Crunch time for the Gippsland Lakes

Crunch time for the Gippsland Lakes

24 August 2008

Australia — Mollusc shells crunch beneath Ross Scott’s boots. He bends to scoop up lifeless handfuls, spreading them across his palm with an index finger to separate mussels and clams, pippies and barnacles.

Swept from the lake bed when there was nothing left to cling to, the shells form a 30-centimetre deep crust on Mr Scott’s neighbourhood beach. The mollusc deaths are just the latest in a series of deaths and disappearances that have blighted the Gippsland Lakes since the Thomson and Latrobe rivers flooded in June 2007.

With the floodwaters came the debris of the bushfires that burnt through the lakes’ mountain catchments the previous summer: a swollen slurry of ash and soil laden with the residue of tonnes of fire retardant, forestry pesticides, nutrients, heavy metals and chemicals accumulated from lowland farmland, towns and industrial hubs over a decade of drought.

With the Thomson surging into Lake Wellington in the west and the Latrobe into Victoria in the east, the delicate estuarian environment of Australia’s largest inland waterway was overwhelmed and, according to many, has never recovered.

For Mr Scott, a former state bureaucrat and river management consultant now considered a maverick by the Government because of his environmental activism, this is it: the ecological tipping point for Australia’s largest inland lake and wetlands system.

The Gippsland Lakes, he predicts, are heading towards the same strangled fate as the Coorong in South Australia; not enough clean fresh water, ever higher salinity levels, alien algal blooms and pollution that kills even the hardy barnacles.

But local independent MP Craig Ingram says fears that the Gippsland Lakes and wetlands are on the cusp of an ecological meltdown are unfounded and talk of such a crisis is undermining the region’s multimillion-dollar tourism industry.

“The lakes are not dead or dying,” Mr Ingram wrote in an appeal for calm published in his local newspaper last week.

“Many of these problems have been decades, if not a century, in the making and will take decades of concerted and sustained action to fix The negative publicity over last summer’s algal bloom turned potential visitors away and impacted on our region’s tourist industry.”

The cause of all the anxiety is an outbreak of blue-green algae that appeared last November and remains widespread across Lake Victoria, Lake King and Lakes Entrance, despite water authorities assuring locals it had come to an end in May.

Unlike the freshwater cyanobacterial blue-green algaes that bloom and die off every few years, the current outbreak of the marine algae Synechococcus has survived the cold winter months.

The algae turns clear water a murky brown and prevents light penetrating the surface, thus starving seagrasses and seaweeds that make up the core of the Gippsland Lakes’ food chain.

Environmentalists blame it for the disappearance of weed-feeding water birds and for massive mollusc kills.

It is 10 years since the CSIRO first warned that the Gippsland Lakes – a waterway stretching from Lake Wellington near Sale in the west, connecting via McLennans Strait to Lake Victoria, then Lake King near Bairnsdale and finally, through the man-made escape at Lakes Entrance, to the Bass Strait seas – were staring into an ecological abyss.

In the decade since, a forest of action plans have been signed off, taskforces and steering committees established, press releases issued and millions of dollars allocated by state and federal governments.

But identifying and redeeming the man-made threats amid an onslaught of unprecedented natural disasters has proved as difficult as navigating a dinghy from Seaspray to Lakes Entrance.

“The problem with the Gippsland Lakes is that it is everybody’s problem,” said Dr Graham Harris, the CSIRO’s former chief land and water manager who sounded the warning a decade ago.

“If you are staring at the algal bloom in Lake Victoria then you are standing with your back to the problem,” he told The Sunday Age. “It starts way back, up in the hills.”

Dr Harris added his weight to Craig Ingram’s call for calm, saying he did not believe the lower lakes of Victoria and King or Lakes Entrance were in danger of “tipping over” – as long as the flow of nutrients into the waterway was adequately controlled.

But Mr Scott and his supporters say there is no place for calm, that Lake Victoria and Lake King are in their death throes. “All the talk is of the Coorong (in the Lower Murray, South Australia) but the Gippsland Lakes are a witches’ brew of nutrients, pharmaceuticals, pesticides, fungicides and herbicides from agricultural run-off as well as heavy metals from industry,” Mr Scott said.

“Yet we have no ongoing comprehensive testing. Nobody really knows what’s in there.”

He crosses the sand and stares into the wind that whips up white caps on Lake Victoria. There is no protection on the south side of pretty Banksia Peninsula, even the tea trees seem to be retreating from the water.

Mr Scott believes nothing is safe there any more. He no longer swims to the opposite shore of Duck Arm, the inlet he has spent 48 years observing. He would never dream of letting his grandchildren splash where his children once played.

The waters around his jetty are a stained soup of brown marine algae that under normal circumstances would not survive in the brackish lakes. The algae is preventing sunlight from reaching the water plants below and denying them the opportunity to photosynthesise.

Barnacles coated the jetty’s pylons before the floods swept through and the sea grasses and reeds began to die.

“What was in that water?” he ponders as he recites the timeline of disappearances from his neighbourhood.

“All the sandworms and crabs are dead; and so is the fishing bait industry,” he says.

“There appears to be no seaweed and the only surviving bed-stabilising sea grass appears to be in patches where some light is getting through. This is the first time a Synechococcus algal bloom has been in the lakes and it is destroying the food chain for weed-eating birds.

“Starving swans started grazing on lucerne paddocks, so they were shot under DSE licence.

“Now most of the water birds have left; swans, ducks, coots, cormorants.”

Water rats have also disappeared.

Six years ago the State Government established the Gippsland Lakes Taskforce in response to Dr Harris’ original report. The taskforce chairman, Chris Barry, concedes the lakes are under stress but disputes Mr Scott’s prognosis.

“We have come off the effects of historical low rainfall, one-third of the catchment burnt in 2006-07 and an extreme flood event,” Mr Barry said. “We think Lake Wellington has tipped over but I am not in a position to say whether Victoria or King are at risk of tipping. There is no real precedent.

“We won’t really know about the seagrass beds until late spring or early summer. We are seeing spider crab and shrimp again. We are expecting (the algal bloom) to disappear in the very near future.”

But Mr Scott is less optimistic. He believes contaminants entering the system upstream have done irreparable damage.

The State Government management plan, developed in conjunction with the East and West Gippsland catchment management authorities, is focusing on addressing the problem of upland nutrients being washed into estuaries.

But critics say the Government must implement comprehensive water-quality testing that monitors pesticides, pharmaceuticals, hormones and heavy metals.

A recently published independent study of pharmaceutical run-off levels in the waterway found a network of farm drains and watercourses carrying veterinary pharmaceuticals into the estuaries in untreated effluent from the dung of 100,000 cows: the equivalent of sewage produced by a city of 1.5 million people.

“It’s easy to finger nutrients for all the woes,” said research scientist Dr Peter Fisher.

“These flows not only carry nutrients but also antibiotics and it would appear, synthetic and natural hormones and pesticides which, in turn, may have interacted to form complex chemical mixtures.”

He said regulations were needed to cover the use of such drugs, because they were capable of producing resistant wild bacteria.

But Australia is not testing water catchments for hormones, antibiotics, pesticides, insecticides or fungicides. “Not only are we not testing for these products, there are no laboratories available capable of doing this range of testing,” said Mr Scott, who co-wrote the report.

24. November 2017/by GFMCadmin