As unlikely as it seems, there are indeed kangaroos that spend their lives high in the rainforest canopies of northern Queensland. They are beautiful animals, and they feature amazing adaptations for this arboreal lifestyle.
You can meet one of them, the Lumholtz’s tree kangaroo, right here at Billabong Sanctuary.
WHAT’S IN A NAME?
The genus name is from the Greek dendron, meaning ‘tree’ and lagos, meaning ‘hare’.
The species name lumholtzi is after the Norwegian explorer Carl Sofus Lumholtz who was the first European to record a specimen in 1883.
Thus the scientific name means ’Lumholtz’s hare-like tree dweller’ .
It’s probable that early explorers had a taste for tree kangaroos, and compared them to rabbits (or hares). Even the author Tim Flannery admits “…I can attest that they share with hares a distinctive and delicious gamey flavour!”
They were a traditional staple food for local indigenous people.
In north Queensland the aboriginal name for this tree kangaroo is boongary.
WHERE DOES IT LIVE?
Found only in Queensland, the Lumholtz’s tree kangaroo occurs mostly at high altitudes in the wet tropics, from the Daintree River south to the Kirrama ranges. Their greatest concentration is in fragmented forests of the Atherton Tablelands.
They are generally found in higher elevations, approximately 600 to 1200 metres above sea level (1900 to 4000 ft). They prefer areas with nutrient rich soils.
A second Australian species, Bennett’s tree kangaroo (Dendrolagus bennettianus) is found in only a small area north of the Daintree.
There are 10 other recognised species of tree kangaroo that live in New Guinea and Indonesia, where they inhabit cool and very wet highland rainforests.
Fun Fact: New species of tree kangaroo have been discovered as recently as 1995!
Lumholtz’s tree kangaroo is a solitary species. Males have a home range of about 4 hectares (10 acres) and females have home ranges half that size. Even where they overlap, individuals ignore each other, and they do not defend their territories.
WHAT DOES IT LOOK LIKE?
With its long tail, powerful forearms and relatively short hind limbs, the tree kangaroo bears little resemblance to terrestrial kangaroos.
Lumholtz’s tree kangaroo has dark hair grizzled grey with blackish tips all over its back, and lighter fur on its underbelly. It has a dark face with a pale forehead. The paws and the tip of the tail are black.
The hair forms two whorls over the shoulders, which help to direct rain off this rainforest dweller when it is sitting in a hunched position (its usual resting posture).
It has short, round ears that give its face a teddy-bear-like appearance!
This is the smallest of the tree kangaroos, with males weighing an average of 8 1/2 kg (18.7 lb) and females an average of about 7 kg (15 lb). Average length of the body is about half a metre (20 “), and the tail is much longer than the body!
Fun Fact: This is the largest arboreal mammal in Australia!
The muscular forearms enable the tree kangaroo to easily climb into the canopy. The front paws have 5 digits with long curved claws for clinging to branches. Wrist and shoulder joints are more flexible than those in terrestrial kangaroos, allowing sideways movement for gripping branches.
The hind limbs can move independently of each other and the joints are flexible.
Fun Fact: Tree kangaroos are the only kangaroo that can walk backwards!
All four paws have large fleshy pads on the underside for gripping branches and tree trunks.
The tail is one of the most dramatic features. In the Lumholtz’s tree kangaroo it is up to 15% longer than the body! You would expect the tail to be prehensile in a tree-dwelling animal, but it is not. Instead it helps to balance the animal when perched on a limb and even acts as rudder when it leaps from branch to branch or out of the tree.
Fun Fact: When threatened, the tree kangaroo can jump 15 metres or more to the ground and bound off without injury!
WHAT DOES IT EAT?
Lumholtz’s tree kangaroos feed on the mature leaves of about 40 species of plants, including trees, vines, shrubs and epiphytes. They can even eat some plants that are toxic to most mammals.
They appear to get most of the water they need from their food, and many home ranges do not even include a body of water.
REPRODUCTION
This solitary rainforest tree dweller gives birth to only one joey per year, and it is likely that they are opportunistic; that is, they breed at any time of year if conditions are favourable.
Males may mate with more than one female if their home ranges overlap.
Tree kangaroos are marsupials, or pouched mammals. The young is born undeveloped after about 45 days; it crawls into the pouch where it latches onto a teat. It will remain there for nearly a year!
Fun Fact: Tree kangaroos have the longest gestation period, and among the longest periods of maternal care of all marsupials.
After leaving the pouch at about 300 days, the young will continue to nurse for a month or two, then remain in the mother’s home range for up to 650 days after birth.
The father takes no part in caring for the joey. Mum spends considerable time teaching her offspring which leaves to eat, and how to manoeuvre safely high in the canopy.
She may not give birth to another young for up to 14 months.
Females reach sexual maturity at just over 2 years, and males at about 4 ½ years of age.
Lumholtz’s tree kangaroos may live up to 20 years in captivity!
STATUS IN THE WILD
Lumholtz’s tree kangaroo is listed by the IUCN Red List as Near Threatened. The total population size is estimated to be 10 000 – 30 000 mature individuals. Their reclusive behaviour, and preference for dense, high elevation rainforest makes it difficult to do accurate studies.
Loss of habitat was a major factor in reduction in numbers, but the declaration of the Wet Tropics Wold Heritage area has reduced that threat.
Fragmentation of their habitat and increased human population makes them more vulnerable to car strikes and attacks by dogs.
They tend to remain close to their home range, even if it is disturbed, which puts them at further risk of predation and even starvation.
According to the IUCN, “climate change and associated factors have been predicted to have a major detrimental impact on this species, acting directly or indirectly through reduction in rainforest area, reduction in foliar nitrogen concentration, habitat degradation due to increased incidence of severe cyclones, increased incidence of high temperatures, and reduced incidence of free water in mist.”
LUMHOLTZ’S TREE KANGAROO AT BILLABONG SANCTUARY
We are fortunate to have a Lumholtz’s tree kangaroo on display here in the park.
Dave came to us from Tree Roo Rescue and Conservation Centre Ltd in Malanda. He’d been hit by a car and, among other injuries, had suffered partial loss of sight, and so could not be released back into the wild.
We gave him some time to settle in, and Dave is now happily bouncing around his specially designed enclosure. It has lots of high perches and rope vines to mimic his natural habitat.
We have established a grove of rainforest trees so Dave has fresh browse to munch on every morning. He also gets pellets, sweet potato and other treats.
You will often see Dave up on his favourite branch, hunched over in the typical resting posture of this species. Be sure to have a look at that long tail hanging down!
Dave serves as an ambassador to teach visitors about this little-known species and to create awareness of wildlife conservation in general.
Further Reading
https://www.wettropics.gov.au/site/user-assets/docs/42MacropodsOfTheWetTropics.pdf
https://animaldiversity.org/accounts/Dendrolagus_lumholtzi/
https://www.treeroorescue.org.au/
https://animalia.bio/lumholtzs-tree-kangaroo?endemic=1
https://australian.museum/blog/amri-news/tree-kangaroo-genetics/
https://www.iucnredlist.org/species/6432/21957815#assessment-information
Lumholtz’s Tree Kangaroo. Graeme Newell. Nature Australia Vol 25 No 11. 1997-1998. Pp 30-39
Tree Kangaroos. A curious natural history. 1996. Timothy Flannery, Roger Martin, Alexander Szalay. Illus. Peter Schouten. Reed Book Australia
The Mammals of Australia. Ronald Strachan ed. Reed New Holland