Threatened Species of the Northern Territory
HORSFIELD’S BUSHLARK
(Tiwi Islands subsp.)
SINGING BUSHLARK
Mirafra javanica melvillensis
Conservation status
Australia: Critically Endangered
Northern Territory: Vulnerable
Description
The Singing Bushlark is a small short squat
lark with a short robust bill and a rounded
head. The top of the head and neck appear
black, streaked with rufous and there is a
distinct pale-buff eyebrow. The upperparts
are mottled
Photo: BirdLife Australia*
Springs Region and the eastern Simpson
Desert.
brownish-grey with rufous edging to the
feathers, and a strongly rufous wing. The
underparts are pale cream-rufous with strong
dark streaking on the breast. The legs are
short. Birds can raise a short crest, but this is
not usually visible.
Distribution
Singing Bushlarks are found throughout
South-East Asia, the Philippines and Australia,
as well as across northern sub-Saharan Africa,
the Arabian Peninsula and southern Asia.
They are widespread in Australia and occur in
all mainland Australian states and territories.
As a species, it is probably one of the most
numerous birds in the Northern Territory
(NT), with estimates of 6 million birds. Most
records come from the savanna belt, including
the Victoria River District and the Barkly
Region, but there are also records from the
Darwin-Daly Region, Arnhem Land, Alice
For more information visit www.denr.nt.gov.au
Known locations of the Tiwi Singing Bushlark
There are eight recognised subspecies of
Singing Bushlarks, four of which occur in the
NT. One of these, M. j. melvillensis is
endemic to the Tiwi Islands, and all records so
far have come from Melville Island. This
subspecies is the focus of this listing. It is the
only subspecies of Singing Bushlark that
occurs on the island. Conservation reserves
where reported: None.
Ecology
Bushlarks generally are grassland birds,
particularly occupying perennial tussock
grasslands with rank cover. They tend to be
less numerous as tree-cover increases. The
Tiwi Singing Bushlark is largely confined to
treeless plains dotted within the tropical
forest and woodland matrix that dominates
the islands. These treeless plains consist of
Acacia open shrublands with Sorghum
grassland understorey.
Singing Bushlarks forage entirely on the
ground, feeding on seeds and invertebrates.
They make a nest on the ground, under cover,
and lay three to four eggs per clutch. In the
NT, most breeding occurs in November-early
April.
Conservation assessment
There are few records of the Tiwi Singing
Bushlark and in 2000-2001, the most
intensive fauna survey of the islands by
Woinarski et al. (2003) recorded them in only
two sites from a total of 351 survey sites and
400 person-days of opportunistic surveys
across the range of terrestrial habitats on the
islands. They appear confined to areas of
treeless plains which cover only 191 km2 on
the islands, and not all of this is likely to be
suitable habitat.
The status of the Tiwi Singing (Horsfield’s)
Bushlark was assessed in 2010 by Garnett et
al. (2011). They estimate the population to be
less than 1 000 individuals, and classify the
species as Vulnerable.
This species qualifies as Vulnerable in the NT
(under criterion D1), based on:
•
An very small total population size
(<1 000).
Threatening processes
The area of treeless plains habitat of the Tiwi
Singing Bushlark was reduced last century by
replacement by plantations of exotic
Caribbean pines. Such replacement is unlikely
to occur in the future. More recent
commercial plantations on Melville Island with
non-native Acacia mangium have replaced
eucalypt forests and woodlands, not treeless
plains. It is not known whether this clearance
of native forest for plantations will be
beneficial or detrimental for this subspecies.
Fire regimes on the Tiwi Islands have changed
significantly and are now characterised by
larger, hotter and more frequent fires in
accessible areas and less frequent fires in
more remote areas (Garnett et al. 2011). The
spread of weeds, both grassy weeds and feral
plantation species, into treeless plains is likely
to alter their vegetation composition and
structure, as well as fuel loads. Grazing and
disturbance by feral water buffalo, pigs and
horses may also degrade treeless plain
habitats, though they may also reduce grass
density, which may be beneficial.
Consequently, threats to Tiwi Singing
Bushlarks are not clearly defined at present,
and the subspecies may have always been in
low numbers.
Conservation objectives and management
The primary conservation objectives are to
maintain and enhance the condition of
treeless plain areas on the Tiwi Islands, and to
retain a stable population of Tiwi Singing
Bushlarks. Management objectives include
developing and implementing a monitoring
program for the subspecies.
Compiled by
Simon Ward
[updated December 2012]
[EPBC update July 2015]
References
*BirdLife Australia www.birdlife.org.au
Garnett, S.T., Szabo, J.K., and Dutson, G. (2011). The
action plan for Australian Birds 2010. (CSIRO
Publishing/Birds Australia, Melbourne.)
Higgins, P.J., Peter, J.M. and Steele, W.K. (eds)(2001).
Handbook of Australian, New Zealand and Antarctic
Birds. Volume 5: Tyrant flycatchers to chats. (Oxford
Univ. Press, Melbourne.)
Woinarski, J., Brennan, K., Hempel, C., Armstrong, M.,
Milne, D., and Chatto, R. (2003). Biodiversity
conservation on the Tiwi islands, Northern Territory.
Part 2. Fauna. 127 pp. (Department of Infrastructure
Planning and Environment: Darwin.)
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