to be a relatively unmodified estuarine system although it flushes through a modified mouth that affects the tidal regime.
“The river mouth has been extensively changed by dredging, to stabilise and nourish eroded banks along the foreshore of the Noosa Spit Recreational Reserve and to replenish coastal beaches. These intertidal sand banks are important foraging and breeding grounds for a wide diversity of commercially and recreationally important finfish.”
Further the professors speak about prawn behaviour:
“The abundance of food on the bottom affects [the prawns] distribution. Increased rainfall and riverine flows causes a seaward migration of these prawns with a temporary increase in abundance in coastal waters, followed by an increase in abundance in estuarine waters through enhanced recruitment, growth and survival of the post-larval stages.”
We all know that prawns move inshore and offshore dependent upon the balance of food, salinity, dissolved oxygen, temperature, etc. so it is important from a research perspective to do testing regularly in conditions that are as alike from year to year as possible to avoid distortion or skews.
Critically, the professors then say:
“It is not possible to distinguish among these (and any other explanations about prawn stocks) possible models for the decline in stocks without a comprehensive examination of the physical and biological conditions within the estuary.”
To simplify my perspective, surely the way forward with biodiversity should be (in no particular order):
- To construct and implement a scientific research regime/modelling for all fauna and flora in the river that will at least annually measure all important variables in a consistent and methodologically valid way over the long-term. One that highlights changes and possible causes;
- To comprehensively understand the impact the changed river mouth has truly had on the hydrology of the river i.e.flow rate, sediment, temperature, DO etc, and to create a monitoring regime that is consistent for the future – one that can identify causality.
- To understand the relationship that the changed river mouth has had upon fauna and flora in the river.
- To learn from other Australian states or authorities in a structured way as opposed to just from one source – best practice sharing!
- To manage all anchored vessels in the river and remove the obvious detriments i.e. vessels on swing anchors destroying the benthic layer and substrate.
Scientific food for thought…..
Another well written article Nick. You are spot on the money with your concerns about all of this. It is great that you can see how the holes have form in the science that can allow this to happen. You are very right in the testing regimes that should be worked as critical to our survival. As I view it all above science I really like hearing the scientific happenings around our country. Your information is extremely accurate and very relevant in this country.
Again I see a billboard with TCDD written on it.
During my studies of the Agent Orange spraying performed throughout Australia between 1959 – 1968 I found that the spraying occurred from just above Perth in the West right around the bottom half of Australia including Tasmania, where it all originated from, to just above Mackay in Northern Qld. The TCDD content from this spraying is exactly what caused the declines in this Marine life.
As you say there is a natural progression of stocks falling by rising human exposure but it is still not related to the damage TCDD can do. The TCDD oozing out of these areas that were sprayed with AO (245-T/24-D) for the next Four Centuries is the exact cause of declining stocks. I would be willing to bet that even though they have done all the work you mention they too have not tested for TCDD and have not identified the contaminated areas that are still causing the losses of Marine life. I can help anyone that wants the locations of all spraying of these chemicals throughout Australia by the Commonwealth Government and never reported to a single Government entity. I can help them to obtain the correct Government maps that show exactly where all of this contamination is if they so desire it. Could you please help these groups to realign to testing for TCDD which explains everything that science cant agree about. If they all formulate their data to the common cause none of them will disagree with what each other is saying. That is what has put the smoke screen in front of science in this country. Science is not working together to test every possible thing they can to see how to fix it and monitor the damage the TCDD is doing. Everyone was trying to come up with answers but none of them got to the cause. Even though all of the testing procedures you mention were thoroughly performed they also didn’t get to the bottom of what caused it which was the TCDD. If you could please Nick I would like you to relay my thoughts and feelings on this to the appropriate people concerned. I am happy to help them wherever I can.
Moving on back to Noosa. The River Mouth… What they have effectively done is destroy the deep flowing channel that flushed the Marine life back and forth and kept the river clean and replaced it with almost a cork on the whole river. There has been some serious blunders made with this river mouth in the past. The apparent reason for the shallower access and beach extension was to minimise extreme weather events on their newly created Noosa Sound. It is unknown if the Commonwealth Government ,that performed and approved the 245-T/24-D spraying in this river system played a part in stopping this flow of water reaching the oceans but it happened anyway. No-one apart from them was to know they were damming one of the most dangerous chemicals known to mankind into our ecosystem. The Commonwealth Government always knew of the AO spraying in the Noosa Shire but, despite all of my checking, never told any landowners or Government departments a thing and weren’t required to under Australian Law so there were no records kept. This change of flow rate through the river mouth has effectively contained the contamination to our wetlands and saved it from entering the ocean as much but what about us?
Possibly if the people that designed the whole new river mouth had known of the TCDD contamination they would of not changed it at all. Now that they have we have some severe problems to deal with.
The first problem we have is they have built a whole suburb of Noosa with TCDD contaminated materials. This will have to be either destroyed or decontaminated for safe human habitation. Like you point out Nick regular regimes of testing need to be put in place as soon as possible to produce and analyse the changing TCDD and other levels of contamination.
The next problem is this area where the river mouth used to be was also built AFTER the AO spraying occurred so is also contaminated. The Council have also made a Dog beach right in this contaminated landfill. That would mean that this whole reclaimed area needs to be dug up and decontaminated. Only the surface areas of this beach area would be decontaminated from the constant exposure to direct sunlight. Mother Nature has been good to us there and decontaminated all of our beaches for us.
But what about below the surface? As this is like an iceberg the levels of decontamination are only at the surface. Everything below the surface is just as strong or stronger than it was the day it first went there.
Then we have the flow problem…..We need to deepen the entire river mouth to speed up the flow of water to flush the TCDD out into the ocean where it will reduce in strength. The down side of that is the larger flow of water would also wash more TCDD into the furthest wetlands of the river such as Lake Cootharaba and Lake Weyba. As this is the only real way of decontaminating this river system specialist expertise will need to deal with these wetland effects. The Furthest areas should be made powerboat free and scientific study needs to be developed to try and construct some sort of filter that can extract the TCDD and set that up as the boundary limit for the boats. These filters would also filter out the extremely dangerous levels of TCDD realised during extreme rain events. Like you pointed out with your comments about the extreme rain event just before the problem suddenly got worse. That is the obvious leaching of the TCDD from the soils during the rain event getting into the waterways during the flood. That will keep happening. At this stage there is nothing we can do to stop it.
So a delicate balance needs to be worked out and then aimed at by science and the controlling powers. As it stands all of the construction work to reform the river mouth is contaminated material and needs to be completely undone. I hope that testing proves the TCDD has lowered it’s levels in the submerged areas of the river mouth but I know it hasn’t. There is a chance that the TCDD in the formed areas isn’t as bad as the river which also endured another forty or so years of it from the 24-D so let’s hope the AO didn’t do too much damage.
Effectively everything that was done by humans at the river mouth area will need to be completely destroyed again to effect decontamination. Mother Nature would of done her job and flushed the whole river system if it was left alone. Now that they have built suburbs from this TCDD laced landfill they have added Billions of dollars to the clean up not even thinking about what they spent to do all of the damage by building it in the first place.
Again science is asleep and hasn’t even had the slightest thought about what I am saying. When will the absolute pathetic science in this river stop? How much longer do we finance frauds like Michael Gloster and the TNC to make this contamination much worse? When will science catch up to what has to be done and start doing it. It is obvious from what you say Nick that the science throughout the entire country has gone into a coma with respect to spotting and treating TCDD contaminations. I can spot them from someone talking about it such as this story without ever doing a test. On those river systems will be a Pine Plantation in the catchment area somewhere. It is that obvious to me. A Commonwealth Advisory Board specifically for TCDD contamination needs to be set up as soon as possible to start telling all of the people about the areas they contaminated for Four Hundred years or more before I tell the whole of Australia what they have done. Oops.
I am glad that you have the expertise to check through all this testing Nick. You will find for yourself that the TCDD was never tested in any of the areas you mention. Because the Commonwealth Government did all the work none of the States are even aware of where these areas are. Because they aren’t aware of any spraying they don’t look at all for TCDD. We need to work together to get this information to the people concerned….