Future fire scenarios: Predicting the effect of fire management strategies on the trajectory of high-quality habitat for threatened species

Abstract

Prescribed (or “planned”) burning is used by land managers to reduce fuel-loads in order to mitigate the spread of wildfire, thereby protecting life and property, and to promote environmental heterogeneity to enhance biodiversity. Globally, many fire management agencies focus on increasing extent and frequency of prescribed burning. There is a need to assess how high levels of prescribed burning may affect the long-term, landscape-level persistence of ecological communities. We forward projected management scenarios over 21 years to explore how the operationally realistic implementation of four different prescribed burn targets, covering 5, 3, 1.5 and 0% of a large reserve per annum (p.a.) might affect provision and removal of fire-mediated habitat of 11 rare and threatened bird species. Sustained implementation of high targets (5 and 3% p.a.) homogenised the landscape toward young vegetation, substantially reducing highly suitable habitat for species requiring intermediate (20–60 years post-fire) and older (60+ years) age classes. In contrast, no prescribed burning generated insufficient habitat for species with early (<20 years) and intermediate seral requirements. Strategies reliant upon persistently high levels of prescribed burning are likely to have negative effects on a number of threatened species already considered vulnerable due to their low populations and restricted ranges. In contrast, management processes that allow for periodic evaluation and flexibility in how strategies are implemented would better enable practitioners to tailor fire management to individual ecosystems. Carefully targeting key areas for wildfire prevention, and promoting some successional changes through application of fire in other areas, will help to maintain and improve suitable habitat for species of conservation concern.