There are three major threats to Lumholtz's tree-kangaroos:
Only 12% of the Lumholtz's tree-kangaroo habitat is in protected areas, i.e. national parks. The highest densities of Lumholtz's tree-kangaroos though occur on the Atherton Tablelands, mostly on private land where their habitat is prone to alteration, fragmentation or destruction for commercial purposes, such as agriculture, dairy farming and logging for timber.
Although they appear to live quite happily in small isolated patches of rainforest and in riparian strips of vegetation along watercourses, populations are not able to sustain themselves in these kinds of habitats because the actual numbers are too low to maintain genetic health. They need regular influx from stable core populations, such as those at Curtain Fig Forest, the Malanda Scrub and the Crater (Mt. Hypipamee) NP. In order to travel to new areas to live, predominantly young males in their dispersal phase have to cross open ground or roads, where they frequently get killed by dogs and cars.
If frightened they just 'freeze' and blend in with their surroundings unrecognisably, which characterises their main predator avoidance behaviour. When even more distressed they vocalise with a "fft-fft-fft" sound and/or leap off a tree (from as high as 15m) and take flight on the ground. This might be a good strategy to escape their natural predators such owls, eagles and pythons, but on the ground they have no chance against dogs or dingoes.
As a result of a TKMG community survey in 2000 we received reports of more than 300 dead tree-kangaroos over the last 15 years. 75% of dead tree-kangaroos were road kills and about 10% were dog kills. The actual numbers almost certainly are much higher. One of the causes of those deaths is the lack of appropriate dog control on the Atherton Tablelands.
Activities of the TKMG like the introduction of tree-kangaroo road signage in high tree-kangaroo roadkill areas, the promotion and implementation of wildlife tunnels in road upgrades as well as revegetation initiatives and wildlife corridor plantings aim to alleviate the pressures on this unique species.