NT
Short-tailed Grasswren Amytornis merrotsyi



Justification

Justification of Red List Category
This species has been uplisted to Near Threatened because it occupies a small area, within which it occurs at a moderately small number of locations and is inferred to be undergoing declines in its range size, quality of habitat and number of mature individuals. These declines are thought to be driven by anthropogenic and lightning-induced fires, the former being used to create habitat for sheep grazing.

Population justification
The largest subpopulation, in the south-east of Ikara-Flinders Ranges National Park, is estimated to number 1,000 pairs, with another c.3,000 individuals in three other subpopulations of A. m. merrotsyi. A. m. pedleri numbers c.900 mature individuals, thus the total global population size has been estimated at c.6,000 mature individuals (Garnett et al. 2011).

Trend justification
The population of A. m. pedleri is about 900 mature individuals and stable, but, given the frequency of extensive fires, it is assumed that the population of A. m. merrotsyi is likely to be declining at an unknown rate (Garnett et al. 2011).

Distribution and population

This species is endemic to Australia, where it is patchily distributed in southern South Australia (Garnett and Crowley 2000, Garnett et al. 2011). A. m. merrotsyi occurs in four subpopulations between Mt Neil in the north and Nelshaby in the south, and A. m. pedleri has at least three subpopulations in the central and western Gawler Ranges (Higgins et al. 2001). The largest subpopulation, in the south-east of Flinders National Park, is estimated to number 1,000 pairs, with another c.3,000 individuals in three other subpopulations of A. m. merrotsyi. A. m. pedleri numbers c.900 mature individuals, thus the total global population size has been estimated at c.6,000 mature individuals (Garnett et al. 2011). The nominate subspecies may no longer occur at the southern extremity of the range, and the species is inferred to be declining owing to an increase in the extent and frequency of fires within its range (Garnett et al. 2011).

Ecology

The species inhabits rocky hilltops, ridges and hillsides covered with clumps of spinifex Triodia spp. tussock grassland and scattered shrubs.  A. m. merrotsyi recolonises 5–7 years after a fire and reaches peak densities 10–30 years after fire (G. Carpenter in litt., in Garnett et al. 2011). It forages mostly on the ground, eating seeds, fruits, insects and other invertebrates (Higgins et al. 2001).

Threats

An increase in the frequency and extent of fires, both natural and anthropogenic, along with grazing, represent the most significant threats to the species (Higgins et al. 2001). A single fire event has the potential to eliminate a whole subpopulation (G. Carpenter in litt., in Garnett et al. 2011). The habitat of the southern subpopulation near Quorn is burned regularly to make it suitable for sheep grazing and much of the region is burned on average every ten years (Whisson 1999, in Garnett et al. 2011). Predation by introduced Red Fox Vulpes vulpes may be significant as intensive fox baiting over 20 years has resulted in comparatively high population densities in south-east of Flinders Ranges National Park (Carpenter 2004, in Garnett et al. 2011).

Conservation actions

Conservation Actions Underway
The Flinders Ranges and Gawler Ranges National Parks protect significant parts of the range.

Conservation Actions Proposed
Monitor population trends at key sites. Research optimal fire regimes for the species. Assess the impact of predation by foxes. Actively manage fires to reduce overall extent and frequency. If appropriate continue and extend fox baiting (Garnett et al. 2011).

Acknowledgements

Text account compilers
Symes, A., Temple, H., North, A.

Contributors
Watson, C.


Recommended citation
BirdLife International (2021) Species factsheet: Amytornis merrotsyi. Downloaded from http://www.birdlife.org on 09/12/2021. Recommended citation for factsheets for more than one species: BirdLife International (2021) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 09/12/2021.