On Wild Koala Day, 3 May, people all around the world celebrate koalas living wild, in forests. Why does it matter where they live, you might wonder? Well, koalas living in nature do amazing things, and we are always learning more about them.
Here are the latest, most surprising and exciting facts about koalas.
a wild koala drinking rain as it runs down the tree trunk. Pic Koala Clancy Foundation
1. Koalas do drink!
It took a tour operator to discover that koalas do drink, while its raining. Echidna Walkabout/Koala Clancy Foundation researchers noticed koalas drinking rain running down tree trunks and branches, as early as 2007. Their observations contributed to this important University of Sydney study by Dr Valentina Mella:
https://onlinelibrary.wiley.com/doi/abs/10.1111/eth.13032 Mella VSA, Orr C, Hall L, Velasco S, Madani G. An insight into natural koala drinking behaviour. Ethology. 2020; 126: 858–863. https://doi.org/10.1111/eth.13032
https://doi.org/10.1093/biosci/biad044 John T Van Stan, Scott T Allen, Douglas P Aubrey, Z Carter Berry, Matthew Biddick, Miriam A M J Coenders-Gerrits, Paolo Giordani, Sybil G Gotsch, Ethan D Gutmann, Yakov Kuzyakov, Donát Magyar, Valentina S A Mella, Kevin E Mueller, Alexandra G Ponette-González, Philipp Porada, Carla E Rosenfeld, Jack Simmons, Kandikere R Sridhar, Aron Stubbins, Travis Swanson, Shower thoughts: why scientists should spend more time in the rain, BioScience, Volume 73, Issue 6, June 2023, Pages 441–452, https://doi.org/10.1093/biosci/biad044
2. A vaccine to protect wild koalas against chlamydia is working really well.
The new University of Sunshine Coast koala chlamydia vaccine is showing impressive results: infection decreased by 82% as a result of vaccination, and infection loads also decreased.
Read about it here:
Desclozeaux, M., Robbins, A., Jelocnik, M., Khan, S.A., Hanger, J., Gerdts, V., Potter, A., Polkinghorne, A. and Timms, P., 2017. Immunization of a wild koala population with a recombinant Chlamydia pecorum Major Outer Membrane Protein (MOMP) or Polymorphic Membrane Protein (PMP) based vaccine: New insights into immune response, protection and clearance. PloS one, 12(6), p.e0178786. https://doi.org/10.1371/journal.pone.0178786
Articles about his here:
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3. (Some) First gum leaves after fire are good eating for koalas.
After a bushfire, eucalyptus trees produce special leaves out of their trunks and branches. In some species of eucalyptus, these epicormic leaves are more nutritious for koalas than normal leaves.
Read about it here:
Lane, M.R., Youngentob, K.N., Clark, R.G. and Marsh, K.J., 2024. The nutritional quality of post-fire eucalypt regrowth and its consumption by koalas in the New South Wales Southern Tablelands. Australian Journal of Zoology, 71(3). https://doi.org/10.1071/ZO23024
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4. A police researcher successfully fingerprinted some koalas!
Koalas are one of few animals that have unique fingerprints like humans. Police Researcher Kiara Ingram-Nader found that using passive human fingerprint detection methods on koala fingermarks actually worked. Koalas could be assessed and potentially identified.
Slide from Kiara Ingram-Nader’s presentation at the National Koala Conference in 2023
A koala’s hand. Pic Koala Clancy Foundation
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5. Chilled Koala sperm survives longer than any mammal!
University of Queensland Associate Professor Steve Johnston and team have have chilled koala sperm for 42 days and found it is still capable of producing healthy joeys. In other species, chilled sperm only lasts 4 to 6 days (dogs) up to 14 days (humans).
Read all about it here:
Johnston, S.D., McGowan, M.R., Phillips, N.J. and O’Callaghan, P., 2000. Optimal physicochemical conditions for the manipulation and short-term preservation of koala (Phascolarctos cinereus) spermatozoa. Journal of reproduction and fertility, 118(2), pp.273-282. https://rep.bioscientifica.com/downloadpdf/view/journals/rep/118/2/273.pdf
Slides from Assoc Prof Steve Johnston’s presentation at the National Koala Conference in 2023
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6. Wildlife crossings actually work for koalas.
From Emerald in central QLD to Port Stephens, NSW, koalas are using specially-made wildlife crossings to avoid death on the roads. See some examples here:
https://www.moretondaily.com.au/news/koalas-on-camera-crossing-safely
https://www.abc.net.au/news/2021-11-17/koala-sightings-central-qld-emerald-good-news/100624968
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7. Clearing of eucalyptus forest causes koalas the most stress, more than fires, being hit by cars or attacked by dogs.
University of Queensland Researcher Edward Narayan has measured stress levels in koala poo and found that the destruction of their habitat causes them much more stress than anything else.
Dr Edward Narayan presenting his findings at the National Koala Conference in 2023
Read all about it here:
Narayan, E., 2019. Physiological stress levels in wild koala sub-populations facing anthropogenic induced environmental trauma and disease. Scientific Reports, 9(1), p.6031. https://www.nature.com/articles/s41598-019-42448-8