David MJS Bowman (1), Lynda D Prior (2), Brett R Murphy (3), Grant J Williamson (4) and Owen D Bassett (5)
1 School of Biological Sciences, Private Bag 55, University of Tasmania, Hobart Tasmania 7000 david.bowman@utas.edu.au
2 School of Biological Sciences, Private Bag 55, University of Tasmania, Hobart Tasmania 7000 lynda.prior@utas.edu.au
3 Research Institute for the Environment and Livelihoods, Charles Darwin University, Darwin NT 0909, Australia Brett.P.Murphy@cdu.edu.au
4 School of Biological Sciences, Private Bag 55, University of Tasmania, Hobart Tasmania 7000 grant.williamson@utas.edu.au
5 Forest Solutions, 46 Charles Street, Benalla, Victoria 3672, Australia owen@forestsolutions.com.au
We demonstrate how a series of three fires in quick succession caused the population collapse of an obligate-‐seeder forest endemic to the Australian Alps bioregion. Eucalyptus delegatensis is a tall, long-‐lived tree that regenerates following fire disturbance that stimulates the release of seed from an aerial seedbank. If regenerating stands are burnt before they reach sexual maturity (after about 20 years) the species suffers local extinction and can only re-‐establish via gradual colonisation. Aerial and field surveys in a valley was burnt by three fires (2003, 2007 and 2013) in the Alpine National Park, Victoria, demonstrated the complete population collapse of this species. In order to restore this species’ range, park managers aerially sowed seeds by adapting a forestry technique. Surveys revealed that the establishment of sown seeds was satisfactory, and seedlings survived the first summer. The challenge for land managers is to protect these seedlings from wildfires for the next two decades to avoid loss of these artificially regenerated forests. If the trend for more frequent fires continues, a more extreme intervention may be required, involving replacing the obligate-‐seeder species with more fire-‐ and drought-‐tolerant resprouting eucalypts that currently occur at lower elevations. This study demonstrates the capacity of landscape fire to abruptly change species’ distributions, and the need for assisted migration to counteract losses of vulnerable species in the face of rapidly changing fire regimes.