Justification of Red List Category
This species is considered Endangered because it has a very small range. Its population comprises small and severely fragmented subpopulations. In the northern part of its distribution, the numbers of locations and birds are rapidly decreasing, but this has little effect on overall population numbers. Although numbers are presently stable, the threat of destructive fires in the majority of this species's habitat means that an overall future decline is very likely.
Garnett et al. (2011) estimate that the declining northern race (monoides) has a population of less than 50 mature individuals and the southern race (brachypterus) is stable at c. 2,500 mature individuals. The overall population is therefore estimated at around 2,550 mature individuals, roughly equivalent to 3,800 individuals in total.
The northern subspecies has decreased from c.206 pairs in 1988 to c.13 pairs in 2007 (D. Stewart in litt. 2007), and although the nominate subspecies is considered stable at present, it is projected to decline in the future as it is likely to suffer declines in its area of occupancy, quality of habitat, and the number of mature individuals and sub-populations owing to destructive fires (Garnett and Crowley 2000).
Dasyornis brachypterus is endemic to Australia. There are two subspecies; a northern race (monoides) in south-eastern Queensland and north-eastern New South Wales and the nominate southern race (brachypterus) in eastern New South Wales and eastern Victoria. D. b. monoides is now Critically Endangered, falling from c.206 pairs in 1988 to c.16 pairs in 1997-1998 and c.13 pairs in 2006-2007 (D. Stewart in litt. 2007). There are currently thought to be fewer than 50 mature individuals in total (Garnett et al. 2011). Populations of D. b. brachypterus are stable at c.2,500 mature individuals (Garnett et al 2011). D. b. brachypterus subpopulations include about 1,250 mature individuals at Barren Grounds, 1,200 at Jervis Bay and 300 at Nadgee/Howe Flat. There are newly established subpopulations at Cataract of 50 individuals and about 10 at Red Rocks.
The species is a ground-dwelling, semi-flightless passerine (Bain and McPhee 2005). The northern population (D. b. monoides) usually inhabits grass tussocks in open forest-woodland, close to rainforest which provides fire refuge. The southern population (D. b. brachypterus) lives in dense, low vegetation, particularly heath, but also in surrounding woodlands. Surveys have noted birds in shrubland dominated by Melaleuca spp. or Leptospermum grandifolium, heath dominated by Hakea teretifolia and Eucalyptus woodland (Bain and McPhee 2005). The impact of fire on the southern subpopulations is very context dependent, being mitigated by a combination of smaller fire size; available refuge habitat; and post-fire feral predator control (Bain et al. 2008, Lindenmayer et al. 2009). Extensive fire can be a catastrophic threat, eliminating the species for at least three years post-fire followed by increasing density until at least 15 years post-fire (Baker 1997). This increase is slower for sites with a post-fire age of over 14 years, compared with sites less than 10 years post-fire, suggesting that after 14 years, sites are reaching their carrying capacity (Bain and McPhee 2005). Feeds near the ground, mainly on small invertebrates with some seeds and small fruits (Gibson and Baker 2004). Breeds annually in spring, laying two eggs (Higgins and Peter 2002). They breed readily in captivity and appear to have high survival rates after translocation or captive breeding and release (Garnett et al. 2011).
The main threat to the northern population is an inappropriate fire regime resulting in unsuitable habitat. If fires are too frequent they eliminate tussocks and enable the invasion by introduced woody weeds. However, when fires are too infrequent the vegetation becomes too dense for nesting and becomes unsuitable habitat through mid-storey shrub and weed encroachment. The preferred fire regime for the northern population is between 3-6 years (Tasker and Watson pers. comm. 2016). Extensive fire is the main threat to the southern population. For the southern population, fire removes dense understorey vegetation, which is the species's preferred habitat (Baker 1997). The species was lost from 10 of 11 known locations in Victoria from fire during 1978–1994 (Clarke and Bramwell 1998). In New South Wales, fires almost eliminated it from Barren Grounds in 1968 and from Nadgee in 1980 (Baker 1998). Single fires could be catastrophic across Howe Flat and Nadgee or Barren Grounds and Budderoo (Baker 2000 in Garnett et al. 2011). Habitat is also degraded by feral pigs Sus scrofa and domestic livestock. Other threats to the species include overgrazing, invasion of habitat by exotic weeds and predation by foxes Vulpes vulpes and feral cats Felis catus. Birdwatching may be a threat to the northern population, with repeated playback of calls having the potential to disturb breeding birds.
Conservation Actions Underway
The northern population has been the focus of extensive conservation actions. Fences and fire-breaks have been constructed. Research into preferred fire regimes is being completed in 2016 and results indicated a requirement for a frequent fire regime with interfire intervals of 3-6 years (Tasker and Watson pers. comm. 2016). Integrated fire and weed management is being implemented on key NSW sites. Some pig and cat control is undertaken. Vegetation monitoring sites are being established. The majority of the territories in the northern population have been mapped. Current efforts to locate occupied sites include using trained dogs in SE Queensland and NE New South Wales (I. Gynther in litt. 2016). This population is now the focus of an intense captive breeding programme with the aim of re-establishing the species at several sites. The three main southern populations in New South Wales (Barren Ground-Budderoo, Jervis Bay-Booderee and Nadgee Nature Reserve) have undergone surveys and initial ecological research. Habitat mapping has been conducted at Jervis Bay. Research has been conducted over three years into the ecology and translocation of 50 birds from Bhewerre Peninsula to Beecroft Peninsula in the Jervis Bay region, including habitat selection by the species after fire. A second translocation of approximately 50 birds from Barren Grounds Nature Reserve to Sydney Catchment Authority (SCA) lands has been undertaken. Other fire ecology research has been conducted. Research on the southern population has shown that not all habitat needs to be constantly maintained as greater than 14 years unburnt, as long as large, adjacent and long unburnt (for over 20 years) areas are protected for emigration from and recolonisation of more recently burnt areas (Bain et al. 2008, Lindenmayer et al. 2009). Annual monitoring is carried out at Jervis Bay National Park, Barren Grounds Nature Reserve and Nadgee Nature Reserve. At Nadgee, habitat monitoring is conducted every two years. Fox control is carried out for the Jervis Bay-Booderee and Barren Grounds-Budderoo populations. Weed control, particularly of Bitou Bush has been undertaken at Booderee National Park, though recent studies have shown that the species can utilise Bitou Bush as post-fire refugia. The vegetation where the northern population can be found is currently being investigated as to how it interacts with fire. Results indicate that most areas need to be burnt on a 4 – 5 year cycle to maintain a healthy understory (D. Stewart in litt. 2016).Conservation Actions Proposed
Northern population: Continue to survey for a new population in the vicinity where the species once occurred. Release captive-bred birds into areas with small populations and where the species has been recently recorded. Southern population: Monitor populations annually. Monitor habitat every two years. Control foxes and weeds. Develop contingency plans for fire and conduct ecologically sensitive hazard reduction burns at central populations (Barren Grounds-Budderoo and Jervis Bay-Booderee National Parks) to reduce the impacts of large intense fires. Encourage public participation and provide information. Minimise the loss of habitat on private land from future residential and commercial developments in the Jervis Bay area. Retain and manage known or potential habitat corridors between reserves (OEH 2012). Continue to monitor the density of the species in long unburnt habitat and study the relationship between the species and the post-fire age of habitat (OEH 2012). Both populations: Determine a suitable fire management strategy. Continue studies on population genetics. Control weeds, foxes and cats.
18-22 cm. Medium-sized, sturdy, grey-brown passerine. Sexes similar, female slightly smaller. Dark cinnamon-brown upperparts. Rufous-brown upperwing and uppertail. Grey-brown underparts, faintly scalloped. Grey-brown sides of belly and flanks. Brown undertail-coverts. Dull rufous-brown undertail. Red iris. Juvenile, pale brown iris. Similar spp. Similar in jizz and skulking behaviour to Rufous Scrub-bird Atrichornis rufescens but lacks barring on upperparts. Voice Frequent, ringing contact call, loud, melodious song and chattering, staccato, squeaky notes.
Text account compilers
Benstead, P., Garnett, S., McClellan, R., Taylor, J., Allinson, T, Symes, A., North, A.
Baker, L., Gynther, I., Oliver, D., Bain, D., Stewart, D.
BirdLife International (2020) Species factsheet: Dasyornis brachypterus. Downloaded from http://www.birdlife.org on 04/12/2020. Recommended citation for factsheets for more than one species: BirdLife International (2020) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 04/12/2020.