After The Flood Comes The Kill
It was unlikely the Wilsons and Richmond Rivers would exceed their record flood heights so soon after the 2017 event. And it was highly improbable they'd both flood again just one month later. Yet that's exactly what has happened.
As the waters rose yet again, Steve Shearer researched and wrote about post-flood fish kills, a little-understood phenomenon, though if recent patterns continue it's one we'll be seeing much more of.
The debris is still piled up high at Lismore after the Februay flood, overtaking '74's famous deluge to be the largest in recorded history.
The flood's destructive power has amassed another mass casualty with a fish kill being evident through the lower half of the river system. Another mass kill has also been reported from the Clarence River, one basin south.
These mass kills are devastating to coastal and river communities, wiping out local ecosystems and annihilating recreational and commercial fishing for significant periods of time. For surfers, they contribute to the general toxicity and no-go zones of the rivermouth and near rivermouth breaks as sharks scavenge up the dead fish.
The causes? There's a few factors involved but the primary cause of fish kills after floods is a lack of dissolved oxygen in the water. Like humans, fish and other marine organism need oxygen. Without sufficient dissolved O2, they suffocate. Deoxygenated floodwater is commonly called 'blackwater'.
What causes the blackwater? A few things. Bear with me, this gets a little complicated.
(ABC North Coast)
When a river breaks its banks during a flood, vast areas of land go under water. These areas are what is known as the floodplain. In the local case of the Richmond River it has the largest floodplain for the size of the catchment of any river in Australia. It's a vast area.
Before European habitation and the advent of agriculture, the floodplain consisted of many low-lying swamps which were perfectly adapted to being inundated by floodwaters for long periods of time. These areas, like Bungawalbyn Swamp and Tuckean Swamp in the Richmond, and Everlasting Swamp, Shark Creek and Coldstream wetlands in the Clarence were incredibly productive fish habitat. The vast majority of these swampy, low-lying areas have now been drained and floodgated and converted to agriculture.
The flood-adapted vegetation has been replaced by pasture grasses and other plants which are intolerant of inundation yet grow on the drained wetlands. Floods, especially summer floods, which inundate the floodplain cause the death and decomposition of huge areas of pasture grasses. Bacteria and sunlight do the decomposing and in the process the water is stripped of all oxygen. Compounding the problem are acid sulphate soils (ASS) which create an acidic environment that can sometimes be as low pH as battery acid.
This hypoxic blackwater then drains off the floodplain through floodgates at high rates, after the flood peak. The drains also build up a substance known as Mono-Sulphidic Black Ooze (MBO), which is about as charming and toxic as it sounds. MBO describes the black, organic gel-like sludges that form on the base of drains in ASS areas and contain high concentrations of monosulfides, a chemical compound of iron and sulfur.
(Steve Shearer)
You won't be surprised to hear fish and millions of other marine organisms don't stand a chance as the river becomes saturated with the stuff.
So why don't the fish swim away, you ask?
They do.
Some escape. However, a lot get caught sheltering in lower reaches of the estuary in cleaner, more saline ocean water which is denser and creates sanctuaries in the deeper holes. Blackwater can go over the top of these fish on an outgoing tide and then flood them in on an incoming tide, essentially trapping them in as they seek shelter from the deadly slugs of blackwater.
Tens of thousands of fish have died from this event. Hundreds of thousands died in huge fish kills in 2001 and 2008, which was the “biggest ever seen in Australia” according to expert and CEO of Ozfish Craig Copeland.
The effects are devastating, not only to local industries but to the psychology of those who depend on and love the river. Ballina-based marine veterinarian Dr Matt Landos, said he felt “numb with anxiety” at the scale of the recent fish kill. Landos described the system of floodplain mismanagement as “grinding the ecosystem to a pulp”.
(Steve Shearer)
It's an issue dear to my heart. I've got skin in the game: the river has supplied fish for my family and I for decades. The degraded water quality affects me and everyone else who surfs in the area.
Recently, while walking along the beach at North Wall I became overwhelmed by the stench of rotting fish on the beach, including three monster mulloway (jewfish). I felt a blank feeling of despair. Local writer Peter Bowes described the scene:
"The Richmond River is poisoned with rank freshwater, drums of fertiliser, spilt diesel, sewerage, mud and town runoff…the waves are breaking in rancid water, the beaches littered with timber and dead fish, a trio of jewfish the size of an overweight man, slowly deflating, their distended stomachs almost ready to burst.
Silver bream, mullet, catfish, small sharks, tailor, flathead, trevally, blackfish, toadfish all white and ballooning and covered with spikes looking like something you could hang off a Christmas tree.
Everything stinks.
Seagulls too used to fresh fish to bother picking apart the days-old carcasses; sand crabs almost too wary to spot as they disappear into their holes holding gobbets of decomposed fish in their claws and further down the beach a walking platoon of black crows comes your way. Slowly. Stopping and stooping here and there before walking closer, unafraid, sleek, well-fed, confident.
They only take the eyeballs. And there’s hundreds of dead fish without them today.
Like oysters, Sightless. Liquid. Viscous. Putrid.
The Northern Rivers rejoices in a clean and green image, which it retails to the world. The disparity between the perception and the reality is obscene during these mass ecosystem collapses. Marine parks are the conservation movements fashion du jour. The local streets are full of tattooed tech bros in Teslas, festooned with green stickers to show they are 'doing their bit'. Meanwhile, the deeply unsexy backswamps and floodplains off Broadway sit and fester, ready to unleash a death-dealing toxic load which can wipe out an entire river.
What is to be done? What can be done?
Southern Cross University geoscience professor Scott Johnston said a big-picture solution was needed to fix the problem. He said estuaries were overwhelmed by the frequency of stormwater events due to human interference in floodplain drainage.
Professor Johnston said thought needed to be given to the types of vegetation being grown in important drainage areas.
"There may be some areas where the wetlands are better functioning as wetlands," he said. "To do that requires long term co-ordinated management, and also a big conversation that involves the entire community."
The Richmond River is cooked. We can all see that. Fixing it will take money, political will, and hard action. Not only is it becoming incapable of supporting its current human habitations but its entire ecology is in need of serious repair.
In the words of OzFish CEO Craig Copeland, “We have to do more.”
In the meantime, the rain keeps falling and the rivers rise again.
// STEVE SHEARER
Comments
Thanks Steve, I saw this same man made problem happen on a smaller scale in Killick Creek, Crescent Head many years ago. As kids, my family could survive for weeks on whiting, flathead and crabs from the creek (topped up with greens and bakery goodness), and then one day, the flood mitigation scheme was put into action.
Soon after, following a good soaking, the crabs took to the sand to get out of the water and the fish just died or left.
Still the same today.
"Take paradise and stuff it with bad planning"
Heart breaking but thanks for the informative and detailed. Hopefully independents like Hanabeth Luke, with integrity and qualifications, get elected in Page and usher in real change.
Lots of leather jackets from the flooding down here. Eyes gone. Also this rat/pig?
And all the jellyfish from the Hawkesbury and maybe inside the harbour have been flushed out and are swarming the lineups. Big fleshy blob ones.
I worked for many years in the early 2000's in the Blackwood River Estaury (WA) studying the impacts of restocking Black Bream into a depleted estuary. If you went back through the catch records it became apparent that the depletion of this species could be heavily linked back to the record flood events back in about '74 as I recall, and they had never really recovered since (although other environmental and human factors were also at play). Our restocking efforts helped increase numbers of Black Bream in this estuary over the mid-term as many restocked fish were able to reach maturity and have continued to help increase numbers and impact the river ecology since. It just goes to show that record flood events like the current one where you are Steve can have very long lasting impacts.
Large scale "eco-engineering" efforts starting high up in the catchment as described/practiced by the likes of Craig Sponholtz, Darren Doherty and other systems based practitioners (who have had a hard time making their thoughts and efforts recognised) seem to be at least a large part of the answer....as well as slowing and attempting to reverse/mitigate the trends of, and associated, with climate change. Slowing down water flow and helping infiltration into the landscape from as high up as possible is the go and benefits land and water based ecosystems in so many ways, including in times of drought.
Its funny (or sad) that the solutions we are looking for are all well documented and at least partially validated by movements such as Project Drawdown (https://drawdown.org/) which has numerous action plans and resources that most of us could lean on and help implement or bring greater awareness to. Its so frustrating. How you get this stuff taken seriously at scale seems to require these types of disasters unfortunately.
Thanks again for calling out and dissecting in an engaging way something that needs all of our attention. Hope it stops raining in such a devastating fashion up your way soon.
Well written and knowledgeable article Stanfrance.
In regards to the Restocking that you guys did in the Blackwood I would have to say its been a real success.
The experienced fisherman will have good catches of Black Bream 30 : 40 cm +
and the less experienced will have non stop toddlers and just undersize.
From what I understand that is the sign of a healthy Estuary system with fish of all sizes being caught consistently.
I have been fishing in there for the last 25 years and seems to be better every year.
Maybe the same type of model could be implemented into the water ways of concern over East, best wishes to all effected by the floods.
Thanks for that feedback Blakey. I haven't been back there for quite some time so that's really interesting that you believe the fishing is improving. We released fish (220 000 fingerlings) back in 2002 so the 30-40cm fish would definitely be in that cohort. You can tell if it was a cultured fish or not by looking at the otoliths. If they have a purple stain visible near the core it would one of ours (we swam them in dye to stain the era bone before release so we could easily track them).
Restocking is definitely a lot more common these days with and there are some really interesting trials taking place in areas such as the Clarence River Estuary where they are measuring and valuing the contribution of ecosystem restoration techniques on fisheries, habitat, water quality etc and using those to validate this approach for expansion. The guys taking this up will be corporates, governments and industry looking to invest in natural capital to secure resources, reduce risks associated with collapse in production and of course to look much better in the public eye (aka invest in building social licence).
So its interesting times. As long as it happens quickly enough, now that formal trading schemes are being ratified to trade in natural capital (see ACCU's, blue carbon etc), there should be a massive pooring in of investment in rebuilding ecosystems and the natural processes they rely on. One would think that would only make good sense.
Nice one Steve, well researched.
Devastating stuff. Thanks for shedding light on this.
It is a yearly occurrence in Far Northern Australia (WA, NT, FNQ) during the buildup/early wet season. But I believe the major difference is the lack of population and human disruption in those large areas, leaving it as near to it's natural state, compared to what is being experienced further south at the moment.
Devastating sight and effect regardless.
Going into the ocean to "cleans thy self" seems to be off the cards again for a while.
Thanks for shedding more light on humanities follies.
onya steve
That's a very informative but despairing read as you know the same will be happening to river systems all over the planet (at least where humans congregate and live).
Thanks for taking the time to put that together S.S.
Steve, you may have already found this document, but if not it’s a good summary.
Competing land uses on the floodplains are difficult to resolve.
https://www.environment.nsw.gov.au/-/media/OEH/Corporate-Site/Documents/...
Haven't read that one Distracted, but several similar ones, particularly about the Richmond floodplain.
Cattle are worth more than fish, is about the size of it.
The planet would stand a more fighting chance if we didn't value cattle so much.
I reckon it’s slowly heading that way, if nothing less because of the cost. Steak at the pub the other day was over $40 ummm… I think I’ll get the chicken.
$3200 per head for a heifer this week at the recent sales up your way im pretty sure i heard on the midday report. can't afford a fence though unless its a token bit of wire on top of the bank.
excellent article for all
It's heat breaking seeing major fish kills like these. Great write up.
But yeah, it will be hard to turn around after nearly 200 years of European settlement (land clearing for timber then farming), recent decades of poor flood management (drains/levees etc) and a lack of support from various land owners and stakeholders (complicated by lack of incentive from the Gov.) .
A clip from the Rous City Council on the current flood management in the area. (Sept. 2021)
Agree with all the above.
Although Rous County Council is a joke of an organization
why?
5 minutes in I can't watch any more, don't want to hear any more. Just down right bloody depressing this obvious bastardisation of this land.
I am of Dutch heritage. Thought I would be ok with water diversion, mitigation or whatever for agricultural purposes.
Mining sand dunes etc I had not heard of many such greedy early practices before swellnet. Such interesting contributions I greatly appreciate crew.
Mother nature, Steve and contributors you have hit a nerve in this household.
I hope I can contribute towards some positive environmental turn arounds in days to come. Otherwise I will continue as normal on the band(aid) wagon.
And still they clear.
progress is priceless they said. 1959- 2022 = 62yrs Just over half a century. People where talking about it then as they are now.
Good work Steve, thanks for bringing more light to a dark story with few voices. Keep powering.
You should talk to some indigenous elders, Steve. It would be good to hear what they know.
Good luck with that.
If I was an Indigenous Elder I wouldn't give a white C#@t the time of day, let alone a shred of advice or skerrick of sacred knowledge.
https://www.edo.org.au/publication/native-vegetation-clearing-laws-in-qu...
it's shameful we let these god bothering conservative w@nkers cripple the CSIRO for years, we desperately need a science based approach to land management.
We have the science and know how. The will. Government should encourage better management and close the loop holes to steer it in a much needed healthier direction. By not taking a harder line they are allowing the continuation of a preventable outcome of poor practice. Harder refinement is needed in actual deliverance of a better outcome that is all ready known through past knowledge and action.
Yeah. If u believe in an end to the world/ apocalypse/ second coming then you wont give a f$k about exploiting the fruits of the earth. But dont they know you can't take it with u? I don't get it...
yeah Abbot/Turnbull/Slomo all played their part to the dismay of the global scientific community.
http://www.australasianscience.com.au/article/issue-janfeb-2016/open-let...
Revelation 11:18 "God will destroy those who destroy the earth" when He returns. No Christian would be caught dead 'destroying the earth' wholesale like many actively do, rather the Good Book encourages care and appreciation for the natural environment, love your neighbour (do what is best for everyone, not just your bank account) and don't harm anyone who does not believe the same as you do.
https://www.abc.net.au/news/2022-03-31/floods-lismore-byron-bay-northern...
"Between 1887 and 1893, the town experienced three major floods, ranging between 10.43 and 12.46 metres.
Between 1962 and 1965, the town endured three more floods over 10 metres.
And in 1967, Lismore flooded five times between March and June, with floods ranging from 5.09 to 10.27 metres."
Super knowledgeable article. Cheers FR.
To think the floodplains were transformed so drastically, the sand dunes had the vegetation stripped for mining. Entire estates built on swamplands. Freeways cutting through key habitats for Koalas and other vulnerable species. Homes built on the edge of sanddunes. Agricultural topsoil full of toxic substances.
Now it's becoming clear why nature designed herself the way she did, and how easily she'll reassert herself, to our own detriment.
Also just read StanFrance's great input above. I didn't realise WA had a huge flood in 1974 as well as the one on the East coast. That's phenomenal.
G'day Blue Diamond. You can read about the massive flushes in the Blackwood River and changes to the estuary ecology if you search up Rod Lenanton's paper published I think in 1977 or Fiona Valesini's writing about fish ecology of various WA estuaries published in 1997. Reference to those in our project reports published 2004 for the FRDC.....pretty dry reading though :)
Unreal! Thanks Stanfrance! will check it out.
And yes....i see what you did there!! haha. Classic! ;-)
Excellent work Steve.
This tragic ecological story & its causes were known, however the facts may be filtered the mainstream media ....atm.
Most commercial media is reliant on marketing, managed by the rich multinational businesses to persuade people (via carefully crafted images & sounds) using our primal desires, needs, dreams .... to create constant craving & sales. Governments are elected by people (over 18) in Australia atm; caught up in this current society's mainstream media atmosphere.
eg. " Sugar....natural part of life" $20M add campaign https://researchonline.jcu.edu.au/344/
The earth will re-balance itself, however we humans may become meek nomads.... if history & commercials repeat.
What was this great desert land called by the British lords before they claimed it. for England?... "Terra nullius"
Latin for "Nobody's Land"
https://en.wikipedia.org/wiki/Terra_nullius#Australia
When are these medieval practices going to turn around to be planet, human, species friendly for the long game.
Are the powers that be just thinking... rape, pillage, squander until that asteroid hits or that massive volcano chokes but a few to continue back to basics existence?
Thanks for the Gong, Steve, and one old boy reckoned those big babies might have been river cod.
There was a QLD groper washed up on the spit behind the skatepark.
The environment re biodiversity, habitat, pollution barely rates a mention, it's an indictment on where societies at. In fact our local member nearly brought the NSW coalition down to stop koala habitat protection and this on the back of bushfires of the same magnitude as our current floods, which also swept through these vital wetlands-fuck knows what cumulative impact on top of the drought this will have.
We've got feral pigs foraging some of our quieter beaches most likely forced out of flooded wetlands, creating almost apocalyptic scenes of flood debris including fish and cattle carcasses, massive erosion of foredune vegetation strewn everywhere all being lapped by putrid brown seawash. This shit is real.
Thanks for this article. Very important for all to know
Maybe the world just needs another season of Ultimate Surfer.....(humans....sigh)
Well written. The more that can be done to shine a light on the the cause and impact of these floods, the better. In particular the mismanagement of flood plains.
These problems aren't going away but to address them there needs to be a wholesale buy in from Joe public. The dichotomy between how many residents of flood hit areas view their surroundings and the reality is stark, walking around repeating the 'another day in paradise' mantra is if that will make it so only serves to enable the planners and shire councils who are still clearing land and building on flood plains.
Communities need to be asking more questions, not just about when things can return to normal. At this stage I can't see it happening, people are still surprised these floods happened at all.
It'll never happen, upnorth.
Check out Brisbane and some aspects of the North NSW Coast. Dial Google earth right out. It looks like the Amazon delta.
People round here call me Noah or a mad bastard, which, in part, is true (the mad bit).
On the Sunny Coast all the good land was long gone by the late 70's early 80's. Since then it's been gratuitous land clearing, wanton development, and - what irks me most - the decimation of wetland, natural creek and mangrove ecosystems, replaced with canals, stagnant lake waterfront, concrete, colorbond, and brick veneer.
When the cat 4-5 cyclone crosses, or a "rain bomb" goes off, like the one that unleashed on NNSW - and it will - the place is gone.
Blame game: Government, council, developers, builders, real estate agents, investors, buyers - we are all complicit in flooding the coast with inferior product in parts that should never be developed.
A myopic 360 deg view.
Karma, man.
I look at life like this - Live in the moment because none of us are getting out alive anyway. Don't be too attached to material things, pets, people, or one's station, because any or all of it can be taken away at any moment.
Why is no one talking about the blatant weather manipulation and constant chemtrail spraying? They create the problem, fuel the reaction and provide the agenda's solution. If you need proof just look up.
"If you need proof just look up."
And thus, another conspiracy theorist sets into motion a long, exhausting journey for the layperson to find "proof" of the whatever it is that they're claiming is the cause of an event that's otherwise adequately justified by science.
It's the ideal business model: put the onus on everyone else.
Just look up at the sky Ben, not look it up yourself. Bit trigger happy on being offended mate.
Nah, not trigger happy, just sick of the endless bullshit conspiracy theories that seen to pop up everytime something happens.
Well let's focus on facts then. Read things properly before you jump to conclusions from now on.
Your claiming "blatant weather manipulation and constant chemtrail spraying" as facts?
Might as well end the conversation here mate.
This is going nowhere Ben. The only fact I am claiming is you don't read things properly. I think we both have better things to do with our time. Thanks for the interaction.
A couple of things on this having had a long history working for research, advisory and management agencies for coastal matters.
1. This article says from the outset "It was unlikely the Wilsons and Richmond Rivers would exceed their record flood heights so soon after the 2017 event." Sorry, but this is a completely misleading statement about flooding.
Floods are complex events and are classified on their probability - this has historically been based on years, for example the classic 1 in a 100 year flood ie a flood like this will occur in one year out of every hundred years. This expression of flooding probability has been replaced these days with the far more straight-forward concept of Annual Exceedance Probability (AEP), where a 1:100 flood is now called a 1% AEP flood. This is a much better reflection of the intent of the 'yearly' idea - it means there's a 1% chance that a flood of that magnitude will occur in the year. Unfortunately, the yearly approach is easy to misrepresent by the likes of Barnaby Joyce, who demonstrates he has absolutely no idea about floods, and promotes a very inaccurate appreciation for the concept of probability and real-life flooding.
The yearly concept misleads people into thinking that it only happens every so often, while the whole gamble actually resets every year and previous events, records and whatever ease are pretty much irrelevant. Hence this opening statement plays straight into the old-school way of thinking, which is the precise way of thinking which has gotten us into this utter mess of how to approach the twin challenges of climate and flooding. It's truly yesterday's thinking.
A 1:100 year event has the same chance of happening next year as it did this year: 1%. A 1:1000 year event is the same - each year it has a 0.1% chance of happening. Whether it happened last year or 100 years ago makes NO difference. Hopefully people can now see that with La Nina x climate change all bets are off.
2. It's so dispiriting that the Richmond is still so screwed up when the information about the key issues in the Richmond (and most other coastal river systems around he country) has been settled for decades. I was involved in all this stuff over 20 years ago with a good many good people including Craig Copeland, and it makes me despondent that the impacts are still occurring. It's a disgrace that successive governments haven't been able to improve things in a meaningful way when so much effort and funds have been poured into it all.
Excellent point Tango!
The 1% chance, every single year is certainy more meaningful and useful than the '1 in 100yrs' metric when weighing up risk. Many years ago I rolled the dice on a Tweed Heads foodplain property, incorrecty assuming that after a recent food the risk of another was essentialy 0 in my remaining lifetime. luckily I found a more desirabe property and got out after a few years. That property and many around it have gone under 3 times now in the 25+ years since.
You also wrote: "It's a disgrace that successive governments haven't been able to improve things in a meaningful way when so much effort and funds have been poured into it all."
You can insert pretty much any problem and sebsequent govt program into that statement. Other than rapaciously fleecing us, what do they do well?
Sadly, one thing I have never gotten wrong is my distrust and cynicism of polititions or govt.
https://m.
I suppose that's the problem with Westminster models of government - full of generally good and capable public servants but controlled by politicians (and media) and their acolytes.
My point was meant to be more along the lines of the problems are still problems despite the effort that's been invested by the pubic sector, private sector and researchers to develop solutions. In many cases there are quite realistic solutions that have been created and could be implemented, but of course the polity always trumps the policy.
I watched a set of fifteen foot mud brown barrelling rights breaking half a mile off North Wall this afternoon, all unworried by the trails of distant boardriders, glistening strangely in the afternoon sun, too heavy with silt to blow out a spume as their concaves collapsed to then wash up on the beach almost spent only to disturb the opalescent scrimmage of thousands of black carrion flies feasting on the carcass of a drowned calf.
Great informative read Steve - thx.
We'll keep hammering the environment until it starts to unravel completely. We need the planet, but the planet don't need us.
This is so disheartening for us waterfolk.
I have read that oysters can filter bad water and help to keep it oxygenated.....very much like the mangrove trees do.
I wonder if these may help against the deadly blackwater?
"what irks me most - the decimation of wetland, natural creek and mangrove ecosystems, replaced with canals, stagnant lake waterfront, concrete, colorbond, and brick veneer.
When the cat 4-5 cyclone crosses, or a "rain bomb" goes off, like the one that unleashed on NNSW - and it will - the place is gone."
Pretty much sums it up Damo-b. But then we have been indoctrinated to believe that these semi permanent colorbond settlements are paradise, that we live in the best country on earth and that to say otherwise is un patriotic and undermines what it means to be Australian.
Is it any surprise that in the face of the effects of environmental destruction such as the recent floods, the clamor for change is so lacking. We have form, there weren't many complaints as we slowly drained the Murray Darling. Extracting water from such a massive river system to the extent that barely a trickle reaches the river mouth takes some doing.
While people aren't immediately effected by environmental mismanagement there is a willingness to turn a blind and eye, a bit of 'I'm alright Jack' - its another state, another city, town . . We've been taught to cherish our little corner of paradise above all else which is why when the writing is on the wall we can't see it and when settlements are swept, blown or burnt away, it comes as such a shock.
tbh
the people that bought house in lismore aren't to blame
the sugar famermers downstream have fields arent to blame
this drought in chile is the problem
4 million litres a day of Raw sewerage released into Wilsons River - Per farkn Day !
https://www.abc.net.au/news/2022-04-08/byron-bay-beaches-fouled-by-filth...
Grat article and thanks to Swellnet for covering such topics. Such a disgraceful way we have farmed this country and still do, by and large. Has your superannuation fund invested in the big farms they and the banks now own?? We are all guilty in some measure. Eating fish is a luxury we can no longer afford. Stop catching / eating them for a year and let the poor buggers recover.
Local Marine Biologist who spends a lot of time assessing the inter-tidal rock pools and inshore lagoons has a sobering assessment of the impact on marine life after the degraded water quality related to the flood.
"I am back after a very long absence, but I am afraid I feel very glum - just like the crab in this image looks. I have finally gone back jn the water.
I knew there was a good change of high mortality, particularly of sessile invertebrates in our bay after 1/4 year of foul water quality, but nothing prepared me for such a loss in biodiversity. Many groups of benthic fish absent, no featherworms, no seastars, no bryozoans, no featherstars, sponges, ascidians, non- zooxanthellate anemones all gone, no nudibranchs, no flatworms, very few crabs and not a single octopus.
Devastating.
It would be completely un- scientific to extrapolate from this one site to any larger ecosystem impacts, but if you have- like me- have observed individual worms, ascidians or sponges over a decade you would feel raw too.
Of course - there maybe a swift recovery next spring, but given that almost all the groups I refer to are broadcast spawners, our bay relies on a good larval influx from (mainly) up North, an area which has badly been affected too. So the proof will be in the pudding… and hopefully this little blog will be one of stories or resilience & recovery."
It’ll be fine. Give it time.
There’s doom mongers like this after every natural event. Remember when we were told that the bush would never recover from the 2019 fires because they burnt too hot? How’s that going ? Hint: Very green and healthy.
Or the marine biologists I met at Waroora station a couple of decades ago who told me that coral bleaching had destroyed the Ningaloo reef forever….lololol.
Wouldn’t be in a hurry to eat the pippies around your way though. Probably alright by now I guess.
Sure, things recover.
I still haven't put a tailor in the fridge since the start of the year so I hope it does.
It's still a sobering reminder of the damage from these floods.
It's more the loss of fauna that has been the ongoing issue.
I'm not aware of any counts done recently but on my multiple times into the Blue Mountains the lack of lizards, snakes, and form of marsupial is worrying.
Down the South Coast it's good to see lots of wallabies and kangaroos bouncing back.
Some of the regrowth is crazy with all this rain. Need a machete on tracks that were easily accessible.
re the fires - I believe there are some areas that have not and likely will not recover to what they were. It is ecosystem change from forest to something different - shrubland/grassland. Due to repeated intense fires before the regrowth has a chance to get to the age were it can reseed the area. This is documented elsewhere too - e.g. North America
Agree, it appears some areas that did burn super hot haven't recovered as quickly or to anywhere near the extent that other regions have. Still black and mostly bare.
thanks for confirming Craig. I'd wondered if you'd encountered such areas in your travels, going by some of those epic photos you've posted.
time will tell what those changed veg communities will do in the long-term, maybe transition back? For me, as a forester, it is particularly interesting seeing so-called 'climax' communities change in quick time. The 'climax' community is conditioned by climatic and edaphic (soil) conditions. The climatic is typically most strongly influenced by rainfall, but we are increasingly seeing the combo effect of drought and fire (and mass insect kills in the case of Nth America) lead to rapid community change.
I wonder if kelp forests will also change
GreenJam
See these stories for impacts to Tassie kelp
https://www.abc.net.au/news/science/2021-02-27/tasmania-giant-kelp-fores...
https://www.abc.net.au/news/2021-10-13/kelp-forests-off-tasmania-regrowi...
thanks lomah.
Great to see some success with the restoration work, hope that continues.