Population information

Order name Ciconiiformes
Family name Threskiornithidae
Scientific name Threskiornis spinicollis Common name Straw-necked Ibis
Population name Australia
Breeding range Australia (not Tasmania) Non-breeding range Australia, S New Guinea
Red List Category Least Concern
Ramsar regions Oceania

Conservation Framework

Conservation framework Notes
No conservation frameworks

Population size

Publication Start year End year Minimum Maximum Estimate quality Notes References Actions
WPE 4 2003 2003 1,000,000 1,000,001 [S4361] [R341]
WPE 1 1993 1993 500,000 500,000 [R665]
WPE 2 0 0 500,000 500,000 [R667]
WPE 3 2002 2002 500,000 500,000 [R604]
WPE 5 1983 2009 100,000 1,000,000 Best guess [S6477] [R341] [R1022] [R1023] [R1149] [R1150]

Population trends

Publication Start year End year Trend Trend quality Notes References Actions
WPE 4 1990 2000 FLU [R341]
WPE 1 0 0 Unknown
WPE 2 0 0 Unknown
WPE 3 0 0 Unknown
WPE 5 1982 2011 DEC? No idea [R1113] [R1023] [R1022]

Population 1% level

Publication Yearset 1 percent Note
WPE 4 2006 10000
WPE 1 1994 5000
WPE 2 1997 5000
WPE 3 2002 5000
WPE 5 2012 10000


  • R341 - Jaensch, Roger, August 2005. Detailed data and notes on numbers and distribution of waterbirds in Australia, updated from Jaensch, 2003, and derived from more than 90 Australian sources including Wetlands International, Birds Australia and Jaensch, 2003,
  • R665 - Unpublished information provided by IWRB Specialist Research Groups
  • R667 - Unpublished information supplied by Wetlands International Specialist Groups, 1997.
  • R604 - Specialist]] Unpublished information supplied by Wetlands International Specialist Groups, 2002.
  • R1022 - BirdLife International. 2012h. Important Bird Areas factsheet: Gwydir Wetlands. Downloaded from?http://www.birdlife.org?on 30/04/2012
  • R1023 - BirdLife International. 2012i. Important Bird Areas factsheet: Narran Wetlands. Downloaded from?http://www.birdlife.org?on 30/04/2012
  • R1149 - Reid, J.R.W., Kingsford, R.T. and Jaensch, R.P. 2009. Waterbird Surveys in the Channel Country Floodplain Wetlands, Autumn 2009. Report by Australian National University, Canberra, University of New South Wales, Sydney, and Wetlands International, Oceania, Brisbane, for the Australian Government Department of Environment, Water, Heritage and the Arts. 81 pp. Also available online at http://www.lebmf.gov.au/publications/pubs/waterbirds-report.pdf
  • R1150 - Reid, J. and Jaensch, R. 2004. Aerial waterbird survey results. Section 4.7, pp 472-493 in, Costelloe, J.F., Hudson, P.J., Pritchard, J.C., Puckridge, J.T. and Reid, J.R.W. AridFlo Scientific Report: Environmental Flow Requirements of Arid Zone Rivers with Particular Reference to the Lake Eyre Drainage Basin. School of Earth and Environmental Sciences, University of Adelaide, Adelaide. Final Report to DLW and BC and DEH. Also available online at http://www.lebmf.gov.au/publications/aridflo.html
  • R1113 - Kingsford, R.T. and Johnson, W. 1998. Impact of water diversions on colonially-nesting waterbirds in the Macquarie Marshes of arid Australia. Colonial Waterbirds 21: 159-170.


  • S4361 - 344: breeds in colonies, the largest of any waterbird in Australia, commonly tens of thousands of pairs but erratically, when inland floodplains inundated, with largest 200,000 pairs. Population probably around 1 million, and 1% threshold of 10,000 is considered justifiable.
  • S6477 - Data are inadequate for a numerical estimate; many birds occur in dryland habitat that is not surveyed. Numbers possibly approach or exceed 1 million after major breeding events but that is rare now due to impacts of river regulation and irrigation on viability of largest breeding colonies (some smaller colonies are intact).

Copyright Wetlands International 2012

Citation: Wetlands International (). "Waterbird Population Estimates" . Retrieved from wpe.wetlands.org on