Justification of Red List category
This species has a small population with a restricted area of occupancy and number of locations that is declining as a result of large fires and drought, with the risk of further fires increasing. It is therefore classified as Vulnerable.
Population justification
The population of Red-lored Whistler is difficult to estimate because they are patchily distributed in most areas even if the habitat seems suitable. The population at Round Hill and Nombinnie Nature Reserves was estimated at 500 in 2017–2018 (NSW OEH 2018), with 100 in Riverland Reserve in 2012 (P. Waanders 2012, unpublished), about 2400 in Murray–Sunset in 2018–2019 (S. Verdon unpublished) and about 200 in the Big Desert (R. Clarke unpublished). The maximum population has been estimated from the mean of the product of recorded densities (2 birds/km2, Woinarski [1987]; 10 birds/km2, Moise [2008]) and the AOO.
Trend justification
A continuing decline is likely. Fire and drought have greatly reduced the population size in Riverland Biosphere Reserve, and Billiatt and Ngarkat Conservation Parks within the last three generations (P Waanders, L Ireland, C Hedger, R Boulton unpublished) but trends outside South Australia are unclear. In the last 30 years, they have disappeared from the northern Eyre Peninsula (since 1996), Mount Boothby and Ferries-McDonald Conservation Parks (since 1980s) and all habitat east of the Murray River in South Australia; from Pulletop Nature Reserve (since 1982), near Ennisvale, Springwood Station and Tarawi Nature Reserves (since 1996) in New South Wales; and Hattah-Kulkyne National Park, Bronzewing and Wathe Flora and Fauna Reserves (since 1980s; DEWLP 2016). Historically large parts of its range have been lost to habitat conversion, however recent declines have been primarily driven by fires.
Red-lored Whistlers occur in semi-arid parts of New South Wales, Victoria and South Australia, Australia. The largest occupied areas are Nombinnie and Round Hill Nature Reserves in New South Wales, Murray-Sunset National Park and smaller contiguous reserves and the Big Desert in Victoria; and Riverland Biosphere Reserve and Ngarkat Conservation Park in South Australia where there are also single records from Billiatt and Bakara Conservation Parks which may be dispersing individuals but could be part of unsurveyed populations (BirdLife Australia 2020, eBird 2020, L. Ireland unpublished) and they may persist on private land near Meningie were last seen 2002 (MK Todd unpublished). In the last 30 years, they have disappeared from the northern Eyre Peninsula (since 1996), Mount Boothby and Ferries-McDonald Conservation Parks (since the 1980s) and all habitat east of the Murray River in South Australia; from Pulletop Nature Reserve (since 1982), near Ennisvale, Springwood Station and Tarawi Nature Reserves (since 1996) in New South Wales; and Hattah-Kulkyne National Park, Bronzewing and Wathe Flora and Fauna Reserves (since the 1980s; DEWLP 2016). Individuals are often recorded at sites distant from known resident populations, suggesting genetic connectivity among well-separated locations.
Red-lored Whistlers occur in mallee with a dense spinifex Triodia spp. understorey, in heath-dominated mallee and in open mallee with a well-developed shrub understorey, particularly broombush, Melaleuca uncinata. They take arthropods, mainly insects, and very occasionally seeds and fruit on or near the ground or in the canopy (Woinarski 1987, Higgins and Peter 2002, Moise 2008) by snatching and gleaning. They lay 2–3 eggs in a cup nest often close to the ground (Higgins and Peter 2002). Depending on rainfall, recolonisation after fire usually occurs within ten years, but densities start to decline after several decades, with lower altitude sites remaining suitable for longer (Woinarski 1987, Higgins and Peter 2002, Clarke 2005, Connell et al. 2017, S. Verdon unpublished).
The principal threat is from fire; extensive and comprehensive fires such as occur in heat waves during drought (DELWP 2016) and a fire regime that precludes the development of suitable habitat (Connell et al. 2019) are both detrimental. Large-scale fire has been particularly prevalent in the Murray Mallee in the last 20 years (Avitabile et al. 2013). However, the thinning of the understorey when there has been no fire also seems detrimental so that active management of the fire regime is necessary (MK Todd, S Verdon unpublished). The abundance of whistlers is also strongly influenced by rainfall (Connell et al. 2017) with drought greatly reducing population densities (P. Waanders, C. Hedger, L. Ireland unpublished). The threat from fire is likely to intensify given projections of increases in frequency and severity of extreme fire weather (Di Virgilio et al. 2019; Dowdy et al. 2019), drought (Evans et al. 2017) and heat waves (Herold et al. 2018). Grazing by goats Capra hircus, rabbits Oryctolagus cuniculus and kangaroos Macropus spp. diminish habitat value by simplifying habitat structure (Giljohann et al. 2017). Cutting of broombush Melaleuca uncinata is an ongoing but minor threat, particularly outside protected areas (MK Todd unpublished). Predation by cats Felis catus (Woinarski et al. 2017) and foxes Vulpes vulpes (DELWP 2016) may also affect population size although there is no direct proof. Much of the habitat was modified historically by pastoralism and then cleared for wheat farming (Fahey 2017). The species has been replaced by Gilbert's Whistler P. inornata at Chapman's Bore and parts of the western Murray Mallee, probably as a result of changes in habitat, however competition between the two species is thought to be secondary compared to other threats (Garnett et al. 2011).
Conservation Actions Underway
Listed as threatened under appropriate legislation. The majority of remaining populations are in protected areas. Central NSW population is regularly monitored and counted as part of the Saving Our Species program of the Office of Environment and Heritage in NSW. Surveys have been conducted for the species elsewhere in NSW but have failed to find any other resident populations (M. Todd in litt. 2016). The species is included in the Threatened Mallee Birds Project and resulting Conservation Action Plan (Boulton and Lau 2015). Advice on threatened mallee birds is being incorporated into fire planning and response. Grazing pressure is being reduced on most reserves where this is a problem.
Text account compilers
Symes, A., Dutson, G., Garnett, S., Taylor, J., North, A., Benstead, P., Vine, J.
Contributors
Boulton, R., Egan, D. & Todd, M.
Recommended citation
BirdLife International (2024) Species factsheet: Red-lored Whistler Pachycephala rufogularis. Downloaded from
https://datazone.birdlife.org/species/factsheet/red-lored-whistler-pachycephala-rufogularis on 23/12/2024.
Recommended citation for factsheets for more than one species: BirdLife International (2024) IUCN Red List for birds. Downloaded from
https://datazone.birdlife.org/species/search on 23/12/2024.