Macropods at Skyrail

Skyrail Nature Diary: August 2013


This month we’ll be looking at macropods along the Skyrail corridor. Macropods are marsupials, generally known as wallabies and kangaroos. A marsupial is a mammal that has two wombs and because of this, the offspring are born very early in their development. Most deposit the newborn foetus in a pouch where it attaches itself to a teat and stays until it’s big enough to move out of the pouch. Macropods are all able to have three joeys in different stages of their life cycle; one outside the pouch, one inside the pouch and one undeveloped foetus in the womb. Macropods are easily identified. The all have hind legs that are adapted to hopping. The foot is modified from the kangaroo’s ancestor, an unknown possum, and has become lengthened with several toes fused together. The legs contain a ligament that works like a spring. So every time a kangaroo lands on the ground after a hop the, ligament absorbs all the energy from the impact and immediately releases it, allowing the kangaroo to hop onwards effortlessly.

This is a very efficient means of locomotion. The two middle toes have been joined by a piece of skin, a phenomenon known as ‘syndactyly’. In possums, this double claw is used for grooming. Most macropods have adapted to eating grass. Unlike cattle, they have teeth in the front of their mouths and literally ‘mow’ the lawn whereas cattle have no teeth at the front and use their long tongues to pull the grass out of the ground. The Swamp Wallaby is the only leaf browser among the macropods today. So what is the difference between a wallaby and a kangaroo? Simply stated it has to do with size. The small macropods are called wallabies while the larger ones are called kangaroos. The wallaroo is considered to be intermediate in size. Even smaller than the wallabies are the rat kangaroos (potoroos, quokkas, bettongs and hare wallabies). These are noticeably smaller and often have different feeding habits to their larger relatives.

The Musky Rat Kangaroo is the smallest and most primitive of all the macropods. The feet are very ‘possum like’ and have the original five toes. Instead of hopping on two legs, these cute little fellows bound through the rainforest on all fours most of the time. These beautiful creatures are one of only two diurnal (out during day time) mammals in Australia. The other is the nearly extinct numbat in Western Australia. The females usually give birth to two joeys at a time and such a family was once spotted at Skyrail’s Red Peak station. Musky Rat Kangaroos eat fallen fruit, mushrooms and insects.

The red-legged pademelon is a cute little macropod that lives in the rainforest. Here in Queensland, they are relatively safe thanks to the Wet Tropics. In New South Wales they are vulnerable due to habitat destruction. pademelons have reddish fur with a white underside. Their ears are small and round. Living in the rainforest has modified their style of hopping. Rather than bounding forward with lots of upward spring, pademelons hop straight forward. This allows them to quickly move through the undergrowth without getting stuck or hitting the numerous obstacles in their way. Pademelons are generally solitary creatures but do occasionally feed together. Their diet consists of fallen fruit, leaves and grasses. The latter shows that they don’t only live in the rainforest.

Rock Wallabies are a group of macropods that excel in hopping around in rocky terrain. They have thickly padded feet that allow them to grip rocks and outcrops while they move through an area. Often these wallabies have dark stripes over their eyes. Rock Wallabies are nocturnal and usually spend their days in caves or under protected overhangs. This kind of habitat is difficult to come by and as a result, these macropods tend to live together in large groups.

Here in North Queensland, the best known colonies live in Granite Gorge near Mareeba, in several areas of the Undara Lava Tubes in the Gulf area, in Chillagoe near the limestone caves and on Magnetic Island. Rock Wallabies eat almost any available plant.

The Agile Wallaby is without a doubt the most common macropod in the north of Australia, especially in the coastal regions. Further inland they are joined by the Eastern Grey Kangaroo and in some areas, the Wallaroo. They are easily identified by the black and white patches on their muzzles. They are social creatures and nocturnal. Early in the morning or just before dusk are the best times to spot them in grassy areas. In Cairns, they are best spotted by the highway near the northern beaches, especially Trinity Beach. Here at Skyrail we often see them in the morning when heading up to Red Peak station.

 

By Tore Lien Linde