Peter Smith, Judy Smith
Australian Journal of Zoology 64 (5), 312-326, (17 January 2017) https://doi.org/10.1071/ZO16053
KEYWORDS: bird species richness, climate change, Fire frequency, Fire severity, nectarivorous birds, Time since fire
We investigated bird habitat relationships in extensive eucalypt forest in the Blue Mountains, New South Wales, in 1986–87, assessing the importance of fire regime variables compared with other habitat variables. Our study sites encompassed a wide range of postfire ages, fire frequencies and fire severity, but we found no major bird community differences corresponding to differences in fire regime. The more common forest bird species appeared well adapted to fire regime variation in the 1980s. Tree canopy height was a far greater influence, with more species and more birds in taller forests (interpreted as a result of higher soil fertility leading to higher productivity of bird foods and greater structural complexity in taller forests). Other trends were fewer birds where there was a rainforest understorey under the eucalypts (reflecting the general scarcity of rainforest birds in the Blue Mountains), and more birds where nectar-rich flowers were more abundant (reflecting the abundance of nectarivorous birds in the Blue Mountains, especially over winter). The climate has changed since the 1980s and fires threaten to become much more severe, extensive and frequent. How these changes will impact on forest birds, and what management responses are required, is a critical area for further study.