Download Birds Australia Wingspan Supplement 7 Fire and Birds

F I R E AND
B I R DS
Fire Management for Biodiversity
Compiled by
Penny Olsen and Michael Weston
Supplement to Wingspan, vol. 15, no. 3,
September 2005
2
Fire and Birds
Fire and Birds
3
‘Fire is a force in terrestrial ecosystems that is equalled only by the impact of humans as they transform,
fragment and degrade the Earth’s vegetation… Regardless of the changes wrought, fire is a central process in
creating and maintaining ecosystem patterns and processes in most, if not all, Australian terrestrial ecosystems.’
John Woinarski & Harry Recher 1997
Fire is part of Australians’ heritage—it has and continues to shape much of our natural world. Historically,
a fine-scale mosaic of different aged burns predominated, but since the early 20th century there has been
an increase in hotter, extensive fires, more threatening from both a human and biodiversity perspective.
Such inappropriate fire regimes, including the exclusion of fire, threaten over 50 bird species and subspecies
and, since European settlement, have contributed to the extinction of two species. Yet inappropriate
management of fire is one of the most tractable of the major threats to Australia’s wildlife. To some extent
the old adage ‘fight fire with fire’ applies. Used well, fire is an effective, economical tool for land managers.
Reintroduction of occasional fire into some landscapes, and return to a finer mosaic of burning, will
not prevent wildfires; it may, however, reduce their impact, by maintaining fire-dependent habitat and
protecting fire-sensitive birds. There will always be uncertainty, but by striving for practical and effective fire
management objectives we can better manage the risks to both human life and property, and biodiversity.
Fire regime—the pattern of fire in a particular area over a number of years, including seasonality,
frequency, interval between fires, intensity, extent and patchiness
Above: Black Kites at a grassfire in the Kimberley, Western Australia, catching animals flushed by the smoke and flames. Photo by Dennis Sarson, Lochman Transparencies
Left: The habitat of the Southern Emu-wren is vulnerable to wildfires in the dry seasons, but also threatened by deliberate burning for pasture. Photo by Nicholas Birks
KEY POINTS
• Fire is an essential, natural force in the
Australian landscape. Every year the
continent has a large number of wildfires,
caused by lightning or humans. Most are
not regarded as disasters.
• Biodiversity loss is associated with high
fire frequency, intense broadscale fire,
and fire exclusion, all of which tend to
homogenise the landscape. Increasing
loss of habitat heterogeneity from the
landscape is the single most damaging
effect of poor fire management.
• Some 50 bird taxa and their habitats
are currently threatened by inadequate,
ill-informed fire management.
• The response of birds to fire is influenced by
their life history characteristics and habitat
needs. Hence, individual species may vary
in their response to fire, and particular
fire regimes (including fire exclusion) are
essential to the survival of some species.
• The remaining populations of birds
most threatened by inappropriate fire
management occur in coastal heath and
thickets, mallee and northern grasslands
and woodlands—often areas of low
human population.
• Land managers are seeking to incorporate
ecological requirements into their
management decisions and actions, and
most States and Territories now require
land managers to manage fire in fire-prone
vegetation, and to use fire in ecologically
sustainable ways.
• Fire management can generally be
incorporated into management plans
in such a way that neither biodiversity
conservation nor other goals, particularly
protection of human life and property, are
sacrificed.
• It is important to identify regimes known
or suspected to cause biodiversity and
threatened species loss and manage the
land to avoid these regimes.
• Maintaining a mosaic of habitats of
different fire ages is recommended for
large area fire management, but where
habitats are small, fragmented and
isolated, the options are fewer and the
issues more complex.
• Across the north, regulation of exotic
pasture grasses is a high priority for
fire management and biodiversity
conservation.
• Fire management must be ongoing and
adequately resourced.
• There is a need for greater awareness,
research and understanding of the role of
fire in natural systems.
• In the absence of complete knowledge
to guide management, it is prudent to
apply the precautionary principle (that
is, pursue the fire regime that is likely to
be lowest risk in terms of environmental
damage) and adaptive management.
• There is a need for a set of simple, flexible
guidelines to help land managers manage
fire for biodiversity conservation.
OVERVIEW
Birds to Watch
For several bird species an inappropriate fire
regime is the only major threat to their survival.
Without continued implementation of effective
fire regimes, these species are likely to move
closer to extinction in the near future. They
include: the Ground Parrot, Noisy Scrub-bird,
Eastern Bristlebird, Western Bristlebird and
Western Whipbird. The Partridge Pigeon,
Malleefowl, Golden-shouldered Parrot,
Black-eared Miner and, possibly, the Night
Parrot are also at great risk from inappropriate
fire regimes, among other threats.
Inappropriate fire regimes are the
greatest threat to Australia’s birds
after direct human destruction and
alteration of habitats. Potentially, they
are also one of the most manageable of
threats. The introductory pages of this
supplement summarise the key points
from a diffuse and often contradictory
literature on the interaction between
fire and birds. They are complemented
by stand-alone narratives authored by
ecologists concerned that we are
often failing in our management of
fire. While there is certainty that current
fire regimes are often damaging to the
land and its wildlife, there is still much
to learn about effective fire management
to conserve biodiversity. Our hope is
that this report will lead to greater
awareness of the issues, implementation
of bird and biodiversity-friendly fire
management regimes, and refinement
in knowledge of appropriate burning
practices.
Australia has long been a dry,
fire-prone country and for some
60,000 years people have used fire to
manipulate the continent’s vegetation
and wildlife. So commonplace is fire
that much of the Australian biota has
adjusted to occasional burning.
‘You got to burn the country… not leave
him until he really dry, that means you
destroy everything… cook it… Soon as wet
season stop… grass starting to dry out, you
burn grass then… so you don’t burn all the
animals… if you burn it [then], some have
a place to hide, but if you leave him, and
you burn the grass you kill everything, that’s
no good.’
Musso Harvey of the Yanyuwa
people of the Gulf of Carpentaria
(quoted in Baker 2003)
‘Fire, grass, kangaroos and human
inhabitants seem all dependent on each
other for existence in Australia, for any one
of these being wanting, the others could no
longer continue.’
Sir Thomas Mitchell, Journal of
an Expedition into the Interior
of Australia (1848)
In many habitats, fire histories
and Indigenous explanations reveal a
pre-European landscape of small burnt
patches of various stages of fire succession,
maintained by a system of burning which
controlled the build-up of fuel, and reduced
the incidence of large, intense fires. Since
European occupation the magnitude and
rate of change in human-fire interactions
has increased markedly. In the early
days after settlement, fire exclusion and
suppression was a common practice in
more highly developed areas, but deliberate
burning was used in many outlying
areas to reduce fire hazards or maintain
grazing values.
Contemporary fire regimes have
tended to be either of two extremes:
intense, extensive and uncontrolled wildfire
mainly late in the driest season; or land
seldom burnt. This results in loss of firesensitive species, habitats and patchiness in
intensively burnt areas, or wood thickening
and loss of savanna, granivorous species and
general biodiversity in areas seldom burnt.
Near centres of human population, at the
urban and agricultural interface, Australian
authorities have adopted broad area
burning to reduce fuel loads, and protect
human interests; however, fire may escape,
and arson is also common. Over time these
policies, mistakes and misdemeanours lead
to a loss of heterogeneity and biodiversity
across the landscape.
Until quite recently, European
fire management has been directed at
protection of human life and property.
Now, biodiversity management is seen
as important and there has been a shift
towards its inclusion in legislation,
2
Fire and Birds
Fire and Birds
3
‘Fire is a force in terrestrial ecosystems that is equalled only by the impact of humans as they transform,
fragment and degrade the Earth’s vegetation… Regardless of the changes wrought, fire is a central process in
creating and maintaining ecosystem patterns and processes in most, if not all, Australian terrestrial ecosystems.’
John Woinarski & Harry Recher 1997
Fire is part of Australians’ heritage—it has and continues to shape much of our natural world. Historically,
a fine-scale mosaic of different aged burns predominated, but since the early 20th century there has been
an increase in hotter, extensive fires, more threatening from both a human and biodiversity perspective.
Such inappropriate fire regimes, including the exclusion of fire, threaten over 50 bird species and subspecies
and, since European settlement, have contributed to the extinction of two species. Yet inappropriate
management of fire is one of the most tractable of the major threats to Australia’s wildlife. To some extent
the old adage ‘fight fire with fire’ applies. Used well, fire is an effective, economical tool for land managers.
Reintroduction of occasional fire into some landscapes, and return to a finer mosaic of burning, will
not prevent wildfires; it may, however, reduce their impact, by maintaining fire-dependent habitat and
protecting fire-sensitive birds. There will always be uncertainty, but by striving for practical and effective fire
management objectives we can better manage the risks to both human life and property, and biodiversity.
Fire regime—the pattern of fire in a particular area over a number of years, including seasonality,
frequency, interval between fires, intensity, extent and patchiness
Above: Black Kites at a grassfire in the Kimberley, Western Australia, catching animals flushed by the smoke and flames. Photo by Dennis Sarson, Lochman Transparencies
Left: The habitat of the Southern Emu-wren is vulnerable to wildfires in the dry seasons, but also threatened by deliberate burning for pasture. Photo by Nicholas Birks
KEY POINTS
• Fire is an essential, natural force in the
Australian landscape. Every year the
continent has a large number of wildfires,
caused by lightning or humans. Most are
not regarded as disasters.
• Biodiversity loss is associated with high
fire frequency, intense broadscale fire,
and fire exclusion, all of which tend to
homogenise the landscape. Increasing
loss of habitat heterogeneity from the
landscape is the single most damaging
effect of poor fire management.
• Some 50 bird taxa and their habitats
are currently threatened by inadequate,
ill-informed fire management.
• The response of birds to fire is influenced by
their life history characteristics and habitat
needs. Hence, individual species may vary
in their response to fire, and particular
fire regimes (including fire exclusion) are
essential to the survival of some species.
• The remaining populations of birds
most threatened by inappropriate fire
management occur in coastal heath and
thickets, mallee and northern grasslands
and woodlands—often areas of low
human population.
• Land managers are seeking to incorporate
ecological requirements into their
management decisions and actions, and
most States and Territories now require
land managers to manage fire in fire-prone
vegetation, and to use fire in ecologically
sustainable ways.
• Fire management can generally be
incorporated into management plans
in such a way that neither biodiversity
conservation nor other goals, particularly
protection of human life and property, are
sacrificed.
• It is important to identify regimes known
or suspected to cause biodiversity and
threatened species loss and manage the
land to avoid these regimes.
• Maintaining a mosaic of habitats of
different fire ages is recommended for
large area fire management, but where
habitats are small, fragmented and
isolated, the options are fewer and the
issues more complex.
• Across the north, regulation of exotic
pasture grasses is a high priority for
fire management and biodiversity
conservation.
• Fire management must be ongoing and
adequately resourced.
• There is a need for greater awareness,
research and understanding of the role of
fire in natural systems.
• In the absence of complete knowledge
to guide management, it is prudent to
apply the precautionary principle (that
is, pursue the fire regime that is likely to
be lowest risk in terms of environmental
damage) and adaptive management.
• There is a need for a set of simple, flexible
guidelines to help land managers manage
fire for biodiversity conservation.
OVERVIEW
Birds to Watch
For several bird species an inappropriate fire
regime is the only major threat to their survival.
Without continued implementation of effective
fire regimes, these species are likely to move
closer to extinction in the near future. They
include: the Ground Parrot, Noisy Scrub-bird,
Eastern Bristlebird, Western Bristlebird and
Western Whipbird. The Partridge Pigeon,
Malleefowl, Golden-shouldered Parrot,
Black-eared Miner and, possibly, the Night
Parrot are also at great risk from inappropriate
fire regimes, among other threats.
Inappropriate fire regimes are the
greatest threat to Australia’s birds
after direct human destruction and
alteration of habitats. Potentially, they
are also one of the most manageable of
threats. The introductory pages of this
supplement summarise the key points
from a diffuse and often contradictory
literature on the interaction between
fire and birds. They are complemented
by stand-alone narratives authored by
ecologists concerned that we are
often failing in our management of
fire. While there is certainty that current
fire regimes are often damaging to the
land and its wildlife, there is still much
to learn about effective fire management
to conserve biodiversity. Our hope is
that this report will lead to greater
awareness of the issues, implementation
of bird and biodiversity-friendly fire
management regimes, and refinement
in knowledge of appropriate burning
practices.
Australia has long been a dry,
fire-prone country and for some
60,000 years people have used fire to
manipulate the continent’s vegetation
and wildlife. So commonplace is fire
that much of the Australian biota has
adjusted to occasional burning.
‘You got to burn the country… not leave
him until he really dry, that means you
destroy everything… cook it… Soon as wet
season stop… grass starting to dry out, you
burn grass then… so you don’t burn all the
animals… if you burn it [then], some have
a place to hide, but if you leave him, and
you burn the grass you kill everything, that’s
no good.’
Musso Harvey of the Yanyuwa
people of the Gulf of Carpentaria
(quoted in Baker 2003)
‘Fire, grass, kangaroos and human
inhabitants seem all dependent on each
other for existence in Australia, for any one
of these being wanting, the others could no
longer continue.’
Sir Thomas Mitchell, Journal of
an Expedition into the Interior
of Australia (1848)
In many habitats, fire histories
and Indigenous explanations reveal a
pre-European landscape of small burnt
patches of various stages of fire succession,
maintained by a system of burning which
controlled the build-up of fuel, and reduced
the incidence of large, intense fires. Since
European occupation the magnitude and
rate of change in human-fire interactions
has increased markedly. In the early
days after settlement, fire exclusion and
suppression was a common practice in
more highly developed areas, but deliberate
burning was used in many outlying
areas to reduce fire hazards or maintain
grazing values.
Contemporary fire regimes have
tended to be either of two extremes:
intense, extensive and uncontrolled wildfire
mainly late in the driest season; or land
seldom burnt. This results in loss of firesensitive species, habitats and patchiness in
intensively burnt areas, or wood thickening
and loss of savanna, granivorous species and
general biodiversity in areas seldom burnt.
Near centres of human population, at the
urban and agricultural interface, Australian
authorities have adopted broad area
burning to reduce fuel loads, and protect
human interests; however, fire may escape,
and arson is also common. Over time these
policies, mistakes and misdemeanours lead
to a loss of heterogeneity and biodiversity
across the landscape.
Until quite recently, European
fire management has been directed at
protection of human life and property.
Now, biodiversity management is seen
as important and there has been a shift
towards its inclusion in legislation,
4
Fire and Birds
Fire and Birds
Responses of birds to a single
fire event
The effects of a fire on bird communities can be
difficult to predict. They vary with fire intensity,
season and extent; the characteristics of the site,
climatic variation before and after; and time
elapsed since fire. Species differ in their response
to fire and individual species vary in their response.
In general, the Australian bush and its wildlife
can cope with single fire events, but over time
frequent, widespread fires change the character of
the landscape and its inhabitants, to the detriment
of fire-sensitive species.
Before, during and after
Flame Robin. Photo by Peter Merritt
Large logs can act as micro fire-breaks, adding
desirable heterogeneity to the habitat, and they
offer refugia for animals in their moist interior.
Regrowth in the early succession stages after fires,
particularly in the south of the country (here Tiajara,
NSW), attracts small insect-eaters such as Scarlet and
Flame Robins. Photo by Graeme Chapman
Some definitions
Backburning: a fire that is intentionally lit to
consume fuel in the path of a wildfire.
Bushfire or wildfire: a general term used to
describe a fire in native vegetation.
Prescribed, controlled, fuel reduction,
or planned burning: a fire lit under specified
(i.e. relatively safe) environmental and
weather conditions to burn over a
predetermined area, at a time, intensity
and rate of spread necessary to achieve
particular management objectives.
Fire-break: any natural or constructed discontinuity in fuel used to break up, stop or
control the spread of a fire.
Fire age: the time elapsed since the last fire.
Fire intensity: the amount of energy released
per unit length of the fire front, usually
expressed as kilowatts (kW) per metre.
Fire regime: the history of fire in a particular
area, comprising the frequency, intensity,
season of burning (i.e. the time of year a
fire occurs) and the type.
Type: refers to whether the fire is above-ground
or below-ground (i.e. a peat fire), but as
almost all fires in Australia are aboveground this component is usually irrelevant.
Fire succession: the series of stages that
vegetation goes through in its recovery
post-fire.
Fuel load: the amount of combustible material,
especially easily ignitable material.
Hazard reduction burn: a fire intentionally lit to
reduce the amount of fuel, and consequently
reduce the risk posed by wildfires. Fuel is any
material, such as bark, leaf litter and living
vegetation, which will burn.
Trittering: mowing and mulching which
involves pulverising the leaf litter so that it
becomes compacted and burns more slowly
with a reduced flame height.
Adapted from the NSW National Parks & Wildlife
Service Fire Management Manual (2001)
policy and management (see ‘Bushfire
management in the Northern Territory’
p. 16, ‘Tarawi Nature Reserve’ p. 5).
Recent legislation in most Australian States
and Territories not only requires that fire
is managed by land managers in fire-prone
vegetation, but that it is used in ecologically sustainable ways. The importance of
periodic prescribed fire (controlled burns)
to increase or maintain biodiversity is now
widely accepted.
Insights from Indigenous experience
can help inform the development of
effective fire management practices. Sadly,
much of this knowledge has been lost or
eroded. More importantly, landscapes are
now substantially modified from those
managed by Indigenous Australians—by
weed invasion, introduced grasses, grazing,
clearing and drainage; and reduced,
fragmented habitats. These factors
can dramatically alter fire impacts on
landscapes and ecosystems.
‘I am confident that the indiscriminate
burning of bush, which is the concomitant of
all farming and grazing operations, is by a
long way the major cause of the disappearance
of many of our rarer birds.’
Edwin Ashby (1924)
The environmental impacts of fire on
natural ecosystems are not well understood
due to the complexity of the problem,
paucity of research, and megadiversity of
the Australian landscape. There are few
detailed long-term studies of the effects
of fire on avian communities, but there
is sufficient information on fire effects
from a broad cross-section of Australian
habitats to identify patterns of response
to individual fires (see ‘Responses of birds
to fire’ p. 5) and predict likely long-term
effects. Depending on the severity of the
fire, the amount of vegetation burned and
killed, and the weather during the recovery
period, most avian communities recover
rapidly following single fires regardless of fire
intensity. However, even single fires may pose
a significant threat to species with restricted
distribution, limited reproductive potential,
poor dispersal ability and/or narrow habitat
requirements. Birds persisting in fragmented
habitats are particularly at risk because the
whole fragment can burn and, post-fire, small
fragments may not be recolonised by all of
their original species.
Nonetheless, far more threatening
across a broad range of avian communities,
are increases in fire frequency and extent,
on the one hand, and fire exclusion on
the other. These tend to homogenise the
landscape, and offer fewer options for
survival and recolonisation.
Detrimental fire regimes have
contributed to the extinction of two
of the three bird species, and three
of the four subspecies, lost since
European colonisation. Inappropriate
fire management is now a factor in the
threatened status of over 50 nationally
recognised threatened bird species (see table
p. 6). Of those threatened species whose
relationships with fire have been welldocumented, almost all show a preference
for less frequent, less extensive fires than
have occurred in recent decades.
Though the task is daunting, the
costs of inaction are great. Fire can be an
economical way to manage large tracts
of land, on a fine scale, with benefits
to biodiversity and human needs. The
challenge will be to identify and develop
the appropriate fire regimes to maintain
fire-dependent habitats and protect the
fewer fire-sensitive habitats. The single
greatest need for land managers incorporating fire into their management is a
useful tool to determine appropriate fire
regimes (see ‘To burn or not to burn’ and
‘Towards a set of biodiversity-friendly fire
management principles’ p. 6).
‘There was a sound as of thunder, mingled with
the crashes of trees and the wild cries of legions of
birds of all kinds; which fell scorched and blackened
and dead to the ground.’
W. Howitt (1856) describing the
1851 Victorian bushfires
The immediate response to fire by birds depends on
the extent, speed and intensity of the fire; habitat;
and species of bird. It is likely that many birds take
action well in advance, and depart or seek shelter.
Some birds are overcome by the heat, smoke
or flames, and their nests may be destroyed. More
mobile species tend to fare better, though some
terrestrial species take refuge in wet areas, burrows
and logs.
Other birds, including some raptors,
insectivores and seed-eaters, are attracted to fire
and its charred results, moving in from adjacent
habitats or drawn from far and wide by the
smoke. This is particularly so in the north, where
Black and Brown Falcons, Black and Whistling
Kites, Australian Bustards, woodswallows and
Tree Martins often arrive in large numbers to feed
on flushed, killed or injured animals. Granivores,
including Gouldian Finches, exploit seeds exposed
by the fire. After a relatively short time they move
on, sometimes to the next fire. By contrast, in
temperate areas a more successional colonisation of
the burnt areas occurs and the initial post-fire scene
is often one with few birds.
5
Maintaining fire-free habitat
fragments: Helmeted Honeyeater
A number of colonies of the critically
endangered Helmeted Honeyeater (west
Gippsland subspecies, also known as the
Yellow-tufted Honeyeater) were destroyed
by the Ash Wednesday fires—for example,
those at Cardinia and Cockatoo Creeks. Thus,
the remaining colonies, in streamside lowland
swamp forest at Yellingbo, are maintained
as essentially fire-free, although the Ranger
has trialled small-scale burning to control the
introduced grass Phalaris.
BRUCE QUIN, Department of Sustainability
and Environment, Victoria
The first year
‘In the first year after the fire, the avifauna of burnt
habitats differs from that which develops later, or
which was present before the burn.’
John Woinarski & Harry Recher (1997)
The reduction of food and cover for some resident
bird species leads to starvation, predation or
emigration. Species suited to more open habitats,
mainly seed-eaters and insectivores, may move in
temporarily, from adjacent areas or further afield,
to take advantage of a flush of insects and seeds
generated by the quickly responding growth of
grasses and flowering annuals. Examples include:
Straw-necked Ibis; Torresian Crow; butcherbirds;
Red-tailed Black-Cockatoo; Galah; quail; nightjars;
Red-backed Kingfisher; Partridge Pigeon and
several finch species in the north; Scarlet and Flame
Robins; and Buff-rumped Thornbills in the south.
These species move on or their numbers thin out as
regeneration progresses.
Cumulative impacts:
the Black-eared Miner
The Black-eared Miner numbers less than
450 breeding individuals. Its habitat is mallee
that has been unburnt for 20 or more years,
where it reaches highest densities 40 or more
years since burning. Much of its former habitat
in the Murray Mallee has been cleared for
agriculture. Yellow-throated Miners have
colonised man-made clearings within intact
mallee and are interbreeding with the
Black-eared Miners, swamping most
populations except at Bookmark Biosphere
Reserve. Hybridisation and fire are now the
major threats to the species’ survival.
MICHAEL CLARKE,
La Trobe University, Victoria
Later years
‘The pattern and rate of change in species
abundance following fire differs according to
habitat, floristics, fire history, climate, patch size
and isolation and patchiness of the fire.’
John Woinarski & Harry Recher (1997)
The land area of Australia burned in the last five
years. Map prepared by Cameron Yates and Brian
Lynch (NT Department of Infrastructure Planning
and Environment), from information supplied by
WA DOLA.
As regeneration proceeds, species present
before the fire begin to return or build up; most
populations recover within three to ten years, while
a few take decades to return to pre-fire levels.
Periods of low rainfall may slow the recovery of
vegetation and return of birds. In habitats typically
slow to regenerate, such as old-growth forest, their
characteristic species—e.g. hollow tree nesters
and canopy feeders—may still be absent or less
abundant 50 years after an intense fire that kills
canopy trees.
FIRE SEASONS
Fires in the mallee can create flushes of food
for the Malleefowl, but it needs long-unburnt
country to breed. Photo by Lynn Pedler
DARWIN
TENNANT CREEK
PORT HEADLAND
MT ISA
ALICE SPRINGS
Tarawi Nature Reserve fire management plan
BRISBANE
GERALDTON
KALGOORLIE
PERTH
SYDNEY
CANBERRA
ADELAIDE
MELBOURNE
Winter and spring
Spring
Summer
Spring and summer
Summer and autumn
HOBART
The timing of the main fire seasons reflects the
different weather patterns. Note the tendency for
summer/autumn to be the danger period in the
southern States, and winter/spring in the north.
Source: www.bom.gov.au
Tarawi Nature Reserve is in the semi-arid mallee of New South Wales. The key elements of the Reserve’s
fire management plan put into practice much of the new knowledge in conservation science.
General conservation goal: to manage fire to minimise the risk of any native species becoming extinct.
Objectives:
• ensure consecutive fires are at least 20 years apart in any one area;
• ensure a range of post-fire ages are present in the reserve (at least 50% of each mallee community
should be >40 years old) to promote patchiness in wildfires, although a scale of patchiness is not
specified due to lack of knowledge;
• determine the biodiversity values of long-unburnt mallee (>70 yrs);
• burn strategically to contain the spread of wildfires that may violate the thresholds for fire
frequency, post-fire age diversity or patchiness requirements.
Extracted from Keith et al. (2002)
4
Fire and Birds
Fire and Birds
Responses of birds to a single
fire event
The effects of a fire on bird communities can be
difficult to predict. They vary with fire intensity,
season and extent; the characteristics of the site,
climatic variation before and after; and time
elapsed since fire. Species differ in their response
to fire and individual species vary in their response.
In general, the Australian bush and its wildlife
can cope with single fire events, but over time
frequent, widespread fires change the character of
the landscape and its inhabitants, to the detriment
of fire-sensitive species.
Before, during and after
Flame Robin. Photo by Peter Merritt
Large logs can act as micro fire-breaks, adding
desirable heterogeneity to the habitat, and they
offer refugia for animals in their moist interior.
Regrowth in the early succession stages after fires,
particularly in the south of the country (here Tiajara,
NSW), attracts small insect-eaters such as Scarlet and
Flame Robins. Photo by Graeme Chapman
Some definitions
Backburning: a fire that is intentionally lit to
consume fuel in the path of a wildfire.
Bushfire or wildfire: a general term used to
describe a fire in native vegetation.
Prescribed, controlled, fuel reduction,
or planned burning: a fire lit under specified
(i.e. relatively safe) environmental and
weather conditions to burn over a
predetermined area, at a time, intensity
and rate of spread necessary to achieve
particular management objectives.
Fire-break: any natural or constructed discontinuity in fuel used to break up, stop or
control the spread of a fire.
Fire age: the time elapsed since the last fire.
Fire intensity: the amount of energy released
per unit length of the fire front, usually
expressed as kilowatts (kW) per metre.
Fire regime: the history of fire in a particular
area, comprising the frequency, intensity,
season of burning (i.e. the time of year a
fire occurs) and the type.
Type: refers to whether the fire is above-ground
or below-ground (i.e. a peat fire), but as
almost all fires in Australia are aboveground this component is usually irrelevant.
Fire succession: the series of stages that
vegetation goes through in its recovery
post-fire.
Fuel load: the amount of combustible material,
especially easily ignitable material.
Hazard reduction burn: a fire intentionally lit to
reduce the amount of fuel, and consequently
reduce the risk posed by wildfires. Fuel is any
material, such as bark, leaf litter and living
vegetation, which will burn.
Trittering: mowing and mulching which
involves pulverising the leaf litter so that it
becomes compacted and burns more slowly
with a reduced flame height.
Adapted from the NSW National Parks & Wildlife
Service Fire Management Manual (2001)
policy and management (see ‘Bushfire
management in the Northern Territory’
p. 16, ‘Tarawi Nature Reserve’ p. 5).
Recent legislation in most Australian States
and Territories not only requires that fire
is managed by land managers in fire-prone
vegetation, but that it is used in ecologically sustainable ways. The importance of
periodic prescribed fire (controlled burns)
to increase or maintain biodiversity is now
widely accepted.
Insights from Indigenous experience
can help inform the development of
effective fire management practices. Sadly,
much of this knowledge has been lost or
eroded. More importantly, landscapes are
now substantially modified from those
managed by Indigenous Australians—by
weed invasion, introduced grasses, grazing,
clearing and drainage; and reduced,
fragmented habitats. These factors
can dramatically alter fire impacts on
landscapes and ecosystems.
‘I am confident that the indiscriminate
burning of bush, which is the concomitant of
all farming and grazing operations, is by a
long way the major cause of the disappearance
of many of our rarer birds.’
Edwin Ashby (1924)
The environmental impacts of fire on
natural ecosystems are not well understood
due to the complexity of the problem,
paucity of research, and megadiversity of
the Australian landscape. There are few
detailed long-term studies of the effects
of fire on avian communities, but there
is sufficient information on fire effects
from a broad cross-section of Australian
habitats to identify patterns of response
to individual fires (see ‘Responses of birds
to fire’ p. 5) and predict likely long-term
effects. Depending on the severity of the
fire, the amount of vegetation burned and
killed, and the weather during the recovery
period, most avian communities recover
rapidly following single fires regardless of fire
intensity. However, even single fires may pose
a significant threat to species with restricted
distribution, limited reproductive potential,
poor dispersal ability and/or narrow habitat
requirements. Birds persisting in fragmented
habitats are particularly at risk because the
whole fragment can burn and, post-fire, small
fragments may not be recolonised by all of
their original species.
Nonetheless, far more threatening
across a broad range of avian communities,
are increases in fire frequency and extent,
on the one hand, and fire exclusion on
the other. These tend to homogenise the
landscape, and offer fewer options for
survival and recolonisation.
Detrimental fire regimes have
contributed to the extinction of two
of the three bird species, and three
of the four subspecies, lost since
European colonisation. Inappropriate
fire management is now a factor in the
threatened status of over 50 nationally
recognised threatened bird species (see table
p. 6). Of those threatened species whose
relationships with fire have been welldocumented, almost all show a preference
for less frequent, less extensive fires than
have occurred in recent decades.
Though the task is daunting, the
costs of inaction are great. Fire can be an
economical way to manage large tracts
of land, on a fine scale, with benefits
to biodiversity and human needs. The
challenge will be to identify and develop
the appropriate fire regimes to maintain
fire-dependent habitats and protect the
fewer fire-sensitive habitats. The single
greatest need for land managers incorporating fire into their management is a
useful tool to determine appropriate fire
regimes (see ‘To burn or not to burn’ and
‘Towards a set of biodiversity-friendly fire
management principles’ p. 6).
‘There was a sound as of thunder, mingled with
the crashes of trees and the wild cries of legions of
birds of all kinds; which fell scorched and blackened
and dead to the ground.’
W. Howitt (1856) describing the
1851 Victorian bushfires
The immediate response to fire by birds depends on
the extent, speed and intensity of the fire; habitat;
and species of bird. It is likely that many birds take
action well in advance, and depart or seek shelter.
Some birds are overcome by the heat, smoke
or flames, and their nests may be destroyed. More
mobile species tend to fare better, though some
terrestrial species take refuge in wet areas, burrows
and logs.
Other birds, including some raptors,
insectivores and seed-eaters, are attracted to fire
and its charred results, moving in from adjacent
habitats or drawn from far and wide by the
smoke. This is particularly so in the north, where
Black and Brown Falcons, Black and Whistling
Kites, Australian Bustards, woodswallows and
Tree Martins often arrive in large numbers to feed
on flushed, killed or injured animals. Granivores,
including Gouldian Finches, exploit seeds exposed
by the fire. After a relatively short time they move
on, sometimes to the next fire. By contrast, in
temperate areas a more successional colonisation of
the burnt areas occurs and the initial post-fire scene
is often one with few birds.
5
Maintaining fire-free habitat
fragments: Helmeted Honeyeater
A number of colonies of the critically
endangered Helmeted Honeyeater (west
Gippsland subspecies, also known as the
Yellow-tufted Honeyeater) were destroyed
by the Ash Wednesday fires—for example,
those at Cardinia and Cockatoo Creeks. Thus,
the remaining colonies, in streamside lowland
swamp forest at Yellingbo, are maintained
as essentially fire-free, although the Ranger
has trialled small-scale burning to control the
introduced grass Phalaris.
BRUCE QUIN, Department of Sustainability
and Environment, Victoria
The first year
‘In the first year after the fire, the avifauna of burnt
habitats differs from that which develops later, or
which was present before the burn.’
John Woinarski & Harry Recher (1997)
The reduction of food and cover for some resident
bird species leads to starvation, predation or
emigration. Species suited to more open habitats,
mainly seed-eaters and insectivores, may move in
temporarily, from adjacent areas or further afield,
to take advantage of a flush of insects and seeds
generated by the quickly responding growth of
grasses and flowering annuals. Examples include:
Straw-necked Ibis; Torresian Crow; butcherbirds;
Red-tailed Black-Cockatoo; Galah; quail; nightjars;
Red-backed Kingfisher; Partridge Pigeon and
several finch species in the north; Scarlet and Flame
Robins; and Buff-rumped Thornbills in the south.
These species move on or their numbers thin out as
regeneration progresses.
Cumulative impacts:
the Black-eared Miner
The Black-eared Miner numbers less than
450 breeding individuals. Its habitat is mallee
that has been unburnt for 20 or more years,
where it reaches highest densities 40 or more
years since burning. Much of its former habitat
in the Murray Mallee has been cleared for
agriculture. Yellow-throated Miners have
colonised man-made clearings within intact
mallee and are interbreeding with the
Black-eared Miners, swamping most
populations except at Bookmark Biosphere
Reserve. Hybridisation and fire are now the
major threats to the species’ survival.
MICHAEL CLARKE,
La Trobe University, Victoria
Later years
‘The pattern and rate of change in species
abundance following fire differs according to
habitat, floristics, fire history, climate, patch size
and isolation and patchiness of the fire.’
John Woinarski & Harry Recher (1997)
The land area of Australia burned in the last five
years. Map prepared by Cameron Yates and Brian
Lynch (NT Department of Infrastructure Planning
and Environment), from information supplied by
WA DOLA.
As regeneration proceeds, species present
before the fire begin to return or build up; most
populations recover within three to ten years, while
a few take decades to return to pre-fire levels.
Periods of low rainfall may slow the recovery of
vegetation and return of birds. In habitats typically
slow to regenerate, such as old-growth forest, their
characteristic species—e.g. hollow tree nesters
and canopy feeders—may still be absent or less
abundant 50 years after an intense fire that kills
canopy trees.
FIRE SEASONS
Fires in the mallee can create flushes of food
for the Malleefowl, but it needs long-unburnt
country to breed. Photo by Lynn Pedler
DARWIN
TENNANT CREEK
PORT HEADLAND
MT ISA
ALICE SPRINGS
Tarawi Nature Reserve fire management plan
BRISBANE
GERALDTON
KALGOORLIE
PERTH
SYDNEY
CANBERRA
ADELAIDE
MELBOURNE
Winter and spring
Spring
Summer
Spring and summer
Summer and autumn
HOBART
The timing of the main fire seasons reflects the
different weather patterns. Note the tendency for
summer/autumn to be the danger period in the
southern States, and winter/spring in the north.
Source: www.bom.gov.au
Tarawi Nature Reserve is in the semi-arid mallee of New South Wales. The key elements of the Reserve’s
fire management plan put into practice much of the new knowledge in conservation science.
General conservation goal: to manage fire to minimise the risk of any native species becoming extinct.
Objectives:
• ensure consecutive fires are at least 20 years apart in any one area;
• ensure a range of post-fire ages are present in the reserve (at least 50% of each mallee community
should be >40 years old) to promote patchiness in wildfires, although a scale of patchiness is not
specified due to lack of knowledge;
• determine the biodiversity values of long-unburnt mallee (>70 yrs);
• burn strategically to contain the spread of wildfires that may violate the thresholds for fire
frequency, post-fire age diversity or patchiness requirements.
Extracted from Keith et al. (2002)
6
Fire and Birds
Fire and Birds
Towards a set of biodiversity-friendly fire management principles
South-eastern Red-tailed
Black-Cockatoos and Fire
The endangered South-eastern Red-tailed BlackCockatoo is a dietary specialist; it eats only the
seeds of three tree species—Brown Stringybark,
Desert Stringybark and Buloke. Supplies of these
seeds are patchy in space and time, and flocks tend
to concentrate on the seed stocks that can be most
efficiently harvested. There is mounting evidence
that cockatoo breeding success is related to the
availability of fresh stringybark seed crops.
The stringybark forests of south-western
Victoria are highly flammable and the heathy
understorey requires fire to maintain its floristic
diversity. However, fires that burn or scorch the
canopy result in reduced seed production for up to
nine years. Therefore, the widespread burning of
stringybark forests through the twentieth century
may have been a cause of population decline in
the Red-tailed Black-Cockatoo. With this in mind,
a moratorium on burning was imposed in 1989.
However, there are now good ecological and asset
protection reasons for resuming planned burns.
In an attempt to resolve this impasse, the
Department of Sustainability and Environment,
with the support of the recovery team, has
trialled methods of burning the understorey while
minimising canopy scorch. This is a tall order in
stringybark forests, where the fibrous bark tends
to carry flames upwards. However, given the right
conditions of fuel moisture and weather, the trials
are suggesting that ecological burning aims, or asset
protection aims, can be met whilst minimising the
impact on future crops of stringybark seed.
PETER MENKHORST AND JIM MCGUIRE, Department
of Sustainability and Environment, Victoria
Australia is a large and diverse country, hence
there are many views and requirements for
biodiversity-friendly fire management. The
following are some of several recommendations
in the literature:
• Encourage precautionary fire management.
• Be aware that fire regimes need to be local and
focus on particular objectives.
• Wherever possible develop guidelines and
prescriptions for landscapes and biological
communities, not individual plants and
animals.
• However, where there are species or groups of
species that are susceptible to decline under
certain fire regimes, fire management regimes
should be framed around their needs.
• Aim for fire management targets that are
ranges rather than optima; for example, rather
than choosing the best time for one species
pick a range of times and fire intervals that
cover several species.
• Avoid fire regimes known or suspected to result
in loss of biodiversity in the same or related
ecosystems.
• Be aware that fire frequency is a key element of
fire management—with few exceptions both
fire exclusion and short intervals between fires
over a broad area are damaging to biodiversity.
• Similarly, broadscale, intense fires are
damaging to heterogeneity of habitats
•
•
•
•
•
•
•
•
across the landscape, and hence to
biodiversity values.
Hence, aim to reduce the extent of land/
proportion of vegetation community burned
in single-fire events, no matter what time of
year that happens.
Use fire at a small scale to promote spatial
and temporal variability in fire regimes across
the landscape, that is, a patchwork of areas of
different fire-ages and histories.
Understand that fire-generated patchiness
is good but must be at the right scale (for
example, in relation to the species being
managed or the size of the remnant).
Develop prescriptions to limit the extent and
spatial invariability of fires by controlling fire
behaviour, rather than by imposing artificial
exclusion zones and intervals between fires.
Accept that there will always be gaps in
knowledge, which introduce an element of
uncertainty in the decision-making process.
Allow for unplanned fires.
Climate change means that the country is
likely to be entering a period of hotter, drier
conditions, which will produce more extreme
fire events, which will need to be factored
into management.
Apply adaptive management, including
monitoring, to inform decisions and
improve management.
Threatened birds and fire regimes. This table presents some simple rules for bird-friendly fire management1.
Local conditions and threatened species should be used as a finer guide to management.
To burn or not to burn
Fire regimes result from complex interplay
between biotic (e.g. fuel loads) and abiotic factors
(e.g. weather conditions), increasingly overlaid
with human decisions in support of a variety of
land uses, including biodiversity conservation.
Land managers must weigh up these factors to
estimate the threat from uncontrolled fire and the
desirability of a controlled burn.
contours
slope
fire history
vegetation
land cover
fuel loadings
McArthur
Fire Model
Main
habitat
Threatened species for which
inappropriate fire management is a threat2
Current general fire problem
for bird conservation
Fire management for bird
conservation
Coastal and
sub-coastal
shrublands
Orange-bellied Parrot CE
Ground Parrot (eastern) V
Ground Parrot (western) CE
Rufous Scrub-bird (northern) V
Noisy Scrub-bird V
Southern Emu-wren (Fleurieu Peninsula) CE
Southern Emu-wren (Eyre Peninsula) V
Eastern Bristlebird (northern) CE
Eastern Bristlebird (southern) E
Western Bristlebird V
Rufous Bristlebird (Otways) V
Western Whipbird (western heath) V
Too frequent burning;
too coarse a mosaic.
Pattern: Fine mosaic of areas of
different fire-ages with a bias towards
retention of older fire ages.
Intensity: Low.
Mallee
Malleefowl V
Mallee Emu-wren V
Black-eared Miner E
Western Whipbird (eastern) E
Fire management (prescribed
burns or Aboriginal burning
regimes) has been much
reduced so that wildfires are
too hot and extensive.
Pattern: Mosaic of areas of different
fire-ages with a bias towards
retention of older fire ages. Fire
frequency at most every 40 years in
any particular area.
Intensity: Low.
Temperate
eucalypt
open forests
Red-tailed Black-Cockatoo (south-eastern) E
Glossy Black-Cockatoo (Kangaroo Island) E
Helmeted Honeyeater CE [riparian]
Forty-spotted Pardalote E
Fire exclusion.
Pattern: Mosaic of fire-ages across
the landscape with a bias towards
retention of older fire ages.
Intensity: Flexible use of a broad
range of fire regimes.
Tropical and
sub-tropical
forests/
rainforest
Southern Cassowary V
Red Goshawk V
Black-breasted Button-quail V
Masked Owl (Tiwi Islands) E
Fire exclusion permits spread
of fire-sensitive species.
Pattern: Mosaic of fire-ages across
the landscape with a bias towards
retention of older fire ages.
Intensity: Occasional hot burns.
Tropical and
sub-tropical
savanna
woodlands
and
grasslands
Buff-breasted Button-quail E
Partridge Pigeon (western) V
Golden-shouldered Parrot E
Paradise Parrot Ex
Night Parrot CE
Hooded Robin (Tiwi Island) V
Crested Shrike-tit (northern) E
Gouldian Finch E
Star Finch (Cape York) E
Fires now too hot, extensive
and frequent, or, alternatively, too infrequent.
Pattern: Fine-scale mosaic of
fire-ages across the landscape,
with between 10 and 30% of
landscape burned each year.
Intensity: Occasional hot burns.
Wetlands
Australian Bittern (Australasian) V
Burning of habitat to create
pasture.
No prescribed burns.
standard fuel &
weather conditions
Hazard
structures
roads and trails
residential
Risk
revegetation
residential
structures
constructed
values
fauna values
flora values
natural
values
Risk/Hazard
matrix
Values
Threat
One approach to the prediction of the threat of fire.
Source http://www.planning.sa.gov.au
1Based
on information in Woinarski (1999) www.deh.gov.au/biodiversity/publications/technical/fire/
from Garnett & Crowley (2002). Categories of threat in decreasing order of severity: Ex = Extinct;
CE = Critically Endangered; E = Endangered; V = Vulnerable; subspecies name in brackets. Twenty-two other species
are listed as Near Threatened, and inappropriate fire regimes are among their major threats.
2Extracted
7
LIVING WITH FIRE—BIRDS
IN NORTHERN AUSTRALIA
Australia’s north is a landscape of fire, and some naive
ideal of fire suppression and exclusion will neither
work nor suit most bird species
by John Woinarski
Climatic conditions, vegetation, social factors and human population
dispersion cause fire to be a very different phenomenon in northern
Australia to that elsewhere in the continent. The north is monsoonal,
with a strongly seasonal climate marked by a long, almost rainless,
warm dry season (typically from about April to October), and a strongly
contrasting hot wet season.
Fire is an inevitable part of this landscape. The dense, tall grasses grow
rapidly over the short wet season, and then dry out over the long dry season,
becoming highly flammable. Without human intervention, this vegetation
burns readily with ignition from lightning strikes, a characteristic feature of
the first thunderstorms that mark the transition from the dry to the wet.
Humans have long been moulding this landscape. For the Indigenous
people fire has been a crucial part of life and their main management tool
for 40,000 years or more. Such application of fire was far from reckless.
The consequences of ill-advised fire management were severe: vital food
sources could be eliminated through inappropriate fires, and fires that
spread to burn neighbouring clan estates could invite retribution. In parts
of northern Australia this tradition continues. In these areas, the application
of fire may be a highly skilled and carefully considered operation, carried
out diligently throughout the year. Typically, this traditional management
involves many small ‘cool’ fires, producing an intricate network: a fine-scale
mosaic of unburnt patches and patches burned at different times through
the year. Often, the more fire-sensitive components of the landscape—such
as rainforest patches—were explicitly and deliberately protected from fire,
typically by burning around their margins. These elements were valued
because they produced important foods, particularly yams, in traditional
diets; and the maintenance of such fire-sensitive elements in a clan estate
was a sign of proper management.
Over the last century, traditional Indigenous fire management in
most of northern Australia has broken down. Indigenous people were
dispossessed from much of the landscape. Even in lands that maintained
Indigenous ownership, population dispersion and lifestyles changed. In the
decades around the Second World War, most of the population moved off
their clan estates to live at mission stations and other townships. In some
areas, this dynamic has been reversed through the ‘outstation movement’,
beginning in the 1970s. But, over most of northern Australia, traditional
burning has been disrupted and replaced by very different fire regimes.
Below left: With less than 50 known individuals the Eastern Bristlebird (northern
subspecies), of Cooloola National Park and the Conondale Ranges, Queensland,
is critically endangered. Its main threat is changed fire regimes, with fire now too
frequent, destroying the species’ tussock grass habitat, or too infrequent, allowing
shrubs to become too dense. Below: Fires remove dense ground cover to expose
seeds on which the finches feed, but may also destroy wet season food species,
and nests. Here a Masked Finch collects charcoal for its nest (presumed to help
keep the nest dry and sanitised). Photos by Graeme Chapman
Wildfire at Kakadu National Park, Northern Territory. Photo by Raoul Slater
Fuelling fire
The current fire regimes vary somewhat between tenures. On pastoral
lands, which occupy about half of northern Australia, fire is generally
unwanted and suppressed—livestock consume most of the grassy fuels,
so that fire behaviours and intensities are now different to those that
prevailed over tens of thousands of years. Partly because of the reduced
incidence of fires, vegetation in many pastoral areas is changing, often
with increases in the density and extent of woody shrubs and decrease in
grassland areas (‘vegetation thickening’). Fires on other tenures are now
characterised by an increased incidence of late dry season burns, and these
are typically more intense and extensive. The previous fine mosaic of
patchy burnt and unburnt areas has been replaced by broad-scale conflagrations that homogenise the landscape. Far more often than previously,
these fires engulf the fire-sensitive elements of the landscape.
Superimposed on this change in fire regimes is the consequence of
the increasing and largely uncontrollable spread of African and South
American pasture grasses, deliberately introduced by pastoralists and
pasture scientists to transform (‘improve’) the landscape. This insidious
set is marked by their ability to dominate almost every environment in
northern Australia, including wetlands (Para Grass, Olive Hymenachne),
tropical open forests and savanna woodlands (Gamba Grass, Mission
Grass, Guinea Grass) and semi-arid woodlands (Buffel Grass). The
replacement of native understoreys by introduced pastures is itself an
ecological wound but, worse, these grasses also greatly alter fire regimes.
Largely because they are voracious consumers of soil nutrients, exotic
grasses produce fuel loads that are far greater than native grasses (up to
seven times the biomass), and they typically cure later in the dry season.
This inevitably means that fires fuelled by exotic, invasive pastures
are more intense (up to 10 times hotter) than fires with native grass
understoreys. Whereas previously fires in northern Australia burned the
grassy understorey and rarely affected the tree layer, exotic grasses are now
fuelling crown fires that kill the tree layer.
Currently, fires burn about 30–50% of northern Australia each year.
Many areas have been burnt every year over the last decade. The scale and
recurrence of fires is vastly different to southern Australia. In extent, the
regular fires of northern Australia dwarf the bushfires in south-eastern
Australia, such as Ash Wednesday and those in the south-east highcountry in 2003. For example, in five days of October 2004, a fire in
the Sturt Plateau and northern Tanami Desert of the Northern Territory
burned out an area greater in size than Tasmania, but didn’t even make
headlines in the local newspapers.