Rufous Scrub-bird 'Atrichornis rufescens' monitoring at the extremities of the species' range in New South Wales (2010-2012)

The status of the Rufous Scrub-bird 'Atrichornis rufescens' was monitored between 2010 and 2012 using volunteers at Gloucester Tops and the Border Ranges National Park, high-altitude locations at the extremity of the species' range in New South Wales. Transects were walked to determine the densities of calling territorial males, allowing comparison with similar studies 30 years earlier. Both locations have been nominated as Important Bird Areas, based on their importance to the remnant populations of the Scrub-bird. Gloucester Tops is the southern extremity of the range of the subspecies 'A. r. ferrieri', where there was evidence of a slight increase in abundance and clustering of territories. This is consistent with the possibility of population retreat to high-altitude remnant montane habitat. In contrast, in the Border Ranges, territory densities of the subspecies 'A. r. rufescens' were slightly lower than at Gloucester Tops, and may have declined slightly compared with the earlier study. Both areas are in passively managed National Parks, but Rufous Scrub-birds are found in different vegetation types: eucalypt forest at Gloucester Tops and rainforest in the Border Ranges. At both these locations, there was a 30-35% decrease in the detection of Scrub-bird territories in 2012 compared with the previous 2 years. This is attributed to dry conditions during August-November, entering and during the Scrub-bird's breeding season. Ongoing monitoring is essential to determine whether this decrease is temporary, because the birds were calling less, or permanent.