A review of eucalypt dieback associated with bell miner habitat in south-eastern Australia.

Abstract

We aim to assess current knowledge, and identify gaps in knowledge concerning bell-miner-associated dieback (BMAD) in south-eastern Australia. We review BMAD as a form of forest dieback, and bell miner and psyllid interrelations. We then consider indirect and direct causal factors associated with local functional scales (tree crown), and finally, indirect and direct causal factors associated with broader functional scales (forest stand and landscape processes). This paper emphasises publishedliterature and is a summary of a more detailed report prepared for the BMAD working group which explicitly included personal communications with many researchers, managers and membersof conservation groups and the timber industry. We conclude that BMAD is a significant threat to the sustainability of the moist eucalypt forests of north-eastern NSW and south-eastern Queensland, and to biodiversity conservation at a national scale. There are serious deficiencies in the information base for most BMAD issues. While there are clear interactions between bell miners and psyllids, there are many other, less well quantified interactions that may be of greater significance to the developmentof the problem. We suggest that management and research efforts towards solutions urgently target disturbances that lead to changes in forest canopy structure, but there is unlikely to be a single orsimple management solution. An integrated management program will be necessary as concentration on particular management regimes in isolation is unlikely to resolve the BMAD problem because BMAD is associated with interacting disturbances.