Download Noisy Scrub-bird - Australia`s Threatened Birds

Species Conservation Summary
Noisy Scrub-bird
Atrichornis clamosus (Gould,1844)
Atrichornithidae
Conservation status
Endangered B1ab(iii,v)+2ab(iii,v)
Reasons for listing
The population is restricted to few locations resulting in
a very small extent of occurrence and area occupied. The
recent series of large wildfires and some unexplained
smaller-scale declines suggests a probable continuing
decline in habitat quality and number of mature
individuals
Status 2000
Vulnerable D2
Reason for change in 2010: multiple large fires and some
smaller local losses suggest a continuing decline
Status 1990
Endangered B1ab(ii,v)+2ab(ii,v), C2a(ii)
Reason for change in 2000: decline reversed and a
second viable subpopulation established
Taxonomy
No infraspecific taxa described
Taxonomic uniqueness: high (1 genus/family, 2 species/
genus, 1 subspecies/species)
Range
Endemic to south-west Western Australia. In the 19th
century, recorded from 3 main areas: near Waroona,
Margaret River-Augusta area and Albany area (Whittell
1943). No confirmed records from 1889 to 1961, when
<100 individuals rediscovered at Two Peoples Bay, east of
Albany (Webster 1962; Danks et al. 1996). Natural colonists and translocations have created 1 extensive subpopulation at a handful of locations from Two Peoples Bay to
Cheyne Beach (Danks et al. 1996; Gilfillan et al. 2009;
Department of Sustainability, Environment, Water, Population and Communities 2011). There is a second introduced subpopulation at Bald Island; but birds
reintroduced to the Darling Ranges, Porongurup
National Park and Mt Taylor have not been recorded
breeding (Tiller 2009a; Comer et al. 2010; Department of
Sustainability, Environment, Water, Population and
Communities 2011).
Abundance
Fires in 2000–2004 reduced the mainland subpopulation
from 569 singing males in 1999 and 733 in 2001 to 278 in
2005; numbers are expected to recover, although it may
take 10 years before the habitat is suitable (Comer 2002;
Comer et al. 2005; Danks and Comer 2006). In 2005, the
mainland subpopulation included 4 singing males at
Moates Lake-Gardner Lake, 126 at Mount Gardner, 37 at
Angove River-Normans Inlet, 32 at Mount Manypeaks,
53 at Waychinicup and 26 at Mermaid (Department of
Sustainability, Environment, Water, Population and
Communities 2011). Based on a ratio of 2.5 individuals
for each territorial male (Danks et al. 1996), the mainland subpopulation was estimated at 695 mature birds.
Numbers counted during surveys at Mt Gardner were 132
in 2007, 121 in 2008 and 119 in 2009 (A. Burbidge and S.
Comer in litt.). The second subpopulation on Bald I.
totalled 99 territorial males (c. 248 mature birds) in 2010
and 95 in 2007, an increase from 2 territorial males in
1993, 10 in 1997 and 37 in 2001 (Danks et al. 1996; Cowen
2009; Department of Sustainability, Environment, Water,
Population and Communities 2011).
Ecology
Good Noisy Scrub-bird habitat comprises dense vegetation in particular understorey and shrub layer, with
sedges or piles of debris for nesting interspersed with
small open areas with a thick accumulation of leaf-litter
and a well developed litter fauna for feeding (Danks 1991;
Danks et al. 1996). The female lays a single egg in a domed
nest, which is usually built in a clump of sedge. The main
food is terrestrial arthropods (Danks and Calver 1993).
Most occupied sites have not been burnt for >10 years, the
sites on Mt Gardner having a post-fire age of >50 years
and on Bald I. of >120 years. All habitat on Manypeaks
was burnt in a wildfire in 2004, and some territories
recolonised by 2006, but only in areas where the fire was
intense and vegetation regeneration had been rapid (S.
Comer in litt.). Historically, the species may have occupied the ecotone between swamp vegetation and forest
dominated by Jarrah Eucalyptus marginata and Marri E.
calophylla (Smith 1985), although such habitat is rare
within the species’ current range. Dispersal appears to be
along corridors of closed vegetation, the birds readily
crossing roads but not cleared land (Danks 1991). A generation time of 6.0 years (BirdLife International 2011) is
derived from an average age at first breeding of 2.0 years
and a maximum longevity of banded birds of 10.0 years
(Australian Bird and Bat Banding Scheme).
© 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
IUCN Red List assessment data
Estimate
Reliability
Extent of occurrence
trend
250 km2
stable
high
high
Area of occupancy
trend
140 km2
stable
high
high
950
decreasing
medium
medium
B
Endangered: EOO <5000 km2, AOO <500 km2, at ≤5
locations with plausible future threat, inferred
continuing decline in area and quality of habitat, and
no. birds
No. subpopulations
2
high
C
Vulnerable: population <10 000 mature individuals,
inferred continuing decline, 250–1000 mature
individuals in largest subpopulation
No. locations
5
medium
D
Vulnerable: population 250–1000 mature individuals,
≤5 locations with plausible future threat
Generation time
E
Not applicable: no population viability analysis
undertaken
No. of mature individuals
trend
Largest subpopulation
Global population share
700
medium
6.0 years
medium
100%
high
Threats
Extensive high-intensity bushfire is the major threat, as
the species depends on long unburnt habitat and has
limited dispersal abilities. In 1994, a fire at Mt Taylor
destroyed most of a recently translocated population,
with remaining birds disappearing during the subsequent
year (A. Danks in litt.). A fire burnt 4500 ha at Mt Manypeaks in 2004–2005, a loss of one-third of suitable
habitat and 56% of singing males in the Albany area
(Comer and Burbidge 2006; Danks and Comer 2006).
Although a small amount of breeding was recorded
within 4 years after the fire, it could be up to 10 years
before the habitat is suitable again (Danks and Comer
2006; Tiller 2009b). Except for a handful, all birds are on
protected land, but habitat clearance on private land
could cut corridors, preventing dispersal and fragmenting subpopulations. Breeding success is relatively good,
but various native and introduced mammals and reptiles
may raid nests and kill adults (Smith and Robinson 1976;
Danks et al. 1996). The reasons for the decline in the subpopulation at Mt Gardner, and the disappearance of the
self-established subpopulation around Lake Gardner, are
unknown but could be related to the length of time since
fire, increased predation by feral cats Felis catus or the
removal of birds for translocation (Danks 1997; Comer
and Danks 2000).
4. Continue to support coordination of management by
the South Coast Threatened Bird Recovery Team
Conservation objectives
1. Population numbers and area of occupation
increased or maintained
2. Management options increased through improved
ecological knowledge
Danks A (1991) The role of corridors in the management of an
endangered passerine. In Nature Conservation 2: The Role of
Corridors. (Eds DA Saunders and RJ Hobbs) pp. 291–296.
Surrey Beatty, Sydney.
Information required
1. Trends in all known subpopulations
2. Effect of fire age on vegetation structure and food
availability
Management actions required
1. Active fire management around all scrub-bird
locations
2. Continue habitat management and threat abatement
of all occupied areas
3. Continue translocation program
Bibliography
BirdLife International (2011) ‘Species factsheet: Atrichornis
clamosus’. Retrieved 17 January, 2011 from <http://www.
birdlife.org/>.
Comer S (2002) Noisy Scrub-birds in the Albany Management
Area. South Coast Threatened Birds News 6, 3.
Comer S, Burbidge A (2006) Manypeaks rising from the ashes.
Landscope 22, 51–55.
Comer S, Danks A (2000) ‘Noisy Scrub-bird Recovery Plan
Annual Report 1999’. South Coast Threatened Birds Recovery Team, Albany.
Comer S, Danks A, Burbidge AH (2005) Noisy Scrub-birds,
Western Whipbirds and wildfire at Mt Manypeaks. Western
Australian Bird Notes 113, 16–17.
Comer S, Danks A, Burbidge AH, Tiller C (2010) The history
and success of Noisy Scrub-bird re-introductions in Western Australia: 1983–2005. In Global Re-Introduction Perspectives: Additional Case-studies from Around the Globe.
(Ed. PS Soorae) pp. 187–192. IUCN/SSC Re-Introduction
Specialist Group, Abu Dhabi, UAE.
Cowen S (2009) DNA of a ‘phoenix’: a study of genetic variability in the Noisy Scrub-bird. South Coast Threatened Birds
News 13, 5.
Danks A (1997) Conservation of the Noisy Scrub-bird: a review
of 35 years of research and management. Pacific Conservation Biology 3, 341–349.
Danks A, Burbidge AA, Burbidge AH, Smith GT (1996) ‘Noisy
Scrub-bird Recovery Plan’. WA Dept Conservation & Land
Management, Perth.
Danks A, Calver MC (1993) Diet of the Noisy Scrub-bird
Atrichornis clamosus at Two Peoples Bay, south-western
Western Australia. Emu 93, 203–205.
Danks M, Comer S (2006) Mt Manypeaks update: Project
Phoenix rises! South Coast Threatened Birds News 10,
10–11.
© 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.
Department of Sustainability Environment Water Population
and Communities (2011) Atrichornis clamosus. 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>.
Smith GT, Robinson FN (1976) The Noisy Scrub-bird: an
interim report. Emu 76, 37–42.
Gilfillan S, Comer S, Burbidge AH, Blyth J, Danks A, Newell J
(2009) ‘South Coast Threatened Birds Recovery Plan. Western Australian Wildlife Management Program No. 44’. WA
Department of Environment and Conservation, Perth.
Webster HO (1962) Rediscovery of the Noisy Scrubbird Atrichornis clamosus. Western Australian Naturalist 8, 57–59.
Smith GT (1985) Population and habitat selection of the Noisy
Scrub-bird, Atrichornis clamosus. Australian Wildlife Research
12, 479–485.
Tiller C (2009a) Noisy Scrub-bird translocation news. South
Coast Threatened Birds News 13, 10.
Tiller C (2009b) Noisy Scrub-birds return to Mt Manypeaks.
South Coast Threatened Birds News 13, 2.
Whittell HM (1943) The Noisy Scrub-bird (Atrichornis clamosus). Emu 42, 217–234.
Comments received from
Allan Burbidge, Sarah Comer
© 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.