Hot Topic

Managing fire for plant and animal conservation

Friday, 25 November 2016  | 

Variation in the time between fires, their severity, size and patchiness, and the season in which they occur is called ‘pyrodiversity’. Because plants and animals often depend on resources that vary as a result of fire, it is argued that pyrodiversity will produce a diversity of habitats that can support more species. Some studies demonstrate that more plants and animals live in areas with a high diversity of fire histories, while others show no such relationship, challenging the generality of the hypothesis that ‘pyrodiversity promotes biodiversity’.

Relationships between fire and biodiversity are context-specific, and vary between species, ecosystems and across spatial scales. For example, pyrodiversity increases bird diversity in eucalypt forests and plant-pollinator diversity in mixed-conifer forests. By contrast, unqualified application of pyrodiversity could reduce diversity of vertebrates in mallee vegetation, and ants and termites in savannas are relatively resilient to variation in fire regimes.

Ecological heterogeneity is important for biodiversity conservation, but not all forms of fire-driven variation are desirable. The ability to identify consistent relationships between pyrodiversity and biodiversity is complicated by feedbacks with other ecological processes. For example, climate, grazing and predation strongly affect fire and biodiversity, as well as relationships between them.

How can scientists and decision makers use the pyrodiversity concept for biodiversity conservation? Foremost, it is essential to recognise that there is no ‘one-size-fits-all’ approach. Natural ecosystems contain different species, have different fire regimes and present different fire risks to biodiversity and people. Fire management will be more effective when guided by local knowledge and based on the demonstrated requirements of plants and animals, as well as the habitats they depend on.

Supporting Research

Andersen A. N., Ribbons R. R., Pettit M. & Parr C. L. (2014) Burning for biodiversity: highly resilient ant communities respond only to strongly contrasting fire regimes in Australia's seasonal tropics. Journal of Applied Ecology 51, 1406-13.
To examine the sensitivity of tropical savanna ants to variation in fire regimes using results from a long-term fire experiment.
Avitabile S. C., Nimmo D. G., Bennett A. F. & Clarke M. F. (2015) Termites are resistant to the effects of fire at multiple spatial scales. PLOS ONE 10, e0140114.
To examine the distribution and occurrence of termites in the fire-prone, semi-arid mallee region of south-eastern Australia.
Berry L. E., Lindenmayer D. B. & Driscoll D. A. (2015) Large unburnt areas, not small unburnt patches, are needed to conserve avian diversity in fire-prone landscapes. Journal of Applied Ecology 52, 486-95.
To test bird responses to size and isolation of unburnt patches within a large wildfire in southern Australia.
Bird R. B., Tayor N., Codding B. F. & Bird D. W. (2013) Niche construction and Dreaming logic: Aboriginal patch mosaic burning and varanid lizards (Varanus gouldii) in Australia. Proceedings of the Royal Society B: Biological Sciences 280.
To investigate the effects of patch mosaic burning and Martu hunting on sand monitor lizard (Varanus gouldii) population density.
Bowman D. M. J. S., Perry G. L. W., Higgins S. I., Johnson C. N., Fuhlendorf S. D. & Murphy B. P. (2016) Pyrodiversity is the coupling of biodiversity and fire regimes in food webs. Philosophical Transactions of the Royal Society B: Biological Sciences 371.
To develop a novel conceptualisation of pyrodiversity as an emergent property of fire embedded in food webs: (1) considering how this idea relates to the fire regime concept; (2) reviewing the correlative and mechanistic evidence for and against the importance of spatio-temporal fire patterns on biodiversity and how this influences ecological processes; and (3) outlining the implications of our argument for the management of ecosystems.
Bradstock R. A., Bedward M., Gill A. M. & Cohn J. S. (2005) Which mosaic? A landscape ecological approach for evaluating interactions between fire regimes, habitat and animals. Wildlife Research 32, 409-23.
To explore the link between ‘fire mosaics’ and the persistence of animal species. Key questions included: are variegated time since fire (i.e. ‘visible’) mosaics required for species persistence in all types of landscape context?, is the ‘visible’ mosaic the only form of fire/habitat/ landscape heterogeneity that is needed to adequately understand the requirements of animals resident in areas subject to recurrent fire?, and, are the kinds of mosaics required for persistence of animal populations sensitive to practical management constraints?
Burgess E. E. & Maron M. (2016) Does the response of bird assemblages to fire mosaic properties vary among spatial scales and foraging guilds? Landscape Ecology 31, 687-99.
To compare the influence of fire mosaics and environmental heterogeneity on bird assemblages at two spatial scales, to evaluate the influence of spatial scale on heterogeneity/biodiversity relationships.
Clarke M. F. (2008) Catering for the needs of fauna in fire management: science or just wishful thinking? Wildlife Research 35, 385-94.
To examine how well four common premises that appear to underpin current fire management practices in Australia encompass the needs of fauna.
Davies A. B., Eggleton P., van Rensburg B. J. & Parr C. L. (2012) The pyrodiversity–biodiversity hypothesis: a test with savanna termite assemblages. Journal of Applied Ecology 49, 422-30.
To explore how termite diversity varied with mean annual precipitation and whether faunal responses to fire regimes varied with rainfall.
Farnsworth L. M., Nimmo D. G., Kelly L. T., Bennett A. F. & Clarke M. F. (2014) Does pyrodiversity beget alpha, beta or gamma diversity? A case study using reptiles from semi-arid Australia. Diversity and Distributions 20, 663-73.
To assess the hypothesis that pyrodiversity begets biodiversity by enhancing community differentiation (beta diversity), resulting in increased landscape-scale richness (gamma diversity).
Griffiths A. D., Garnett S. T. & Brook B. W. (2015) Fire frequency matters more than fire size: Testing the pyrodiversity–biodiversity paradigm for at-risk small mammals in an Australian tropical savanna. Biological Conservation 186, 337-46.
Evaluate the implications of contrasting patch-mosaic burning scenarios for the population dynamics and risk of decline of four species of small mammals in northern Australia.
Kelly L. T., Bennett A. F., Clarke M. F. & McCarthy M. A. (2015) Optimal fire histories for biodiversity conservation. Conservation Biology 29, 473-81.
To determine the optimal fire history of a given area for biological conservation with a method linking tools from 3 fields of research: species distribution modeling, composite indices of biodiversity, and decision science.
Kelly L. T., Brotons L. & McCarthy M. A. (2016) Putting pyrodiversity to work for animal conservation. Conservation Biology, n/a-n/a.
To provide better guidance on managing ‘pyrodiversity for biodiversity’.
Kelly L. T., Nimmo D. G., Spence-Bailey L. M., Taylor R. S., Watson S. J., Clarke M. F. & Bennett A. F. (2012) Managing fire mosaics for small mammal conservation: a landscape perspective. Journal of Applied Ecology 49, 412-21.
To establish the relative influence of five landscape properties - the proportional extent of fire age-classes, the diversity of fire age-classes, the extent of the dominant vegetation type, rainfall history and biogeographic context – on small mammal populations.
Lawes M. J., Murphy B. P., Fisher A., Woinarski J. C. Z., Edwards A. C. & Russell-Smith J. (2015) Small mammals decline with increasing fire extent in northern Australia: evidence from long-term monitoring in Kakadu National Park. International Journal of Wildland Fire 24, 712-22.
(1) To examine the proposition that small mammals in the tropical savannas of northern Australia are being ‘burnt out’ of the landscape by frequent large-scale fires of low patchiness, because they typically have home ranges much smaller than contemporary fire sizes and cannot easily escape the effects of these large, homogeneous fires. (2) Compare the effect of fire extent, in conjunction with fire frequency, season and spatial heterogeneity (patchiness) of the burnt area, on mammal declines in Kakadu National Park over a recent decadal period.
Maravalhas J. & Vasconcelos H. L. (2014) Revisiting the pyrodiversity–biodiversity hypothesis: long-term fire regimes and the structure of ant communities in a Neotropical savanna hotspot. Journal of Applied Ecology 51, 1661-8.
To evaluate how communities of ants differ with variation in the frequency and seasonal timing of fire in Brazilian Cerrado (savanna), a global biodiversity hotspot.
Martin RE, Sapsis DB. 1992. Fires as agents of biodiversity: pyrodiversity promotes biodiversity. Proceedings of the Symposium on Biodiversity in Northwestern California. Wildland Resources Centre, University of California, Berkeley.
To discuss how changes in North American fire regimes, fire suppression and reductions in pyrodiversity influence biodiversity.
Nimmo D. G., Kelly L. T., Spence-Bailey L. M., Watson S. J., Taylor R. S., Clarke M. F. & Bennett A. F. (2013) Fire Mosaics and Reptile Conservation in a Fire-Prone Region. Conservation Biology 27, 345-53.
To investigate the landscape-level drivers of reptile distributions in a fire-prone, semiarid region of southeastern Australia.
Parr C. L. & Andersen A. N. (2006) Patch mosaic burning for biodiversity conservation: a critique of the pyrodiversity paradigm. Conservation Biology 20, 1610-9.
To (1) provide an overview of patch mosaic burning theory, (2) explore how the theory is being applied in practice, (3) examine the relationship between pyrodiversity and biodiversity, and (4) discuss the way forward for improved patch mosaic burning.
Pastro L. A., Dickman C. R. & Letnic M. (2011) Burning for biodiversity or burning biodiversity? Prescribed burn vs. wildfire impacts on plants, lizards, and mammals. Ecological Applications 21, 3238-53.
To test the effects of wildfire and prescribed burns on alpha and beta diversity of plants, mammals and lizards.
Ponisio L. C., Wilkin K., M'Gonigle L. K., Kulhanek K., Cook L., Thorp R., Griswold T. & Kremen C. (2016) Pyrodiversity begets plant–pollinator community diversity. Global Change Biology 22, 1794-808.
To examine how pyrodiversity, combined with drought intensity, influences plant-pollinator communities.
Sitters H., Christie F. J., Di Stefano J., Swan M., Penman T., Collins P. C. & York A. (2014) Avian responses to the diversity and configuration of fire age classes and vegetation types across a rainfall gradient. Forest Ecology and Management 318, 13-20.
To test relationships between bird diversity and landscape diversity and configuration across a rainfall gradient. Landscape metrics were based on fire-history attributes and vegetation characteristics.
Taylor R. S., Watson S. J., Nimmo D. G., Kelly L. T., Bennett A. F. & Clarke M. F. (2012) Landscape-scale effects of fire on bird assemblages: does pyrodiversity beget biodiversity? Diversity and Distributions 18, 519-29.
To examine the likely impact of two dominant fire-management strategies on the mallee avifauna: 1) the widely held, but rarely tested, assumption that ‘pyrodiversity begets biodiversity’ and 2) an alternative management strategy that greater proportions of older vegetation in the landscape will have a positive effect on species richness and diversity.
Trauernicht C., Brook B. W., Murphy B. P., Williamson G. J. & Bowman D. M. J. S. (2015) Local and global pyrogeographic evidence that indigenous fire management creates pyrodiversity. Ecology and Evolution 5, 1908-18.
(1) To better understand the ecological outcomes of anthropogenic burning using the spatial distribution of Callitris groves in Arnhem Land and Kakadu National Park to examine fine-scale patterns in the availability of long-unburnt habitat; (2) Explore how altering fire size, and therefore the spatial grain of fire occurrence, affects both spatial and temporal aspects of pyrodiversity.
Codding B. F., Bliege Bird R., Kauhanen P. G. & Bird D. W. (2014) Conservation or co-evolution? Intermediate levels of Aboriginal burning and hunting have positive effects on kangaroo populations in Western Australia. Human Ecology 42, 659-69.
To test three predictions to determine the combined effects of Aboriginal burning and hunting on euro (Macropus robustus) populations. Firstly by examining euro distributions across patches of different seral stages to determine if they do indeed prefer particular stages of vegetative regrowth. If this is the case, then more fine-grained mosaics of these different seral stages should provide euros with greater access to preferred resources within their daily foraging range. Secondly, if euros benefit from living within a fine-grained mosaic of alternating seral stages, then their densities should be higher in regions with greater seral-stage diversity and heterogeneity. Finally, because hunting pressure may covary spatially with burning, euro populations may be greatest at intermediate levels of human activity, where the net benefits of Aboriginal burning are high enough to offset any negative impact of Aboriginal hunting.
Enright N. J., Fontaine J. B., Lamont B. B., Miller B. P. & Westcott V. C. (2014) Resistance and resilience to changing climate and fire regime depend on plant functional traits. Journal of Ecology 102, 1572-81.
To quantify the effects of more frequent fire and lower rainfall – as projected to occur under a warming and drying climate – on population responses of shrub species in biodiverse Mediterranean- climate type shrublands near Eneabba, southwestern Australia.
Giljohann K. M., McCarthy M. A., Kelly L. T. & Regan T. J. (2015) Choice of biodiversity index drives optimal fire management decisions. Ecological Applications 25, 264-77.
To investigate the influence the choice of objective function and taxonomic focus has on the optimal fire management recommendations. To evaluated a recent hazard reduction policy to annually burn a fixed amount of the landscape and compare results to the optimal solution.
Penman T. D., Christie F. J., Andersen A. N., Bradstock R. A., Cary G. J., Henderson M. K., Price O., Tran C., Wardle G. M., Williams R. J. & York A. (2011) Prescribed burning: how can it work to conserve the things we value? International Journal of Wildland Fire 20, 721-33.
To address two questions: (1) to what extent can fuel reduction burning reduce the risk of loss of human life and economic assets posed from wildfires? (2) To what extent can prescribed burning be used to reduce the risk of biodiversity loss?
Gill A. M. & McCarthy M. A. (1998) Intervals between prescribed fires in Australia: what intrinsic variation should apply? Biological Conservation 85, 161-9.
To examine various sources of evidence that can be used to determine variation appropriate to the conservation of biodiversity while minimizing the chances of economically destructive fires.
Bradstock R. A. & Kenny B. J. (2003) An application of plant functional types to fire management in a conservation reserve in southeastern Australia. Journal of Vegetation Science 14, 345-54.
To describe the application of the vital attributes scheme of Noble & Slatyer (1980) to fire managementin a conservation reserve in SE Australia containing a diverse array of woody species.
Burrows N. D. (2008) Linking fire ecology and fire management in south-west Australian forest landscapes. Forest Ecology and Management 255, 2394-406.
To describe a range of evidence-based practical fire regimes that can be implemented to conserve biodiversity and toprotect human life and property in south-west Australian forests.
Bradstock R. A., Bedwards M. & Cohn J. S. (2006) The modelled effects of different fire management strategies on the conifer Callitris verrucosa within semi-arid mallee vegetation in Australia. Journal of Applied Ecology 43, 281-292.
To identify a management solution, based on levels and spatial patterns of prescribed fire and unplanned fire, that serves to reduce the size of wildfires while maintaining viable populations of obligate seeder Callitris verrucosa.
Haslem A., Kelly L. T., Nimmo D. G., Watson S. J., Kenny S. A., Taylor R. S., Avitabile S. C., Callister K. E., Spence-Bailey L. M., Clarke M. F. & Bennett A. F. (2011) Habitat or fuel? Implications of long-term, post-fire dynamics for the development of key resources for fauna and fire. Journal of Applied Ecology 48, 247-256
To document temporal change in habitat and fuel attributes over an extended post-fire chronosequence in mallee vegetation.
Keith D. A. & Bradstock R. A. (1994) Fire and competition in Australian heath: a conceptual model and field investigations. Journal of Vegetation Science 5, 347-54.
To describe a conceptual model of heath vegetation, in which species were classified into five functional groups based on characteristics of their propagule pools, post-fire growth, timing and mode of reproduction and competitive status. The model assumes no recruitment without fire and a simple competitive hierarchy based on vertical stature. A critical feature of the model is an initial post-fire window of 5-6 yr in which competition from overstorey species on understorey species is reduced. Understorey functional groups differ in their ability to exploit this window.
Tozer M. G. & Bradstock R. A. (2003) Fire-mediated effects of overstorey on plant species diversity and abundance in an eastern Australian heath. Plant Ecology 164, 213-23.
To: (1) determine if floristic composition in Banksia heath is correlated with the distribution of the shrub overstorey; (2) determine if patterns in floristic composition related to the presence/absence of the shrub overstorey are similar at different points on a moisture (resource) gradient; (3) consider possible mechanisms for overstorey effects and the implications of fire regimes at a variety of spatial scales.