Lumholtz Tree Kangaroo
Photo: Courtesy of Damon Ramsey
BSc.(Zool) Biologist Guide
Lumholtz Tree Kangaroo: Dendrolagus lumholtzi - The tree-kangaroo’s scientific name Dendrolagus means ‘tree hare.’
- They are a traditional food for Indigenous Australians and people from New Guinea.
- In captivity, they have lived until late teenage years.
Identifying Characteristics: - This is the smallest of all tree-kangaroos, adults weighing just over half as much as Bennett's tree-kangaroos. (Source: Environmental Protection Agency)
- Tree Kangaroo movement is unusual for macropods in the fact that they walk rather than hop.
- Blackish- brown, sprinkled with lighter coloured fur on the lower part of their back.
- Lighter coloured band across forehead and down each side of the face.
- Long forearms which are heavily muscled and hind feet are short and broad.
- Tail is long with the terminal half blackish brown, used for counterbalance in climbing.
- Males and females are similar in colour, but males are noticeably larger.
Distribution and Habitat: - Only 2 species of tree-kangaroos are found in Australia – Lumholtz’s and Bennett’s – and both are restricted to the Wet Tropics. Several other species are found in New Guinea.
- It is a nocturnal animal, thus, its days are spent asleep in a crouched sitting posture in the crown of a tree or branch.
- It occupies upland forests between Ingham and the Carbine Tableland, where the territory of Bennett's tree-kangaroo takes over. (Source: Environmental Protection Agency)
Viewing Opportunities: - Can be viewed with a spotlight, at the Crater National Park, on the Malanda falls Environmental Park walking paths, The Curtain Fig Tree and along the roadway on Thomas Road.
Diet: - Lumholtz’s Tree-kangaroo has a big sacculated stomach that allows large quantities of leaves to be ingested. It is primarily a leaf eater (but leaves have a low nutrient value).
- It is known to feed on the leaves of the Silkwood as well as fruit and maize from farms on the rainforest edge.
- The full range of its diet has not been determined.
Mating and Breeding: - When investigating a receptive female, the male utters a soft clucking sound and softly paws her head and shoulders. Then he follows if she moves away, pawing the base of her tail.
- There does not appear to be a definite breeding season. Only one young is raised at a time. They attach to the one teat (of 4) that has become enlarged prior to birth.
Behaviour: - Although densities may approach 1 per hectare in some places, these animals are essentially solitary, males fighting to the death if enclosed together. (Source: Environmental Protection Agency)
- Feeding aggregations of up to four have been found.
- It sits crouched in the crown of a tree or on a branch sleeping during the day. There is a noticeable parting of the fur behind the shoulders as they sit, which is possibly a device to channel water forwards and backwards in case it rains while they are sleeping.
- As with other kangaroos, the fur is groomed with the syndactylous toes of the hind feet, the strong claws of the fore feet, and the tongue.
- The tree-kangaroo may appear clumsy, but it is an efficient climber. It grips a branch with its long forelimbs and walks (or runs slowly) forwards or backwards with alternate movements of its shorter hind feet. On broader, roughly horizontal branches, the tree-kangaroo may move in the typical kangaroo hopping motion. Its tail serves as a counterbalance.
- It travels tail-first down a tree, holding the trunk with its forelimbs, alternately moving each one down the tree while the soles of its hind feet slide against the bark until it is about 2m above the ground. Then, kicking off from the trunk, it twists in mid-air to land upright. Some animals have been recorded to jump from a tree to the ground from 20m without sustaining any injury, but others have jumped from lower trees and been internally harmed.
- Movement on the ground is by a quadrupedal walk or run or a bipedal hop.
- They are not a very active animal. Research has calculated that only 10 percent of the average Lumholtz’s tree-kangaroo’s time is spent actively – feeding, grooming, moving, and so on.
Evolution: - About one-sixth of the entire kangaroo family is made up of 10 tree-kangaroo species. It is now believed that because of anatomical similarities, they evolved from rock wallabies at least 5 million years ago. (Pademelons are also closely related.)
- The evolution of tree-kangaroos was a reversal of some of the major trends in all macropod evolution. It is unknown why all types of kangaroos descended from arboreal ancestors and adapted to terrestrial life, and why the tree-kangaroos later returned to the trees.
- The tree-kangaroos had to adapt considerably to live in trees. They regained their ability to walk, have proportionally much bigger and stronger forelimbs than those of terrestrial kangaroos, have long curved claws on their front and hind feet, have teeth redeveloped for shearing as opposed to grinding, have short and broad hind feet to improve grip (larger surface area), and have a tail used for balance.
- Fossils of a giant tree-kangaroo, the size of a mature red kangaroo, have been found in New South Wales. They are at least 50,000 years old.
- The 8 species found in New Guinea are divided into 17 subspecies. This diversity may be due to the preference by some species for isolated mountain tops which, combined with New Guinea’s active geology which has caused mountains to grow rapidly, has cut populations off and allowed them to develop differently.
Threats: - Research suggests Lumholtz’s tree-kangaroos prefer forests growing on the Tableland’s rich basalt soils. As this is also the best soil for farming, much of the tree-kangaroo’s habitat has been cleared for farms. They have fortunately been able to survive in the strips along creeks and in areas that are too rocky for farming. However, they mostly live on private land, which is unprotected by World Heritage and National Parks status.
- This extensive clearing of lowland rainforest greatly reduced the range of Lumholtz’s Tree-kangaroo. Highland forest logging is further reducing the range, but it is present in reasonable numbers in several national parks and reserves.
- When on the ground, they are vulnerable not only to dogs, but also to vehicles. Of 27 dead tree-kangaroos examined in the Atherton Tablelands from 1992 to 1994, 11 had been hit by cars, six had been killed by dogs, four by parasites and the others by other causes.
- As a result of the growing concern for the tree-kangaroo’s future, the Tree Kangaroo and Mammal Group was formed. The Group meets at 7.30pm every first Thursday of the month at the Malanda Hotel. Annual membership is $10.
- The Tree Kangaroo and Mammal Group is happy to have received a Natural Heritage Trust grant to examine different rainforest fragments as possible Tree-kangaroo habitat.
Additional Lumholtz Tree Kangaroo Photo
Additional Lumholtz Tree Kangaroo Photo 2
Additional Lumholtz Tree Kangaroo Photo 3 NEW Research Report:
Lumholtz's Tree Kangaroo: Conserving A Rare Marsupial
Marsupials In The Mist, Declining Mountain Top Refuge A worthwhile group dedicated to the preservation of Tree Kangaroos is:
The Tree-Kangaroo and Mammal Group, North Queensland, Australia
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