Mudflats on kanamaluka/Tamar Estuary have drawn the ire of many in the community for being unsightly, but for the flora and fauna the estuary supports, they are a sight for sore eyes.
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The nature of the estuary means that tidal flows change the amount of silt in the river, and the mudflats change as a result.
Prior to human intervention, this was a regular occurrence as well - such is the nature of an estuary system.
Dr Rebecca Kelly has devoted herself to the study of waterways and has worked at Sydney Harbour to explore how the system works in that region.
Dr Kelly is now the director at NRM - a company that consults on natural resource management and have conducted an independent report into the effects of raking on the estuary.
From Launceston to Low Head (and beyond)
In understanding the river Dr Kelly has recognised the importance of the system to sustaining a whole of estuary ecosystem that extends from the tiniest fingers of water tracking up into urban Launceston, to the residual effect of Tamar water creeping out into Bass Strait.
"The entire estuary is actually considered to be unique and really important from an ecological point of view," she said.
"The upper estuary [stretching from the waters of the North and South Esk rivers at Launceston out to Batman Bridge], which may be a surprise to a lot of people, is considered to be what we call an important bird area which is an international recognition of its importance. And it's now called a key biodiversity area, and that area extends all the way into Launceston."
Dr Kelly said the upper estuary was vitally important to migratory bird species and other threatened species which use the mudflats nearer to Launceston to exist.
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"It's a big tower and if you take one thing out the whole thing can fall over. We're a big piece of it and it has to be protected and that's why we sign up to all these international obligations," she said.
"But if you take one thing out, the whole thing sort of falls over."
Even in the very transcriptive and broad "whole thing", Dr Kelly's description is reserved.
The estuary does not just support one diverse ecosystem, it is home to a whole range of overlapping and interrelated groups that rely on one another for existence.
"[The migratory birds] actually use the mudflats for food. So they often eat the little animals that live within the mudflats," Dr Kelly said.
"And even the mudflats aren't just mud. They have a whole range of things that live within them - there are invertebrates like little mussels and snails that are in there - and those birds eat those things and some of them eat the fish that eat those things that live in the mudflats.
"There's a whole food web, or an ecosystem around [the mudflats]."
The reliance on just the mudflats alone is close to incomprehensible when one gazes out from Seaport or drives along Kings Bridge.
Dr Kelly said the intricacy of the ecosystem falls down as far as microscopic microbes that are never seen or heard, but are critical to life stretching along the length of the estuary.
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"There's little microbes that eat the stuff in the mud and then you've got little tiny animals that eat the microbes - it goes up this chain until at the top of that chain there are things like migratory bird species, and you've also got big predatory fish like sharks that eat the fish that depend on all of that ecosystem for their survival," Dr Kelly said.
"Ecosystems are this huge web of things that all rely on each other and at the very base of it is that habitat that has to be there."
In terms of ecosystems, the mudflats are just one part of the all-encompassing groups that rely on the estuary.
Next stop - The Tamar Wetlands
The Tamar Wetlands fall into the puzzle as well. Longtime wetlands volunteer John Duggin said over his time at the centre he had noticed how upper estuary changes, like raking, made an impact downstream.
"We've noticed that the level of sedimentation in the main ponds in and around the centre is much higher and we get a higher proportion of mudflats exposed on the low tides [when the raking happens]," he said.
"While they were raking and soon thereafter we certainly saw some changes. So in the last two or three years the levels have significantly changed."
Mr Duggin said the animals at the wetlands tended to adjust to the changes but what animals did appear changed.
"A lot of the ducks that require free water then have to move else where, but for those that have their food source in the sediment, it's probably a little bit better. So there are winners and losers," he said.
The Tamar Wetlands continue to support a similar variety of important wildlife.
Mr Duggin said the rarer animals continuing to use the biodiversity hotspot for refuge are the spotted crake, spotless crake, latham snipe, wading birds, chestnut teals, pademelons, quolls, southern brown bandicoots, copperhead and tiger snakes.
The wetlands has long been known to support the vulnerable Green and Gold Frog, but Mr Duggin said they had not seen or heard the frog for about three years.
How Tailrace Park has become a wildlife haven
What many may not know is that the foreshore south of Tailrace Park is another important facet that acts as a wildlife corridor and sustains endangered and threatened species.
"Nobody quite realises how important Tailrace is and how lucky they are," Dr Kelly said.
"That area between Kings Bridge down to the Tailrace, the first thing is that the swamp forest there, called Melaleuca Ericifolia which is actually a threatened vegetation community - at a state level that is protected.
"There are Eastern Barred Bandicoot in there and there are all sorts of really interesting things that just use that strip of vegetation along there for habitat."
Unwittingly, foreshore south of Tailrace Park has become a macro example of the balancing act between conservation and development. The park enables mammals and smaller birds to travel between Cataract Gorge and the bushland beyond, and the all-sustaining and important waterbody that is the Tamar.
Dr Kelly said connections like this were the lifeblood for balancing ecosystems.
"Things need to move in and out of areas, they need to be able to extend their range and every time you take out a piece in the middle and you fragment that habitat you make the things that live there much less resilient," she said.
"If you've got two completely isolated populations they may not survive."
The lower estuary
Further down, in the lower estuary from Clarence Point to Bass Strait, Dr Kelly said the breadth of that brick in the ecosystem building was only just beginning to be understood.
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"The lower estuary which has amazing values that we are really only just getting our head around what is even there at the moment," she said.
"It's a shark and ray nursery so it's known to be an area that's really important for breeding for sharks and rays.
"There are also these amazing colonies of sponge gardens and octocorals ... A few years ago there were something like eight totally unknown to science species found. Every time they look they find something really unique."
From Launceston and trickles of the North and South Esk rivers, to the vast Bass Strait, the Tamar estuary is an intricate web of life-sustaining ecosystems. And Dr Kelly said they are so closely interrelated and connected that a change to any part of them can reverberate far up or down stream.
"It's all really connected. When you've got an ecosystem you can never just take one piece out without reducing the resilience of the rest of it," she said.
"Eventually if you take enough bits out, the whole thing falls over."
Dr Kelly said finding the right balance between making changes to the Tamar and considering the viability of the ecosystems it supports was a delicate but calculated choice.
"Everything is a trade off. There are often trade-offs between the environment and people, but there are also trade-offs between people and people because it's so connected, you can't do one thing without it having an impact on someone else," she said.
"It's about how we make decisions so that we make the least impact, and the least sustained impact over time so that the ecosystem can survive at the same time we can progress.
"It's not about taking Launceston back to pristine vegetation, it's about where are we at now, and how can we make this the most resilient system that we can live in."
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