Fire Management on Pastoral Properties in Central Cape York Peninsula

Why manage fire Large areas of Cape York Peninsula are burnt each year, mostly by late dry season fires. The map below shows how often Cape York Peninsula was burnt by late dry season fires in the nine years from 1997 to 2005. Some areas, mostly rainforest, were never burnt by wildfires in this period; others were burnt nearly every year.

Properties on Central Cape York Peninsula were burnt by wildfire less often than were properties on the western side of the peninsula. This is largely because most land managers in the region undertook active fire management. Most land managers in central Cape York Peninsula say that, if they did not burn fire breaks in the early dry season, their properties would also be regularly burnt out by extensive wildfires late in the year.

Poor fire management can lead to loss of forage and vegetation thickening, thereby reducing the viability of cattle properties. It can also cause loss of habitat for native plants and animals. Details about the impacts of fire are presented in this leaflet, along with guidelines on the best ways to manage fire, based on the experience of local land managers and scientists. The leaflet also uses a make-believe property called Pretend Plains to demonstrate best practice fire management for central Cape York Peninsula. This advice can be adapted to suit other areas of the peninsula.

Late dry season fires Fire-scar data from www.firenorth.org.au based on NOAA satellite imagery.

This leaflet has been prepared by Gabriel Crowley & Mandy Trueman (Tropical Savannas CRC) with information from local pastoralists, pastoral advisors, fire managers and ecologists. Thanks are extended to all who contributed, especially Wendy Seabrook & Sandy Lloyd (Cape York Peninsula Landcare Program), Stephen Garnett (Charles Darwin University), Tom & Sue Shephard (Artemis), Peter Thompson & Stephen Hall (Cape York Sustainable Fire Management Project), Joe Rolfe (Queensland Department of Primary Industries and Fisheries), Brian Lynch (Northern Territory Bushfires Council), Eda Addicott (Queensland Environmental Protection Agency), and Joe Miller (pastoral consultant).

Impacts of fires in different seasons

Benefits Disadvantages Fires lit in the early dry season Fires lit in the early dry season help prevent the

spread of late dry season wildfires by removing ground layer fuel. Burnt strips of ground can form a network of control lines along with other barriers, such as roads, tracks and rivers. When lit late in the afternoon, early dry season fires are likely to go out overnight, so are easy to control.

These fires can cause vegetation thickening by removing grasses that compete with woody regrowth. Woody plants draw on soil moisture through the dry season, so will already be above the grasses that resprout with the first rains. These fires can also damage actively growing perennial grasses and cause their replacement by annual grasses.

Fires lit in the mid-dry season Fires lit in the mid-dry season may be useful to help

extend fire breaks if there is already a network of early burn established.

These fires may get out of control and burn for several weeks. Fires lit in the mid-dry season can contribute to vegetation thickening

Fires lit in the late dry season Fires lit in the late dry season can maintain and

restore open vegetation structure. They can help to create nesting hollows in the tops of trees that are needed by hollow-nesting birds and mammals.

These fires are extremely difficult to control, and can burn extensive areas of pasture and eliminate native animals by destroying large areas of habitat. They also expose soil to erosion, may destroy canopy trees, and can endanger human life and property.

Storm-burns (lit after the first wet season downpour) When used skilfully, storm-burns help restore open

vegetation communities without causing extensive damage to forage, habitats or canopy. Storm-burns are most effective when lit 2-3 days after the first heavy storm, when the sap has risen in woody plants, but before most grass seed has germinated.

Timing of storm-burns can be difficult, and impossible in years when the first rains are widespread and persistent. Storm-burns can spread uncontrollably if lit when rain has been insufficient or patchy. If lit too long after the first rains, they can cause loss of ground cover and soil erosion.

Storm-burns rarely reach the canopy, but clean up the suckers © Stephen Garnett 2

Things to consider

Protecting feed for the year If a wildfire starts in the late dry season, it may not stop until it reaches a permanent river or major road. If large areas of pasture are burnt, cattle must be moved out of the burnt areas and fed hay and lick to keep them alive. The need to control such fires by back-burning can mean even more country is lost, and much time is lost in fire-fighting. Fire breaks are needed to prevent these losses. Experienced pastoralists do this by burning no more than 10% of a property in a strategic manner in the early dry season. Although they lose some high quality green feed, they prevent losses of much greater areas of, admittedly lower quality, feed to late dry season fires.

Animal health - different opinions Control of cattle ticks relies on good cattle management, especially spelling areas from grazing animals. Many pastoralists on the peninsula also undertake tick control by burning areas of old grass, particularly at storm-time. Some people think that feeding on green pick improves animal health - others that cattle do poorly if they stay on areas of green pick too long. Cattle that are in poor condition at the end of the dry season may not survive the break in the weather. Some pastoralists believe cattle die at this time of the year if they get colic from suddenly changing from feeding on burnt ground to green grass. Brahman cattle ©Kerry Shephard

Vegetation thickening Leaving country unburnt, or burning regularly in the early dry season, along with overgrazing, can lead to vegetation thickening. In the space of 10 to 15 years, it is possible for open country to become completely impassable. Country types most at risk are open flats and ti-tree flats (see p 5). Thickened country is hard to muster in. Open grassy flats can support four times as many cattle as flats covered by ti-tree. On Cape York Peninsula, thickened flats are also poor habitat for wildlife (see below). Ti-tree invaded flat ©Stephen Garnett

Wildlife needs patchy fires Animals that need grass, leaf-litter, or low shrubs to nest and shelter in, or that feed on fruits, flowers, or insects under the bark of trees, cannot survive in burnt areas. When fires are small, animals can retreat to nearby unburnt habitat, and recolonise when the vegetation recovers. If large areas are burnt, these fire-sensitive animals may disappear from an area altogether. Some animals are attracted to feed in burnt areas, where food can be easier to find, but no animals are entirely dependent on them.

Brown Treecreepers feed on

insects that live in the bark of trees © Ian Montgomery

Sugar Gliders need blossoms for food

© Euan Ritchie

Vegetation thickening and wildlife Some animals need open vegetation to live in. They may rely on the grasses and their seeds for food, or they may simply be better able to avoid the attention of predators that lurk in dense vegetation. For example, Golden-shouldered Parrots cannot survive in thickened country because the antbeds they nest in are shaded-out, and many nesting birds are killed when butcherbirds ambush them from the branches of nearby small trees.

Pied Butcherbirds are more successful at

hunting Golden- shouldered Parrots in dense vegetation

©Roland & Julia Seitre

Golden-shouldered parrots

nest in antbeds on open grassy flats © Sam Abell

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Best practice fire management for country

Sandridges Sandridges are the dominant country type in central Cape York Peninsula. The main plants that are important to cattle are the perennial grasses Sorghum, Giant Spear, Cockatoo Grass and annual Fire Grass. Perennials need occasional spelling to keep their vigour, and to prevent their replacement by Hyptis. The seeds of Fire Grass are important food for seed-eating birds through the dry season. The seeds of perennial grasses are important in the wet season, when other seeds are scarce. The dominant trees, particularly messmate, tend to sucker if burnt in the early dry season, crowding the understorey. But this does not appear to lead to a greater density of

saplings or adult trees. Do not burn sandridges when grasses are actively growing. Use early burning to focus grazing away from overgrazed areas. If burning to promote green pick, do not allow cattle to overgraze. Burn different areas each year. Storm-burn to keep understorey clear of suckers. Make sure each fire covers only a small area so that animals can recolonise quickly. (Regional Ecosystems: 3.5.1, 3.5.7a, 3.5.7x2, 3.5.12, 3.3.58)

Sandridge after spelling © Susan Shephard

Gravel slopes The edges of the ranges often have shallow gravelly soils and a sparse, but diverse tree cover that includes ti-trees, ghost gums and quinine. Fire Grass dominates the ground cover, but there are pockets of Sorghum, Giant Spear and Cockatoo Grass. The perennial grasses need wet season spelling from grazing to maintain their vigour and prevent their replacement by Hyptis. As they are well-drained, seed persists in rock crevices even when most other seed has germinated. This makes gravel slopes important habitat for seed-eating birds in the early wet season. Ti-tree invasion of gravel slopes is slower than in the lowlands, but difficult to reverse, especially in areas grazed by stock.

In ungrazed areas, or where spelling allows a build up of grassy fuels, storm-burning every four to five years may be sufficient to keep these areas open. In grazed areas, more frequent burning is required. (Regional Ecosystems: 3.11.10a)

Gravel slopes © Susan Shephard

Ironbark ranges Ironbark ranges support dense stands of Black Spear Grass. This grass is very robust, and benefits from storm-burning every three to four years. As cattle like to graze in the hills over the wet season, high stocking rates may be a problem. However overstocking is unusual, because difficult access discourages fencing of this rugged country. Inaccessibility also creates fire management problems. Aerial Control Burning in the early dry season may be the best way to prevent widespread wildfires later in the year. (Regional Ecosystems: 3.11.8, 3.11.9, 3.11.11)

Black Spear Grass on hills © Susan Shephard

Box flats Box flats in central Cape York Peninsula have a good covering of perennial grasses, notably Sorghum and Kangaroo Grass. These flats are not usually subject to vegetation thickening, but they do need spelling from grazing to maintain the vigour of the productive perennial grasses. The best way to protect these productive grasslands from wildfires may be to burn the sandridges either side. Storm-burning may be used to remove rank grass and reduce fuel loads and fire risk. (Regional Ecosystems: 3.3.25a, 3.3.36)

Visit www.epa.qld.gov.au for details of Regional Ecosystem map units Box flat © J.R. Clarkson and V.J. Neldner

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types of central Cape York Peninsula

Ti-tree flats Ti-tree flats rapidly thicken with ti-tree suckers, and are then of little value for grazing, or for the plants and animals that depend on them. The main grass Wanderrie Grass is not very valuable as a forage species, but is supplemented with patches of perennial Sorghum and Cockatoo Grass where flats have not been over-grazed. The best way to keep this country open is to spell it from grazing for a growing season to allow a build-up of grassy fuel, then to burn it soon after the first storms (see p 2). Storm-burning can reduce suckers, but has little or no effect on trees greater then 2 m tall. It is also important not to over-graze or burn the country too often, as this will reduce the abundance of quality perennial grasses, and the fuel loads needed to ensure a clean storm-burn. (Regional Ecosystems: 3.3.33, 3.3.42, 3.5.14, 3.3.52, 3.5.17, 3.5.14, 3.3.47)

Ti-tree flat after storm-burning © Gabriel Crowley

Open flats Open flats support a healthy growth of Sorghum and both annual and perennial Kangaroo Grasses. They stay green late into the year. These grasses are valuable for cattle, but prone to overgrazing. They need periodic wet season spelling to maintain them. Open flats are also susceptible to invasion by ti-tree suckers, even more so if over-grazed. Golden-shouldered parrots that nest in antbeds on open flats are more successful than those that nests on thickened ti-tree flats. Manage open flats by wet season spelling and storm-burning. In the early dry season, avoid burning open flats, as it promotes thickening. Instead burn the sandridges either side to create firebreaks. (Regional Ecosystems: 3.3.48, 3.3.56) Open flat © Susan Shephard

Swamps Although swamps may be considered to have a high carrying capacity for cattle, as they provide green feed for most of the year, grazing and trampling by pigs and cattle reduces water quality and the conservation values of these areas. Swamps that dry out late in the year are not usually damaged by fires, which can help to remove rank growth. More permanent swamps in central Cape York Peninsula do not appear to be threatened by fire. (Regional Ecosystem: 3.3.14)

Swamp on a sandridge © Gabriel Crowley

Scrub Scrub has very little pastoral value. Scrub along major watercourses is best fenced out from stock and pigs to protect both the ecological values and water quality. Scrub is rarely threatened by fire in the central peninsula. It is fairly fire-resistant and acts as a natural fire break. The value of these breaks can be increased by burning the adjoining drier sandridges early in the dry season. Scrubs on hills and sandridges in this region are rarely threatened by fire, as there is usually little grass to act as fuel. If properties are well managed to minimise late dry season wildfires, additional management is usually unnecessary to protect scrubs. However, where late dry season fires repeatedly damage scrubs, it is a good idea to burn low intensity fires around them in the early dry season. (Regional Ecosystems: 3.5.20, 3.7.1, 3.11.2b, 3.3.10)

Streamside scrub © Susan Shephard

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Approaches to fire management,

Pretend Plains, a make-believe 1096 km2 property on central Cape York Peninsula

This property has been designed with the main country types and features of a typical cattle station on central Cape York Peninsula. It provides an example of fire management that can be adapted to suit local conditions.

Getting burnt-out

The most damaging fires for both grazing and biodiversity values are those that start in or after September. These fires spread quickly, and can burn through narrow breaks. They will continue to spread until rains come, possibly until Christmas or even later. Fires from the south-east will spread rapidly because that is the main direction of the dry season winds. Fires from the west will spread more slowly, but may produce a more complete burn. Fires can also start on the property. Main roads, or areas visited by pig hunters, campers or fossickers are areas where fires are particularly likely to start. The map on the right shows the spread of a couple of wildfires that burnt about 60% of Pretend Plains in one year. A fire year like this could be disastrous for the cattle, native plants and animals, and the viability of the property.

Example of losses to extensive late dry season fires on Pretend Plains

Strategic burning in the early dry season will help to prevent this occurring

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Areas burnt for fire management on Pretend Plains over a four-year period The pattern of burning used ensures there are breaks that will help stop the spread of late dry season fires, but avoids burning the same areas every year. This helps to spell country from grazing pressure, keeps native perennial grasses in a healthy condition, and minimises vegetation thickening. Burning

alternate sides of the river in the northeast bolsters this natural barrier to wildfires. In unfenced country, small areas are burnt around dams to concentrate cattle at mustering time. Storm-burning is used to

maintain open country. This approach addresses the needs of cattle and considers conservation values. See Calendar for fire management on central Cape York Peninsula (p 8) for more details

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using Pretend Plains as an example

Four-yearly rotation of burning activity

Calendar for fire management: Central Cape York Peninsula

Early Dry Season

Create fire breaks to reduce the occurrence and spread of wildfires Identify the main directions that wildfires come from, and create barriers to reduce the risk of them entering your property. On central Cape York Peninsula most fires come from the southeast, so securing the south-eastern boundary is a priority. It is also important to break up the country, so that if there is a wildfire on the property, only a small section is likely to get burnt.

• On Pretend Plains they burn along ridge lines using Aerial Control Burning, making sure not to burn the same ridge each year to avoid vegetation thickening. This is done before the country dries off too much. These breaks are used to reinforce natural barriers made by major creek lines, burning different sides of the creek each year.

• They check the Firenorth website www.firenorth.org.au to find any gaps in the fire breaks. Then fill in the gaps using on-ground burning.

• They grade or slash all of their tracks to make effective fire breaks Use fire to control cattle movements As cattle are attracted to recently burnt ground, some pastoralists in central Cape York Peninsula burn at mustering time to bring in cattle. This practice is becoming less popular as land managers are more concerned about vegetation thickening, and as more country is fenced.

• On Pretend Plains, they burn around dams at mustering time to concentrate cattle, but only in unfenced country and are careful not to burn the same areas each year. They are progressively fencing paddocks and building trap yards to reduce the need for this type of burning, as well as to improve cattle management.

Mid to Late Dry Season

Watch for fires and try to restrict the spread of any fires on the property Wildfires can threaten the property any time from August onwards. A rapid response to such fires can restrict the amount of damage they have on cattle and wildlife.

• On Pretend Plains, they regularly check the Firenorth website for fires www.firenorth.org.au. • When fires threaten, they back-burn into them, burning away from permanent streams, graded

tracks and previously burnt breaks.

First heavy storms

Use fire to maintain or restore the country’s open structure Storm-burning after spelling from grazing is useful for maintaining open country, but needs to be undertaken with care (see page 2)

• On Pretend Plains they wait for 2-3 days after the first rains of an inch or more, then burn areas that are prone to thickening by suckers, burning up to one quarter of the property each year. Before lighting up, they make sure that either fire breaks or very wet conditions will prevent the fires spreading outside the areas they intend to burn

Follow same pattern of burning each year, changing the areas that are burnt, so that individual areas do not get burnt more than once every two to five years, depending on country type (see pages 4-5).

To get further copies of this leaflet

You can download a copy of this leaflet as a PDF file from the Tropical Savannas Cooperative Research Centre’s North Australian Land Manager website (www.landmanager.org.au). Botanical names used in this leaflet can also be found on this website.

Contact details for getting help with fire, cattle and biodiversity management

Cape York Sustainable Fire Management Project Phone: 4031 3432 Email: cypda@cypda.com.au

Cape York Peninsula Landcare Program Phone: 4069 5046 Email: landcare@capeyorks.com

Queensland Department of Primary Industries & Fisheries, Mareeba Phone: 4048 4600

Queensland Rural Fire Service Phone: 4039 8240 Website: www.ruralfire.qld.gov.au

Queensland Parks & Wildlife Service, Atherton Phone: 4091 8191

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