Professor Rick Shine of Sydney University recently won the Prime Minister's Science Prize for research into helping northern Australia's peak predators to survive the cane toad invasion.
Cane toads were introduced to the north Queensland sugar cane area in
the 1930s in the mistaken belief that they would eradicate the cane
beetle. Since then they have been steadily spreading south and west. To
the west they have moved across the Queensland savanna into top end of the
Northern Territory ( including into Kakadu National Park) and further
west into the Kimberley region in the north of Western Australia.
Cane toads (Rhinella marina) are poisonous through their life cycle.
As these introduced pests advanced, they brought devastation to native wildlife
which sought to prey on them in the areas they have colonised. Goannas,
snakes, freshwater crocodiles, quolls and dingoes are some of the native
species which have died as a result of the toad's poison. It has
been estimated that up to 95% of native predators have been killed as this
introduced pest moves westward.
Professor Shine became an expert on cane toads while he was researching
snakes on the Adelaide River floodplain south of Darwin in the Northern
Territory. The frontline of the cane toad invasion consists of large, highly
toxic adult males. They are so toxic
that a meal of one toad is sufficient to kill a Yellow-spotted Monitor, a goanna.
In his research Professor Shine has been dropping juvenile toads ahead of
the invasion line. When the native
predators eat these they get sick but do not die as the juveniles are less
toxic. As a result they are less likely
to prey on the larger toads when they arrive.
Initial studies have shown mortality rates dropping below 50% among goannas after the toads arrive.
The professor has further developed his theories working with Dr Ben
Phillips at the University of Melbourne. They have discovered a genetic
variation in toads that governs how quickly they spread.
“Genes that make a toad go faster move to the front,” Professor Shine
said. “The genes that say ‘take a night
off’ stay at the back.”
By dropping slower dispersal juveniles ahead of the fast moving frontline,
the professor is not only training predators not to eat the larger, deadly
toads but is creating a “genetic backburn” to slow down the advance.
Wednesday 26 October 2016
Sunday 16 October 2016
The proposed Carmichael coal mine in central Queensland’s Galilee Basin has recently been given a boost by the Queensland Government which has declared it ‘critical infrastructure’. This designation means fast tracking the remaining project approvals and removing the power of the community to challenge it in court as well as enabling the company to forcibly acquire land.
The last time this designation was given to a development in Queensland was in 2008 when parts of the South East Queensland Water Grid were declared critical infrastructure because water supplies in this heavily populated area were at critically low levels because of drought. There’s a great deal of difference between the critical infrastructure of a water supply grid and a massive coal mine!
The mine, proposed by Indian company Adani, gained most of the necessary state and federal approvals in 2014. However, the project is controversial and has been subject to a number of court challenges.
Two concerns encouraging opponents to undertake court challenges are the threat the mine and its associated port developments (at Abbot Point, 25 km north of Bowen) pose to the Great Barrier Reef and to groundwater in the Basin.
Another major concern is the carbon emissions this project will see released into the atmosphere at a time when the world should be drastically cutting its emissions. When peak production is reached, Adani expects to mine 60 million tonnes of coal per year. Over its estimated 60 year life it expects 2.3 billion tonnes to be extracted. Whether the mine, if it goes ahead, will have a life of 60 years is problematic, given moves around the world to limit coal production, moves which are likely to become more influential in future years as concern rises about the necessity of limiting emissions to combat climate change.
There are other concerns in relation to Adani. These involve corruption, illegal activity, human rights abuses, tax evasion and environmental destruction
(1. The Sydney Morning Herald 3 October 2015 - Adani faces questions over conduct at home
2. Times of India 13 September 2016 - Adani, Essar get DRI notice for overvaluing imports
3. The Sydney Morning Herald 5 September 2014 - Concerns at Barrier Reef contractor's humanitarian, environment record )
While the unsuccessful court challenges may have slowed Adani’s start, another major problem has been its inability to obtain project funding - the result of a very successful lobbying campaign targeting major banks and other financial sources.
The Queensland Government’s recent encouragement stems from concerns about job losses in central Queensland following the general mining downturn in the last year or so. The Government appears to believe the original company spiel of 10,000 jobs - even though Adani’s own economic expert recently put the job number at 1464.
The Queensland Mines Minister Anthony Lynham sees the project starting construction in mid to late 2017.
The Queensland Government should be looking at the big picture. This is not a time when governments should be encouraging the development of new coal mines - particularly one as large as this. Those opposing the mine are concerned that if all the coal from Carmichael was burned, it would register on a global scale - amounting to about 0.5% of the "budget" of carbon dioxide that can be emitted before the world tips past global warming of 2 degrees celsius.
As well as the climate change scenario, the Government - anxious as it apparently is about jobs - should be considering the 69,000 Barrier Reef tourism jobs that will be put at risk by this mine.
Tuesday 11 October 2016
Four hundred years ago Dirk Hartog, a captain with the Dutch East India Company, landed on the Western Australian coast on what is now called Dirk Hartog Island. The island was visited by further explorers including Willem de Vlamingh and William Dampier.
Dirk Hartog Island, now a national park in the Shark Bay World Heritage Area, is Western Australia’s largest island. It is 80 km long and 15 km at its widest point with an area of about 63,000 hectares.
When these early explorers landed on the island there were, according to subfossil records, 13 native mammal species living there. Today there are just three. The local extinctions have been the result of human activity including the introduction of goats, sheep and cats. By 2009, when it became a national park, the island’s goat population had expanded to an estimated 10,000 and the impact of these animals grazing and trampling on the native vegetation had been very severe.
“Return to 1616” is an ambitious $16.3 million project to eradicate all feral animals from the island and return the 10 locally extinct species – including the Woylie, Chuditch (Western Quoll), Dibbler and Western Barred Bandicoot – to the island. There are also plans to introduce two other threatened species, the Banded Hare-wallaby and the Rufous Hare-wallaby, from neighbouring islands in order to aid their conservation.
Two-thirds of the funding for the project comes from an offset which was a condition for Chevron’s Gorgon gas project on Barrow Island and a third from Western Australia’s Department of Parks and Wildlife.
The project has used a variety of methods to remove the feral animals. “Judas” goats wearing radio collars have been used to locate goats for aerial shooting programs. Methods such as pheromone lures and mouse sound effects have been used to trap cats while baiting has also eradicated many of these pests. Infra-red motion cameras and cat-detector dogs have also been used to detect cats.
Species introduction will only take place after the project operators are sure that the cat menace has been completely removed and the native vegetation has had time to recover.
- Leonie Blain
This article was originally published in the VOICES FOR THE EARTH column in The Daily Examiner on September 26, 2016
Saturday 1 October 2016
It is quite feasible for the majority of Clarence Valley landowners to have koalas in their gardens.
The main cause of local koala extinctions is habitat destruction, so it stands to reason that where habitat is returned, koalas also have a chance of returning.
In the Clarence, habitat was initially cleared across the floodplains for agriculture. Now it is for housing, roads, fencing, fire breaks, powerlines, or frequently just for a view. However it can also be by logging state forests or private land, which often removes individual food trees and territorial boundaries. All these activities can make koalas move, mostly into already occupied or unsuitable areas, to cross busy roads they never used to cross, and enter gardens with dogs.
Habitat destruction is also caused by too high fire frequency and uncontrolled burns, which at best kills or dries koalas' food leaves, pushing them into increasingly marginal habitat, but also kills the koalas themselves where tops of trees are scorched.
So anyone thinking to encourage a koala into their yard should assess their area's fire regime, talk to like-minded neighbours, then be ready to ensure any burning is carried out legally, and any fire stays strictly within the boundaries of the person lighting it, to keep koalas safe on the properties they move onto.
Having the right trees of course is also critical. So uncertain landowners should ask at their local environment centre or landcare group if koalas would have historically occupied the land in the first place. They might even get some help in identifying trees, both on and around their land, that will support koalas' fussy feeding habits.
Another focus needs to be on restoring damaged creek and drainage lines and associated floodplains and flats, which supply the vital water in the leaves for koalas, and also form a natural fire-retardant network when in a normal moist condition.
Landowners might also ask about the possibility of a donation of tubestock trees, which are sometimes available free of charge where the person is willing to do the planting.
- Patricia Edwards
This article was originally published in the VOICES FOR THE EARTH column in The Daily Examiner on September 19, 2016