RE-BUILDING A REEF

Threats to the survival of the Great Barrier Reef have been well publicised. Lesser known is the state of the shellfish reefs of Victoria and South Australia where up to 99% have been destroyed because of a long history of dredge fishing.

A group of scientists, fishers and conservationists is working to restore one of these ecosystems in Victoria’s Port Phillip Bay using mollusc shells recycled from restaurants.

For two years the Albert Park Yachting and Angling Club and The Nature Conservancy, in collaboration with the Victorian Fisheries Authority, have been collecting oyster, mussel and scallop shells from Geelong restaurant and seafood suppliers. 

They have so far collected more than 420 cubic metres of shells which otherwise would have ended up in landfill.

Initially the shells were stockpiled and left to cure for six months of exposure to the sun and wind so that any diseases they might have been carrying were killed off.

In November the group began spreading shells and limestone rubble on the sea floor at two sites to form bases for reefs for Angasi oysters (Ostrea angasi).  This month the group will work on building a reef base for blue mussels (Mytilis edulis).

These new reefs are being placed where suitable reef habitats have been depleted.

It is hoped that their establishment during the natural oyster and mussel spawning season will lead to remnant populations colonising these reefs.

However they are not relying solely on natural recruitment.  More than 10 tonnes of live blue mussels supplied by aquaculture farmers and about 350,000 oyster spat from the Victorian Shellfish Hatchery are being introduced to the respective sites.

Simon Branigan, The Nature Conservation’s marine restoration coordinator, expects that after about three years the shellfish reefs will stabilise and start to grow.

As well as increasing the bay’s shellfish population, the project is expected to benefit other species providing habitat for a variety of marine life and improving water quality as the shellfish remove excess nitrogen and inorganic materials through filtration.

Similar projects are planned for South Australia and Western Australia.

- Leonie Blain

 This article was originally published in the VOICES FOR THE EARTH column in The Daily Examiner on March 19, 2018.  

For more information on the commencement of this project, see The Nature Conservancy's Vistoria's biggest ever reef restoration project hits the water.

POSITIVES IN THE CLIMATE BATTLE - BACKYARD SWIMMING POOLS AND ENERGY USE & THE CLIMATE COUNCIL'S RENEWABLE ENERGY ASSESSMENT

Here's more good news on the climate change battle front. Last month, Fairfax Media reported on a multi-million dollar project predicted to massively reduce electricity usage during peak demand periods.

The scheme is focused on a somewhat unlikely target - backyard swimming pools. However, I was surprised to learn there are more than 1.4 million swimming pools in Australia accounting for an astonishing 10% of the average total demand on the electricity grid, and if all pool filters were running together, it would require the equivalent of two Liddell-sized power stations running at full capacity.

Clearly there is huge scope for savings, and the trial by Pooled Energy, which is supported by the Australian Renewable Energy Agency, would involve about 5000 homes and see householders hand over control of their backyard pools to return power to the grid during periods of peak demand.

According to the company's co-founder this can operate like a battery, reducing or increasing load as needed by providing demand management using an off-site smart network that collectively controls power usage of separate pools, making a major impact on energy load.

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At the same time the Climate Council, famously de-funded by former Prime Minister Abbott in his war on all climate change related matters, has remained active, and recently released a positive report on progress towards the transition to renewable energy.

The key findings of their report, which focuses on battery storage include:

- The cost of lithium-ion batteries down by 80% since 2010, with costs expected to halve again by 2025.

- 6,750 new household batteries installed in 2016, with estimates that 20,000 were installed in 2017.

- Renewables now provide 16% of Australia’s electricity.

- Victoria, Queensland and the Northern Territory are also investing in grid scale battery storage technology.

- Federal, Queensland and Tasmanian governments are considering developing pumped hydro projects.

- Australia could reach 50% renewables by 2030 without significant new energy storage.

- Australia must reach zero carbon pollution well before 2050 to effectively tackle climate change.

More cause for quiet optimism.

 -John Edwards

 This article was originally published in the VOICES FOR THE EARTH column in The Daily Examiner on March 12, 2018. 

GAS MINING IN THE NORTHERN TERRITORY

Governments around Australia are under pressure to allow development of coal seam gas and shale gas reserves.  The pressure is from the gas industry and associated industries which will profit from gas mining - as well as the Federal Government. 

The Federal Government is pushing the expansion of the on-shore gas industry in NSW, Victoria, the Northern Territory and elsewhere because it claims this is necessary to ensure cheaper gas is available for Australian households, manufacturing industries and electricity generation. 

 

Currently there is more than enough on-shore gas being produced for domestic purposes but it is all being exported due to the failure of successive federal and state governments to have sufficient reserved for domestic use.

The Northern Territory situation has been in the news in recently because of an inquiry into the risks of fracking (hydraulic fracturing) if the industry is allowed to go ahead there.  The current moratorium on the industry and the inquiry is the result of an election pledge by the government elected in August 2016.

If the moratorium is lifted, there will be serious climate  implications according to the Australia Institute. 

In its submission to the inquiry the Institute stated, “Even a 5% increase in Australia’s emissions from a single gasfield is a large and unacceptable increase.  It is completely inconsistent with Australia’s carbon budget and our commitments under the Paris agreement.”

The Institute claimed that burning the NT’s total gas resource would emit 12.2 billion tonnes of carbon dioxide equivalent.

Then there is the problem of fugitive methane emissions from seepage and leaks.  And methane is a much more potent greenhouse gas than carbon dioxide – particularly over shorter periods.

However, carbon emissions are only one of the major problems noted by those who oppose the development of the industry.  Others include concern about water use and contamination of aquifers, the risks to human health and the poor record of the government in ensuring compliance with mining development conditions.

It will be very interesting to see what the NT Government decides.

            - Leonie Blain

 This article was originally published in the VOICES FOR THE EARTH column in The Daily Examiner on March 5, 2018. 

EARTH MATTERS: Grafton Street Tree Heritage - Uniformity and Diversity

Tree Waratah     Photo: Jeff Thomas

Monday March 19

In the first Earth Matters session of the year Jeff Thomas will discuss Grafton trees.  While Grafton is well known for its Jacarandas, there is a lot more to the treescape in the city. From the odd remnant of the original rainforest, early plantings for shade and beautification, a long relationship with the Royal Botanic Gardens Sydney and changing ideas of diversity and avenue plantings Grafton has a rich street heritage which few other towns can rival. 

Jeff Thomas is a NPWS former ranger and currently pest officer. With scientific and horticultural qualifications, he has been interested in the many fine examples of trees in the urban landscape of Grafton, many of which are rarely seen elsewhere

The session will be held in the Staffroom at Grafton Primary School, Queen Street, Grafton from 5.30 – 7 p.m. on Monday March 19.

There will be ample opportunity for questions and discussion.  Refreshments will follow.

For further information, contact Stan on 66449309.

Earth Matters is a session on the environment which is conducted every two months by the Clarence Valley Conservation Coalition ( clarencevcc@gmail.com ).

Golden Penda, Market Square    Photo: Jeff Thomas