Tag Archives: northern territory

The Impacts of Fire on Wildlife Workshop

Land for Wildlife hosted a Fire Workshop back in May with a focus on Fire and the effects on wildlife, particularly arboreal mammals.

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The subject is of course complex and controversial but vital to the management of our landscapes and the ecology of our native species.

To try a give a balanced perspective we organised a very well known fire ecologist Alan Andersen to present alongside Natalie Rossiter on the findings of fire experiments that have been conducted over several years in bushland at the Territory Wildlife Park and then for participants to be given an insight into the effect of fire on Wildlife and landscapes from a land manager’s point of view with Andrew Spiers giving a walk and talk, who also has many years of land management experience from National Parks and teaching and observing in the field.  There are of course many other experts in fire and many studies and perspectives to consider.

Over 20 people attended the workshop, including fire volunteer and land managers. They were shown the fire plots at The Territory Wildlife Park and then invited for a walk and talk on Andrew Spier’s property on the nearby Blackmore River flood plain. Greg Miles also attended and offered his perspective from being a long term ranger and Land Manager in Kakadu as well as managing his own Land for Wildlife property.

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Often it is perceived that there is too much fire in our landscapes in the Top End, often started by people with little knowledge of fire ecology (such as people out on quad bikes having fun or just driving along). Many preventative “prescribed” burns are carried out to induce an early (dry season) cool burn rather than a later hotter “accidental” burn when winds are higher and fuel load is drier.

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Gamba grass is a huge factor in affecting the fire regime. (see below). Fire management or regime involves the factors of frequency, patch size and shape burnt and fuel load (related to time of year) and conditions (dew point, wind etc. also related to time of year)

IN Summary-

  • Savannah Landscapes have been shaped by fire over a very long time in Australia to be dominant in species with fire survival mechanisms that thrive with fire such as Eucalypts and grasses.
  • Riverine areas, Monsoon forests and wet lands are more sensitive areas of vegetation and frequent fire does not allow them to regenerate as a Savannah landscape does. Often as these landscapes are bordered by woodland there can be a knock on or edge effect.
  • Gamba grass is a considerable factor in adding to fuel load and curing only to burn later, when fire is hot and to intense for other native species to recover.
  • The fire experiments have found that burns on the same area of bushland every 4 years (early or even later on) creates greater biodiversity (Andrew Andersen)
  • The longer term ecological interactions of species is the important factor that fire effects rather than the immediate effect on wildlife (Andrew Andersen)
  • Fire effects different species differently, there are some winners and some losers (AA)
  • Generally when fire is absent the tree layer becomes more mature and dense and fire sensitive species start to colonise, the grass layer reduces.
  • In the case of arboreal mammals, the absence of fire is favourable as mid-story fruiting plants, rainforest fruiting plants are more abundant as a food source and old growth trees stand for longer and harbour hollows.
  • It is very difficult to manage fire on a large property as there are many “Wild fires” which are uninvited. Many flowering plants are lost when this happens on the floodplains.
  • It really is down to the land manager to decide how they shape the landscape they manage with (or without) fire
  • Greg Miles introduced the idea of wet season burning, which we may invite LFW members to learn more about later in the year, below is a short summary:

Most land managers have adopted the advice of fire experts and been doing early dry season burning (EDS) for the protection of assets and to prevent destructive late season fires (LDS) later in the year.  While there are very good reasons to use EDS for this purpose, I would argue that what suites asset protection may not suit the natural ecology.  After 40 years of involvement in natural area fire management I have come to the view that EDS burning is cumulatively killing the woodlands of the Top End.  There is a mountain of circumstantial evidence to support this hypothesis, but it is contradicted in part by some research findings, especially CSIRO’s Kapalga Fire Experiment of the 1980’s.  But it is clear to me that frequent EDS burning promotes annual grasses, especially native speargrass.  Burning encourages more grassy fuel which encourages hotter burning which encourages more grass – ad infinitum.  Thus a “grass fire cycle” is created.  This cycle is improving the hunting success of cats and is slowly killing the pre-European ecology of the woodlands.  Add in Cane Toads and invasive African Grasses and you have the perfect storm.  But there is a way to break the grass fuel cycle.  In my view the solution is to reduce the amount of EDS burning and instead, dramatically increase the amount of early wet season burning (EWS).  Sure there are many practical problems with doing this, but they can be managed.  WSB is more intellectually demanding than EDS burning, but that should not be seen as a reason not to do it.  My prediction is that if land managers were to switch from EDS to EWS burning they would see a rapid turn around in the ecological health of the natural woodlands landscape.

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If you would like copies of any papers or presentations by Alan Andersen, Greg Miles or Andrew Spiers please contact Emma Lupin (elupin@greeningaustralia.org.au)

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Top End Wildlife- Children’s Books- The Quoll

We have some very talented artists and story tellers in the Top End, and what better way to get the next generation to value our wildlife and landscapes and the connectivity between species,  than to intrigue and educate them through books, here is just the first of  a few great titles that we will feature.. .

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Sandra Kendall, Darwin resident and artist has written several books with a focus on loving our landscapes and the wildlife within-
My main aim is providing accessible images and stories for children about native wildlife to entertain and educate. The last couple of books have focused on urban wildlife to provide stories that Top End kids can claim particular affinity with with the hope that in turn this will stimulate interest in other local species. 

My first book “Quoll” (published by Windy Hollow Books 2008) was inspired by the Island Ark Project, a collaboration between Biodiversity North, The Territory Wildlife Park and The Gumurr Marthakal Rangers aiming to preserve a healthy population of Northern Quoll on offshore islands as the arrival of Cane Toads in Top End was pushing the species to the brink of extinction. The story of one quolls plight is told from the animals point of view as she tries to save her family from the Cane Toad ‘invasion’.

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(Scientific information about the Northern Quoll for the book was kindly provided by Dr John Woinarski in the info pages following the narrative)

The Northern Quoll (Dasyurus hallucatus) is a mammal native to northern Australia which weighs 300g- 1000g and has prominent white spots on its fur. It is carnivorous and eats a range of invertebrates including reptiles. It’s habitat is hollow logs, tree hollows and rock crevices.  

The Northern Quoll is listed as critically endangered in the Northern Territory and is listed as endangered within Australia as a whole. It has been recorded as rapidly declining in numbers over the last few decades. This decline is largely attributed to the introduction and spread of cane toads but also is affected by frequent and late season burning, which causes habitat loss.

In the Northern Territory the quoll is  restricted to the Top End. To assist its recovery private landholders can implement a Cane Toad eradication  program, prevent the loss of habitat, particularly tree hollows by protecting landscapes from hot fires and even create and place tree hollows with the property.


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For more information a fact sheet can be found here https://nt.gov.au/__data/assets/pdf_file/0005/205475/northern-quoll.pdf

A virgin Virginia Block

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Land for Wildlife member David Rolfe tells the story of his 2 hectare block in Virginia-

In 1992 this was an undeveloped block of 2 hectares with a surprising range of habitats; a very rocky ridge with low savannah, a steep slope over a tumble of rocks, a sheltered area beneath the rocks and a wet season lagoon with a variety of melaleucas.

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It adjoins two largely uncleared bocks, one is 2 hectares, another is 11 hectares, and both of which include the lagoon area as well.

Most of the block is uncleared. With some difficulty a part of the block on the ridge was cleared for the house, a shed and enough of a landscaped area to see the snakes coming across the lawn! Sadly, some of the original species (snakes, goannas and quolls) have disappeared because of cane toads, and development of course. There was also a lot of feral grasses which had to be eliminated, but this also meant that finches lost a source of food, and they are now not common.

However, there are plenty of wallabies and bandicoots, and a great variety of honeyeaters and fruit eating birds. Scrub fowls have also set up a mound at the edge of the garden and owls frequent the rainforest trees. There are a variety of flycatchers and varied trillers regularly visit. Seasonal visitors are the Emerald Ground Pigeon and the Torres Strait Pigeon. In the wet season swamp Rajah Sheldrake ducks and grebes nest and raise young.

Some areas have been planted with rainforest and native fruit trees, and these are now nearly mature. As far as possible native plants from the NT or north Australia are used for planting. There is a shade house used for propagation and for vegetables and fruit trees such a bananas and paw paws.

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Two small ponds have been established and a bog. Another small bog is to be completed.

Some future plantings will involve understory plants, grasses to attract finches and plants to sustain and develop habitat for butterflies and moths. Ongoing maintenance includes the removal of invasive trees that threaten to overrun the original vegetation or with other adverse effects: Black Wattle, Cassia, Alphitonia, Neem tree and Curry tree.

David signed up to Land for Wildlife in 2013