Pyrodiversity promotes avian diversity over the decade following forest fire

Abstract

An emerging hypothesis in fire ecology is that pyrodiversity increases species diversity. We test whether pyrodiversity-defined as the standard deviation of fire severity-increases avian biodiversity at two spatial scales, and whether and how this relationship may change in the decade following fire. We use a dynamic Bayesian community model applied to a multi-year dataset of bird surveys at 1106 points sampled across 97 fires in montane California. Our results provide strong support for a positive relationship between pyrodiversity and bird diversity. This relationship interacts with time since fire, with pyrodiversity having a greater effect on biodiversity at 10 years post-fire than at 1 year post-fire. Immediately after fires, patches of differing burn severities hold similar bird communities, but over the ensuing decade, bird assemblages within patches of contrasting severities differentiate. When evaluated at the scale of individual fires, fires with a greater heterogeneity of burn severities hold substantially more species. High spatial heterogeneity in severity, sometimes called 'mixed-severity fire', is a natural part of wildfire regimes in western North America, but may be jeopardized by climate change and a legacy of fire suppression. Forest management that encourages mixed-severity fire may be critical for sustaining biodiversity across fire-prone landscapes.

An experimental test of whether pyrodiversity promotes mammal diversity in a northern Australian savanna

“…While our results concur with those of Maravalhas and Vasconcelos (), who demonstrated the importance of pyrodiversity for ant diversity in Brazilian cerrado (savanna), they contrast with research of Australian and African savanna invertebrates, which exhibited a high level of resilience to fire (Andersen et al., ; Parr, Robertson, Biggs, & Chown, ). Again, while our results concur with some studies linking pyrodiversity to the diversity of faunal groups in biomes other than savanna (Ponisio et al., ; Tingley et al., ), they contrast with others (Farnsworth et al., ; Taylor et al., ). The inconsistent support for the pyrodiversity hypothesis between biomes and faunal groups emphasises the proposition of Kelly and Brotons () of the need for fire management to be tailored to local conditions.…”

“…This uncertainty has recently stimulated critical analyses of the relationship between pyrodiversity and biodiversity (Kelly, Brotons, & Mccarthy, ; Parr & Andersen, ; Taylor et al., ). For example, while Tingley, Ruiz‐Gutiérrez, Wilkerson, Howell, and Siegel () demonstrated that pyrodiversity promotes bird diversity in Californian conifer forests, Taylor et al. () found no such pattern in a semi‐arid region of south‐eastern Australia, and suggested that burning for fire‐mediated heterogeneity could actually threaten the avian fauna in this system.…”

Age‐dependent habitat relationships of a burned forest specialist emphasise the role of pyrodiversity in fire management

“…Wildfire is a key ecological disturbance in forests world‐wide, generating successional mosaics of habitat that structure biotic communities (Kelly & Brotons, ). Variation in fire regime characteristics—termed pyrodiversity—creates heterogeneous post‐fire habitat, which has been correlated with increased biodiversity in a variety of fire‐prone systems (Beale et al., ; Tingley, Ruiz‐Gutiérrez, Wilkerson, Howell, & Siegel, ). Mounting evidence in support of this ‘pyrodiversity–biodiversity’ hypothesis has made promoting and retaining fire heterogeneity an increasingly influential guiding principal in forest management and biodiversity conservation (Kelly, Brotons, & McCarthy, ).…”

Ecology and Conservation of a New Carnivorous Marsupial Species: the Silver-Headed Antechinus (Antechinus argentus)

“…A landmark study by Martin and Sapsis (1992) hypothesised that temporal and spatial variation in fires can promote biodiversity by creating a wider variety of ecological niches available for species. A growing body of literature has supported this hypothesis (see Hutto et al, 2016, Ponisio et al, 2016, Tingley et al, 2016. However, pyrodiversity doesn't always promote biodiversity.…”

“…The interactions between fire and biodiversity are complex (Gill et al, 2013, Tingley et al, 2016. Many plants and animals require fire to survive, but even in fire-prone habitats some species are highly sensitive to fire .…”