Description

The Lumholtz’s tree-kangaroo is the smallest of the tree kangaroo species, but one of the largest of the arboreal mammals in Australia.  This arboreal species spends most of its life in the canopy of the Australian rainforest. Their muscular and powerful forelimbs and broad hind feet allow them to move in both a quadrupedal and bipedal motion. They have a long tail in comparison to their body size which they primarily use for balance and is not prehensile.  Their specially adapted ankle joints allow them greater rotation to use their hind feet to mould around the tree trunks whilst ascending and descending.  Their hind feet are also much less elongated than their kangaroo relatives, having become shorter and more broad creating a greater surface area for improved grip in the trees.

Long, curved claws are present on all five digits of the forepaws. The hind paws include a large fourth digit and medium fifth digit; the first and second digits are syndactylous, each with its own claw.

This cryptic animal is aided by its fur colouration which can vary greatly from pale grey to black and chestnut.  Its cream coloured belly contrasts with its distinct black fore and hind paws and black facial mask.  The fur is generally short and dense. Adult males average around 7.25 – 9.85kg  whilst the adult females average 6.6-7.75kg (Newell 1998).  Whilst this species is often difficult to spot in their natural habitat, even to the most well trained eye, its long pendulous tail of around 69cm in length can often be seen hanging below a tree branch even whilst sleeping.

This animal is commonly referred to as nocturnal however could more accurately be referred to as ‘cathemeral’, meaning ‘intermittently active throughout the 24h period’. (Tree kangaroo and mammal group 2014)  During periods of sleep the animal’s head sinks onto the chest or even down in between the feet, depending on the animal’s position on a branch, in a fork, or within a vine tangle.

Habitat and Distribution

The Lumholtz’s tree-kangaroo is found in North Queensland from west of Ingham in the Cardwell range to west of Daintree in the Carbine range, an area of approximately 5500km². (Flannery et al.1996) Within this distribution tree kangaroos are rarely observed within lowland regions of below 300m.

This species is more commonly observed in fragmented rainforests on the basalt soils of the Atherton tableland where recent surveys suggest more abundance at elevations above 700-800m. Within the Wet tropics region the species can be found in a range of forest types from wet sclerophyll to riparian and complex rainforest.  This environment is heavily fragmented and has been  since the late 1800s. These fragments are considered vital for the continued survival of the species and most are on private lands (Coombes 2005). These fragments provide “stepping stones “for wildlife movements between fragments and larger areas of forest (Laurance 1990a, Winter 1991)

Conservation Status

Although listed by the IUCN as least concern much of the Lumholtz’s tree-kangaroo habitat is protected under the Wet Tropics World Heritage Area, it is common in suitable habitat, tolerant of some degree of habitat degradation, much of its range is contained within a protected area. (http://www.iucnredlist.org/2015)

The species appears to have been able to persist in the mosaic of fragmented habitat (particularly where there are available habitat corridors). On the Atherton Tableland, increased fragmentation makes them more vulnerable to predation by dogs, although strategic reforestation on the Atherton Tableland opens the possibility of some recovery of its original area of occupancy in the future (Maxwell et al. 1996). In agricultural areas where it occurs, predation by dogs and road kills also represent threats.

Information taken from the IUCN Red List of Threatened Species. Version 2014.3 www.iucnredlist. Downloaded on 15^th January 2015

Diet

The Lumholtz’s tree-kangaroo is a specialist arboreal folivore that have been observed utilising  130 species of plants from 45 families (Procter-Gray 1984, Newell 1999b).  They have been recorded eating not only leaves of tree species but a variety of vines, fruits, flowers and the petioles of some species.

Within the mosaic of rainforest segments and deforested agricultural land within the Atherton tableland this species has also been noted feeding on invasive weed species such as wild tobacco and lantana.  Newell (1999b) recorded that D. lumholtzi used a small number of trees frequently and a larger suite of trees much less regularly, which was found to be common place with other folivores such as possums and koalas.

All kangaroos and wallabies are foregut fermenters (i.e. they break down their food in the first part of the stomach), however the tree-kangaroos are the only marsupial arboreal folivores that ferment their browse in the foregut. Possums and koalas utilise the hind gut.

Information taken from the http://www.tree-kangaroo.net/; Newell 1999b; Procter-grey 1985.

Breeding and Lifecycle

The Lumholtz’s tree-kangaroo is primarily a solitary marsupial.  Tree kangaroos are believed to be polygamous with the male’s home range overlapping that of one or more females.  During breeding when the female is in oestrus cycle of 47-64 days, males will approach the females to breed.

The Lumholtz’s tree-kangaroo has a gestation period (pregnancy) of 42-48days.  Pouch life is 246-275 days and weaning generally occurs between 87-240 days. At around 164-192 days the joey makes short excursions from the pouch where the young climb around and the mother is usually following close by.

Sexual maturity is reached with females as early as 2.04 years and males 4.6 years however has been documented at younger than 3 years (Clare Anderson pers comm)

Studies of captive animals suggest there is no defined breeding season for D. lumholtzi (Procter-Gray 1985. Johnson 1995)  Tree kangaroos have one birth at a time with a mean interval of 1.4 years.

There is little information regarding the lifespan of the Lumholtz tree-kangaroo, but the Matchies tree-kangaroo, a closely related tree kangaroo, has been reported to live for up to 20 years in captivity. (Martin, 2005)

Additional Information

Tree Roo Rescue and Conservation Centre (TRRACC) http://www.treeroorescue.org.au/

A non-profit organisation that rescues and rehabilitates, orphaned, injured or displaced tree kangaroos for release back into the wild or for life in captivity as breeding animals for education and conservation in Zoos. A vision to assist in the prevention of the extinction of Tree kangaroos.

Tree kangaroo and Mammal Group (TKMG) www.tree–kangaroo.net/

The Tree-Kangaroo and Mammal Group (TKMG) is an incorporated community group based on the Atherton Tablelands in Far North Queensland, Australia, made up of local residents interested in, and concerned for, the conservation of North Queensland’s rich mammal fauna.

The Zoo and Aquarium Association acknowledges

Wildlife Habitat

for providing the factsheet information above.