Kangaroos

In this subsection I have included animals belonging to the Kangaroo family (Macropodidae). This second-largest family of marsupials includes herbivores adapted to moving by leaps and bounds.

 

Appearance

Members of this family are of medium to large size (0.5 - 90 kg). They have long, narrow hind feet and powerful hind limbs. The fourth toe of the hind foot is the longest and strongest. It lies in a line with the main limb elements and transmits the thrust of hopping. The outside (fifth) toe is also large. As is true of all members of their order, macropodids are syndactylous, that is, the second and third toes are fused for most of their length, but end in separate nails that are used for grooming. The tail is long and heavy in most macropodids, but it is not prehensile. Instead, it is used as a balancing or stabilizing organ.

To move fast, most members of this group use a bipedal form of hopping. The animal takes off with a push from its large and muscular hind limbs and lands on its hind feet and tail. At high speeds (up to 50 km/h!) the tail remains off the ground and is used for balance. At slow speed, macropodids land on their forelimbs and tail, while swinging their hindlimbs forward.

While a tail and hind feet specialized for hopping characterize most macropodids, a few have shorter and broader hind feet and a shorter tail than the kangaroos and wallabies. These forms include the tree-kangaroos (genus Dendrolagus), which are excellent climbers; pademelons (genus Thylogale), which often walk with a quadrupedal gait; and the relatively short-tailed quokkas (genus Setonix).

Macropodids have a long and narrow skull, usually a long rostrum, and a head that seems small relative to the size of the body. 

Distribution

Macropodids are found in Australia, New Guinea, and on some nearby islands.

Diet

Macropodids are grazers and browsers. They have a complex sacculated stomach, and the compartments serve as sites for fermentation (digestion) by microorganisms. Some species even regurgitate food for additional chewing.

Behavior

Most macropodids are nocturnal, while a few are diurnal or crepuscular.

Reproduction

Gestation in macropods lasts about a month, being slightly longer in the largest species. Typically, only a single young is born, weighing less than 1 g (0.035 oz) at birth. They soon attach themselves to one of four teats inside the mother's pouch. The young leave the pouch after five to 11 months, and are weaned after a further two to six months. Macropods reach sexual maturity at one to three years of age, depending on the

species.

The lifespan of these animals varies depending on the species.

Incaptivity

Enclosures for macropods must take into account the unique requirements of the species and wherever possible mimic the natural environment for the species. Both the physical and psychological needs must be met. Many macropods are prone to stress and stress-related disease. Enclosures should provide a stress-free environment that includes adequate shelter, privacy, elevation, climbing structures and other furniture. All animals should be provided with a means of sheltering from wind, rain and extremes of sunlight and temperature. Although many macropods live in arid environments they do not necessarily cope well with high ambient temperatures. Most species seek refuge from heat during the day. Conversely, heating may be required for some species in cold climates. Many macropod species are nocturnal and are better suited to nocturnal displays.

Where possible, enclosures should allow for easy observation of animals from a distance to minimise stress from being approached too closely. Areas should also be provided where animals can have privacy and seek refuge and hide from other animals in the enclosure. Enclosures should be large enough to allow for the normal activity of the species and prevent overcrowding and for animals to get away from each other. Most macropods require a relatively larger area than other marsupials.

Macropod enclosures are best kept simple and free of obstacles. Fencing and other enclosing structures must be carefully designed. Macropods are prone to fence-running when stressed or being pursued and will collide with the fence or obstacles protruding from it. Fence posts should be outside the enclosure so the inside fence line is smooth and free of obstacles. Where possible, fence lines should be relatively straight and without corners. The height of the fence will depend on the species with the highest fences, about 1.8–2.4 m high, required for kangaroos at. Fences should be made of chainlink or similar mesh or solid material. Mesh size should be small enough to prevent the animals getting their heads and arms through if there are other macropods in an adjacent enclosure. Males often fight through fences, causing abrasions and even severe bite wounds on the arms. The fence should also prevent entry of predators such as foxes and dogs by preventing access to the enclosure through, under and over the fence. If climbing species (musky rat-kangaroo, rock-wallabies, tree-kangaroos, bettongs) are to be held in unroofed enclosures, the fences should be made of material (smooth tin, corrugated iron, timber or brick) that is unclimbable or is rimmed by a 45° outrigger 0.5 m wide facing into the enclosure. When alarmed, macropods are prone to colliding with fences if they are not clearly visible. Shadecloth or hessian attached to the fence is useful as a site barrier and should always be in place when introducing animals to new enclosures.

Enclosure furniture and planting should be appropriate for the species. Arboreal species such as tree-kangaroos should be provided with adequate climbing structures and thick shade. Rock-wallabies require a rocky mound with crevices for hiding. Macropods can be very destructive to vegetation and plants within an enclosure. Plants need to be chosen carefully for resilience and toxicity. Most plants will need protection from the animals, with barriers. Many macropods use grass tussocks, bushes and shrubs to hide or nest in.

Substrates should be readily cleanable to allow regular removal of faecal material. They should be well-drained and not remain damp, to prevent the build-up of parasite oocysts and larvae, and bacteria. This is particularly important around feed and water points where animals congregate. Uneaten food must be removed daily to prevent build-up of bacteria and fungi and not attract pests. Grass, sand, soil or leaf litter are suitable substrates for most macropod species.

Feed and water containers should prevent contamination with faeces and urine, prevent access by pests and be readily cleaned and disinfected. This will aid in preventing build-up and spread of parasitic and bacterial infections and attracting pests. Feed areas should be under cover. Feed dishes, troughs, pellet hoppers and hay racks should be kept off the ground. This reduces the risk of food contamination with faeces and urine by preventing animals sitting in them. Feed areas should ideally have a concrete slab so that spilled feed and faeces can easily be picked up. Several feed areas may be required if there are a large number of animals in the enclosure. Fresh clean water should be provided in ponds, troughs or self-filling waterers.