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Koala (Phascolarctos cinereus) Fact Sheet: Population & Conservation Status

Population Status

Population estimates

  • Total population estimates (aggregated mean estimates based on state estimates) (McAlpine et al. 2012; Adams-Hosking et al. 2016; Woinarski and Burbidge 2016)
    • 330,000 individuals (all age classes)
      • 300,000 mature individuals
  • Population estimates by state in Australia (McAlpine et al. 2012, except as noted)
    • Queensland
      • About 78,000 (35,000-150,000) individuals
        • Vulnerable in southeast Queensland (Jackson 2015)
        • Distribution in Queensland reduced by 30% in last 100 years (Gordon et al. 1990; Gordon et al. 2006)
    • New South Wales
      • 36,350 (20,000-75,000) individuals
      • Uncommon in most locations (Jackson 2015)
    • Victoria
      • 182,500 (75,000-325,000) individuals
      • Considered common to abundant (Jackson 2015)
      • Introduced populations (after extinctions)
    • South Australia
      • 33,320 (19,000-52,000) individuals
      • Became extinct in this region by 1920; later re-introduced (Jackson 2015)
  • Historical estimates
    • Estimated that 10 million koalas existed in Australia when koala fur trade began in the late 1800s (Australia Koala Foundation, personal communication, 2018; also see AKF publication)
      • Fur trade records: at least 8 million koalas killed for fur between 1888 and 1927


Population structure

  • DNA studies show low variability in the Victoria and South Australia populations (Sherwin et al. 2000)
    • Most individuals probably originate from French Island translocations
    • French Island population was started with only a few individuals from the mainland

Conservation Status

IUCN Status

  • Vulnerable (2014 assessment) (Woinarski and Burbidge 2016, 2020)
    • Populations have experienced about a 30% decline over the past 18-24 years
    • Populations likely to be impacted by climate change, due the impacts of drought on available forest habitat
    • Past assessments
      • 2008: Least Concern
      • 1996: Lower Risk/near threatened

CITES Status

  • Not listed (UNEP 2018)


  • Considered endangered in some state territories (Queensland, New South Wales, and Australian Capital Territory) (Australian Government 2022)

U.S. Fish and Wildlife Service

  • Threatened (U.S. Fish & Wildlife Service 2018)
    • United States federal agencies must consider the impact of their actions on the koala
    • Commercial activity or trade in koalas prohibited by the United States, except under a threatened species permit

Threats to Survival

Habitat destruction, degradation, and fragmentation

  • Urban and agricultural development
  • Roads, railways, powerlines
  • Logging, timber thinning, destruction of undergrowth
  • An estimated 80% of koala habitat has been destroyed due to development, drought, and fires


  • Often on islands where introduced

Hit by motor vehicles

  • Deaths mostly during breeding season, when males are moving about more frequently


  • Injured or killed by dogs, dingoes, feral cats, feral foxes, owls, and Wedge-tailed Eagles
  • Young most vulnerable


  • Chlamydia
    • May cause infertility and sometimes death
    • Affects some populations more than others

Climate change

  • In western Queensland and New South Wales (Natural Resource Management Ministerial Council 2009):
    • Changes in koala food trees' structure and chemistry
    • Changes in range of habitat species - both food and shelter trees
    • More intense and frequent drought
    • More intense and frequent wildfires
    • Changes in average temperature, rainfall and humidity
    • Contractions in koala distribution
  • In a population studied in Blair Athol Coal Mine area of central Queensland (Ellis et al 2010b):
    • Protection of trees in riparian areas may not be the best conservation strategy for protecting koalas in hotter weather
      • Species of riparian trees present may not be well-adapted to survive serious environmental changes

Conservation History


  • Introduced onto Phillip and French Islands (Victoria)
    • French Island population (Chlamydia-free) prospered; became overpopulated by the 1920s


  • Commercial harvesting banned in Victoria

Early 20th century

  • Commercial harvesting resulted in millions of pelts for export industry; near extinction resulted


  • Extinct in South Australia; subsequently introduced to Kangaroo Island and a few localities on mainland
  • Official translocation program began; individuals moved from French Island to Victoria islands

1940s: Populations moved to mainland Victoria and South Australia

2001: Listed in State of the Environment report of the Commonwealth as one of eight pest species of Australia (Gordon et al. 2008).

Prior to 2012: (Natural Resource Management Ministerial Council 2009)

  • Not listed under Australian government's national environment law (Environment Protection and Biodiversity Conservation Act 1999; each state made own regulations and law
    • While some populations in Victoria and South Australia recently have increased, populations elsewhere declined
    • Status to be reviewed by 30 Sept 2010; severity of threat to koalas overall is disputed (Phillips 2000)
    • Culling not favored; translocation may be only solution to avoid starvation in over browsed areas
  • Various states had different listings for koalas:
    • Queensland - Vulnerable Wildlife (Nature Conservation Act 1992)
    • New South Wales - Vulnerable (Threatened Species Conservation Act 1995)
      • Two additional endangered populations
    • Victoria - not listed (Victorian Flora and Fauna Guarantee Act 1988) but listed as "other protected wildlife" (Wildlife Act 1975)
      • South Gippsland populations may be only endemics left in Victoria
    • South Australia - Protected (National Parks and Wildlife Act 1972) but delisted in 2008
      introduced population on Kangaroo Island, Australia now around 28,000, causing severe environmental damage (Gordon et al. 2008)
  • Recommendations by IUCN Redlist (2009) for action (Gordon et al. 2008)
    • Koala is one of top 10 species in world threatened by climate change
    • Australia should complete and implement National Strategy for Conservation of the Koala
    • Choose appropriate models for assessing diversity of habitats preferred by koalas
    • Conduct regional and local surveys for distribution, tree preferences, key critical habitats
    • Implement regional management plans
    • Manage populations to prevent over browsing
    • Develop positive community support for koala management
  • Protecting native Eucalyptus forests an important strategy for protecting koalas (AKF 2009)


2012: Australian government declares koala populations in Queensland, New South Wales and the Australian Capital Territory as Vulnerable under national environment law (Australian Government 2012)

Page Citations

Adams-Hosking et al. (2016)
Australian Koala Foundation (2009)
Ellis et al (2010b)
Gordon et al. (1990)
Gordon et al. (2006)
Gordon et al. (2008)
Jackson (2015)
Martin (1989)
Martin (2001)
Maxwell et al. (1996)
McAlpine et al. (2012)
Natural Resource Management Ministerial Council (2009)
NCC (2003)
Phillips (2000)
Sherwin et al. (2000)
USFWS Federal Register (2000)
Woinarski and Burbidge (2016)

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