Koalas (phascolarctos cinereus) A recent study by scientists from the University of Queensland and Sunshine Coast found that while koalas spend about 10 minutes a day on the ground, this behavior is linked to two-thirds of the koala fatalities recorded.
The wild koala features a custom-built collar that includes a GPS logger and an accelerometer. Image credit: Ami Fadhillah Amir Abdul Nasir.
The koala population in Australia has diminished by 54% over the past three decades.
Annually, millions of dollars are invested in initiatives aimed at safeguarding koalas, preserving their habitats, and treating various diseases.
Tragically, two-thirds of koala deaths occur on the ground due to vehicle accidents or attacks by dogs.
Despite extensive research, the specifics of how koalas interact with the ground remain largely unknown.
Conventional GPS tracking methods offer limited insight, as they typically document locations only once or twice a day.
“Koalas primarily reside in trees, but increasing land development forces them to descend, significantly raising their risk of injury and death,” stated a student from the University of Queensland.
“Our goal was to gain a deeper understanding of their behaviors during ground movements.”
“Key questions remain regarding how frequently koalas climb down from their trees, the distance they cover, whether they remain on the ground, and what factors influence these choices.”
“Identifying high-risk areas and times, and developing mitigation strategies during these vulnerable moments, is critical to our understanding.”
To fill these knowledge gaps, researchers employed a biologger that captures three-dimensional movements at several hundred points, mapping the koala’s directional movements during specific actions.
They tracked 10 wild koalas using an accelerometer and high-resolution GPS device for an average duration of eight days.
The researchers found that the koalas descended to the ground around three times a day, totaling just 45 minutes.
During these visits, the koalas covered an average distance of 260 meters at a typical walking speed of 1.7 km/h, with occasional bursts of up to 10.4 km/h.
By integrating accelerometer and GPS data, researchers were able to pinpoint specific trees that the koalas traversed between.
“Combining GPS tracks with movement data provides us with an in-depth perspective on how koalas navigate their habitats,” Sparks explained.
“The study confirmed that koalas predominantly stay in trees for sleeping and feeding, yet the extent to which they engage with the ground was startling.”
“We were surprised at the frequency and brevity of their ground activities; they descended only 2-3 times nightly, averaging 10 minutes in total, which is less than 1% of their day.”
“The time they spent sitting and pausing on the ground was nearly equal to the time spent walking, with only about 7% of their ground time dedicated to movement.”
“This suggests that koalas carefully assess their environment while on the ground, possibly weighing the energetic costs of remaining on the ground before deciding to climb a tree.”
This study marks the first detailed documentation of ground movements in wild koalas, raising new inquiries about their navigation in increasingly fragmented habitats.
“Currently, we’re investigating how environmental characteristics influence the time koalas spend in trees,” Sparks noted.
“If we can identify the tree and habitat features that encourage extended periods in the trees, we may be able to manage landscapes in ways that minimize the need for ground travel.”
These findings aim to steer koala conservation efforts, prioritizing specific plant types, enhancing canopy connectivity, and minimizing gaps between safe trees.
This research sheds light on koala behavior and is essential for more effective habitat management, ultimately aiming to lower mortality risks in critical zones.
“This research is just one piece of a larger puzzle, but it significantly enhances our understanding of how koalas interact with an increasingly urbanized environment,” Sparkes added.
The scientists presented their findings on July 1, 2025, at the Society for Experimental Biology Annual Conference in Antwerp, Belgium.
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Gabriella R. Spark et al. “Ordinary” Watch: What do koalas do when they’re not sleeping? SEB 2025 Summary #A16.1
Source: www.sci.news
