Download Eastern Bristlebird (southern)

Subspecies Conservation Summary
Eastern Bristlebird (southern)
Dasyornis brachypterus brachypterus (Latham, 1802)
Dasyornithidae
Conservation status
Endangered B1ab(ii)+2ab(ii)
Reasons for listing
Extent of occurrence <5000 km2 and occupies
<500 km2, occurs at 5 locations and there is a continuing
decline in AOO
Status 2000
Endangered B1ab(ii)+2ab(ii)
Status 1990
Endangered B1ab(ii)+2ab(ii)
Taxonomy
D. b. monoides (north-eastern New South Wales and
south-eastern Queensland) is Critically Endangered, and
the species is Endangered
Taxonomic uniqueness: high (1 genus/family, 3 species/
genus, 2 subspecies/species)
Range
Near-coastal distribution in New South Wales and east
Gippsland, Victoria, historically from Myall Lakes to
Gippsland Lakes (Schodde and Mason 1999). In central
NSW, subpopulations persist around Barren Grounds
Nature Reserve including Budderoo National Park, and
Jervis Bay including Bherwerre and Beecroft Peninsulas,
and remnants and/or recent colonists in some additional
locations including Red Rock Nature Reserve (Baker
1997, 1998). Near NSW/Vic border, remains at Nadgee
Nature Reserve and Howe Flat, Croajingolong National
Park with small numbers elsewhere in this contiguous
habitat (Baker 1997; Bramwell 2008). In 2003–2005, successfully reintroduced to Beecroft Peninsula (Bain and
French 2009). In 2008, released at Cataract on the Woronora Plateau, where breeding (Baker 2009). However, AOO
probably continuing to decline with relatively recent contraction in range in Vic.
Abundance
The total population is estimated as 2500 mature individuals. Potentially viable subpopulations at Barren
Grounds (maximum c.1250 individuals), Jervis Bay
(c.1100 individuals) and Nadgee/Howe Flat (300), newly
established at Cataract (50) and very few individuals elsewhere including c.10 at Red Rocks (Bain and McPhee
2005; Bramwell 2008; J. Baker in litt.). Genetic analysis
indicates 3 closed subpopulations (Roberts et al. 2011).
The number of individuals is assessed here as stable, as
increases in translocated subpopulations compensate for
likely losses to fire.
Ecology
Inhabits dense, low vegetation, in a variety of habitat
types. Often found in heath, including a variety of heath-
land, sedgeland and swamp communities, but also in
open sclerophyll woodland or forest with an understorey
of shrubs and a dense ground layer of grasses or Bracken
Pteridium esculentum. Occasionally in temperate rainforest (Department of Sustainability, Environment, Water,
Population and Communities 2011). Eliminated by
intense fire but can recolonise recently burnt areas if
there are adequate nearby unburned refuges (Bain et al.
2008). Population density increases until 10–20 years
after fire, when 3–5 birds/10 ha, but individuals have
overlapping home territories of c.10 ha (Baker 2001; Bain
and McPhee 2005). Most remaining subpopulations are
probably isolated as they are poor at long distance dispersal, however records 15 km west of Barren Grounds at
Fitzroy Falls and Upper Kangaroo Valley indicate some
dispersal through suitable corridor habitat. Feeds mainly
on small invertebrates, also seeds and small fruits (Gibson
and Baker 2004). Breeds annually in spring, laying 2 eggs,
but rarely raises more than 1 fledgling (Higgins and Peter
2002). A generation time of 5.2 years (BirdLife International 2011) is derived from an average age at first breeding of 1.6 years, an annual survival of adults of 77.0%,
and a maximum longevity in the wild of 7.3 years, all
values elicited from an expert committee.
Threats
Extensive fire is the main current threat (Baker 2000). The
species was lost from 10 of 11 known locations in Vic. from
fire during 1978–1994 (Clarke and Bramwell 1998). In
NSW, 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 (J. Baker in litt.). Fire
destroys cover, but too infrequent fire can cause the vegetation to become too dense for nesting (Bain et al. 2008).
However, birds can avoid fire by moving to unburnt areas
and returning later when conditions are more suitable, so
patches of unburnt habitat and other refuges are of great
importance (Bain et al. 2008). However, unlike the populations further north, the Nadgee population has not
recovered from extensive fires in 1972 and 1980 (J. Baker in
© Birds Australia 2011
Published by CSIRO Publishing, http://www.publish.csiro.au/
Citation: Garnett ST, Szabo JK, Dutson G (2011) The Action Plan for Australian Birds 2010. CSIRO Publishing, Melbourne.
Current eligibility against IUCN Red List Criteria
IUCN
category
A
Criteria eligibility
Not applicable: past, current or future population
declines are thought unlikely to exceed 20% in any
3-generation period
B
Endangered: EOO <5000 km2, AOO <500 km2, at ≤5
locations with plausible future threat, inferred
continuing decline in AOO
C
Not applicable: no continuing population decline or
extreme fluctuations
IUCN Red List assessment data
Estimate
Reliability
670 km2
stable
high
medium
205 km2
decreasing
medium
low
2500
stable
high
medium
No. subpopulations
3
high
No. locations
5
low
Extent of occurrence
trend
Area of occupancy
trend
No. of mature individuals
trend
D
Vulnerable: ≤5 locations with plausible future threat
Largest subpopulation
E
Not applicable: no population viability analysis
undertaken
Generation time
litt.) and the range has contracted substantially in Victoria.
Predation by foxes Vulpes vulpes and feral cats Felis catus
may be significant (Lindenmayer et al. 2009). Other possible threats include overgrazing, infestations of habitat by
exotic plants and disturbance by humans (Department of
Sustainability, Environment, Water, Population and Communities 2011). Historically the range has been greatly
reduced by clearing and degraded by fire.
Conservation objectives
1. An increasing population
2. Viable populations at more than 5 locations
Information required
1. Impacts of introduced predators, particularly in
combination with fire
2. Reasons for the failure of the Nadgee subpopulation
to recover
Management actions required
1. Prepare and implement fire management plans for all
subpopulations
2. Develop contingency plans in case of fire including
emergency evacuation, assisted habitat recovery and
translocation
3. Control foxes and cats where vulnerable to predation,
particularly after large-scale fire
4. Control weeds that exclude bristlebirds
5. Investigate the need for further translocations
Bibliography
Bain D, French K (2009) Impacts on a threatened bird population of removals for translocation. Wildlife Research 36,
516–521.
Bain D, McPhee N (2005) Resurveys of the Eastern Bristlebird
Dasyornis brachypterus in central-eastern New South Wales
1999–2001: their relationship with fire and observer competence. Corella 29.
Bain DW, Baker JR, French KO, Whelan RJ (2008) Post-fire
recovery of eastern bristlebirds (Dasyornis brachypterus) is
context-dependent. Wildlife Research 35, 44–49.
Baker J (1997) The decline, response to fire, status and management of the Eastern Bristlebird. Pacific Conservation Biology
3, 235–243.
Baker J (1998) ‘Eastern Bristlebird Recovery Plan 1997–2002’.
NSW NPWS, Sydney.
Baker J (2000) The Eastern Bristlebird: cover-dependent and
fire-sensitive. Emu 100, 286–298.
Global population share
1250
high
5.2 years
low
100%
medium
Baker J (2001) Population density and home range estimates for
the Eastern Bristlebird at Jervis Bay, south-eastern Australia. Corella 25, 62–67.
Baker J (2009) Assessment of Eastern Bristlebird habitat: refining understanding of appropriate habitats for reintroductions. Ecological Management and Restoration 10, S136–S139.
BirdLife International (2011) ‘Species factsheet: Dasyornis
brachypterus’. Retrieved 17 January, 2011 from <http://
www.birdlife.org/>.
Bramwell MD (2008) The Eastern Bristlebird Dasyornis
brachypterus in East Gippsland, Victoria, 1997–2002. Australian Field Ornithology 25, 2–11.
Clarke R, Bramwell MD (1998) The Eastern Bristlebird Dasyornis brachypterus in East Gippsland, Victoria. Australian Bird
Watcher 17, 245–253.
Department of Sustainability, Environment, Water, Population
and Communities (2011) Dasyornis brachypterus. In ‘Species
Profile and Threats Database’. Department of Sustainability, Environment, Water, Population and Communities,
Canberra. Retrieved 24 February, 2011 from <http://www.
environment.gov.au/sprat>.
Gibson L, Baker J (2004) Diet of the Eastern Bristlebird Dasyornis brachypterus in New South Wales. Corella 28, 79–81.
Higgins PJ, Peter JM (Eds) (2002) Handbook of Australian, New
Zealand and Antarctic Birds. Volume 6: Pardalotes to Spangled Drongo. Oxford University Press, Melbourne.
Lindenmayer DB, MacGregor CA, Wood JT, Cunningham RB,
Crane M, Michael D, Montague-Drake R, Brown D, Fortescue M, Dexter N, Hudson M, Gill M (2009) What factors
influence rapid post-fire site re-occupancy? A case study of
the endangered Eastern Bristlebird in eastern Australia.
International Journal of Wildland Fire 18, 84–95.
Roberts DG, Baker J, Perrin C (2011) Population genetic structure
of the endangered Eastern Bristlebird, Dasyornis brachypterus;
implications for conservation. Conservation Genetics.
Schodde R, Mason IJ (1999) The Directory of Australian Birds:
Passerines. CSIRO Publishing, Melbourne.
Comments received from
Jack Baker, Allan Burbidge, Andrew Burbidge, Les
Christidis, Hugh Ford, Tim Holmes, Richard Loyn,
Peter Menkhorst, Charles Meredith, Damon Oliver,
Penny Olsen, David Watson
© Birds Australia 2011
Published by CSIRO Publishing, http://www.publish.csiro.au/
Citation: Garnett ST, Szabo JK, Dutson G (2011) The Action Plan for Australian Birds 2010. CSIRO Publishing, Melbourne.