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Wouldn’t it be easier to cull to get their numbers down? In 1996, following advice from an independent Koalas on Island taskforce, the following methods of management were established: surgical sterilisation to reduce population growth, Fast facts: translocation from critically damaged areas Scientific name: cinereus to the mainland and habitat restoration to replenish native vegetation. Breeding season: October to May (mainly November to March) was rejected as a management option due to widespread community concerns in Length of pregnancy: 35 days and overseas. The South Australian Litter size: 1 (twins rare) Government is also a signatory to the National Koala Conservation and Management life: 6 to 8 months, permanently out Strategy 2009–2014, which rejects culling as a of pouch by 9 months management option. This approach appears Independence: at 12 months old to be working with the population halved in 2010 compared to 2001 and marked recovery Sexual maturity: at 2+ of tree condition in some areas. Longevity: average 15+ years (females) and What about fencing and metal ‘collars’ 12+ years (males) around trees to prevent koalas climbing Weight: average 8.5 kg (females) and 12 kg up them? (males) Fencing is not feasible on a large scale for a Period of activity: mostly at night number of reasons, including: »» Fences may exclude native species such Leaf consumption: up to 1 kg of leaves per as: echidnas, , and 24 hours possums, as well as stock that rely on the Additional information trees and surrounding habitat for survival. Lee, AK Handasyde, KA and Sanson, GD. History of Koalas on KI »» It is difficult to build fences in riverine (editors) 1991. Biology of the Koala. Surrey »» Koalas were not on (KI) at environments (where most of the suitable Beatty and Sons Pty Ltd, and World Koala the time of European settlement. Research Corporation Pty Ltd. trees grow) when water levels continually »» 18 koalas were introduced to Flinders change and there is flood damage. Lee, A and Martin R. 1996. The Koala: A Chase in the 1920s from French Island, »» Fencing koalas out of areas just makes the natural history. University of . problem worse elsewhere. Press, Sydney, Australia. »» Tree damage due to overbrowsing by »» Metal collars around tree trunks are useful koalas was first recorded in Flinders Chase for protecting isolated trees but are not Martin, R and Handasyde, K. 1999. The in 1965. To reduce overbrowsing koalas feasible in most areas due to overlapping Koala: natural history, conservation, and were translocated from Flinders Chase to tree canopies which allow koalas to move management. Australian Natural History the Cygnet River in the 1950s and 60s. between trees. Series, 2nd Edition. University of New South Wales, Sydney, Australia. »» Overbrowsing damage evident in Cygnet River Valley by early 1990s. For more information Masters, P Duka, T Berris, S and Moss, G. 2004. Koalas on Kangaroo Island: from introduction »» Today, koalas are found across Kangaroo Please see the Natural Resources Island except on the Dudley peninsula. Kangaroo Island website to pest status in less than a century. Wildlife Research 31, 267–272. Highest densities are along river systems. www.naturalresources.sa.gov.au/kangarooisland

CONTACT Natural Resources Kangaroo Island 37 Dauncey Street Kingscote SA 5223 P 08 8553 4444 E [email protected] www.naturalresources.sa.gov.au/kangarooisland Frequently asked questions Why not move koalas from Kangaroo Island to other regions in Australia? Why is it important to manage koalas on Kangaroo Island? Natural Resources Kangaroo Island (NRKI) only relocates koalas to the south-east of the state, The introduced koala population on KI has where they once occurred as a natural part of resulted in large areas of (gum) the local ecosystem. trees dying as a result of overbrowsing. Overbrowsing is the consumption of leaves to Koalas are sterilised before relocation to avoid such an extent that all foliage is removed from creating overpopulation problems in their new the tree canopy and the tree eventually dies. habitat. However, the number of koalas that can be relocated from Kangaroo Island to this Koala management is essential to protect area is limited by the available habitat. the unique environments of Kangaroo Island. The Island has an extremely high Koala densities and habitat condition are conservation value, with large areas of intact monitored in the relocation areas to ensure native vegetation, a high number of species that the number of koalas released will not found only on Kangaroo Island and healthy damage the local ecosystems. populations of species rare or threatened on mainland Australia. The Island is also free of Releasing Kangaroo Island’s koalas into feral pests, such as foxes and rabbits, which the wild in other states of Australia is are widespread on the mainland. not appropriate for a number of reasons, including: Koala overbrowsing also threatens the survival The KI Koala Management Program »» Koalas in different parts of Australia prefer »» Koalas in SA are also physically distinct of the koalas themselves. To date, there is »» The Kangaroo Island Koala Management different types of eucalypts and many from those in NSW or Qld, being larger no evidence to suggest that koalas can self- Program began in 1996 to protect habitat areas are therefore unsuitable. with longer hair and better suited to the regulate their numbers, as kangaroos do. habitats from overbrowsing and is based colder climates than koalas in northern Without effective management, Kangaroo »» Koala numbers in many areas where there Australia. Thus relocating a larger on a program of koala sterilisation and is suitable habitat are already high. In fact Island’s koalas may eventually consume all translocation. unsuited to the warmer temperatures has the available food within an area, resulting in other regions of southern Australia, such animal welfare issues, as well as putting their own starvation. »» Culling is not permitted under the National as Gippsland and Mt Eccles in Victoria, are their smaller counterparts at a competitive Koala Conservation and Management facing similar problems to Kangaroo Island. disadvantage. Strategy 2009–2014. »» Koalas cannot be relocated to New South »» Extensive surveys in 2001 revealed koalas Wales (NSW) or (Qld) where Can more trees be planted? were far more widespread and abundant koala numbers are declining. The decline Tree planting to restore formerly cleared than previously thought, with an estimated in those states is mainly due to habitat loss habitat is an ongoing and valuable activity 27,000 koalas on the island. and disease, so placing more koalas there but only solves part of the problem. Many would just add to the pressure on food »» Management efforts increased in 2004 in of the trees that are dying because of koalas resources and available habitat. response to the revised estimate. are more than 100 years old and it will take decades to replace their services. »» Surveys in 2010 indicated the population had been reduced to approximately 13,000.

Does this situation only occur on Kangaroo Island? Birdlife Australia No, koalas have reached large numbers and been shown to cause tree deaths in many areas of Victoria and in some parts of where they have been introduced.

FACT SHEET 2017