Kangaroos
Red Kangaroo
The Red Kangaroo (Macropus rufus) is the largest of all kangaroos, the largest mammal native to Australia, and the largest surviving marsupial. It is found across mainland Australia, avoiding only the more fertile areas in the south, the east coast, and the northern rainforests.
Description
This species is a very large kangaroo with short, red-brown fur, fading to pale buff below and on the limbs. It has long, pointed earlobes and a squared-off muzzle. Females are smaller than males and are blue-grey with a brown tinge, pale grey below, although arid zone females are coloured more like males. It has two forelimbs with small claws, two muscular hindlimbs, which are used for jumping, and a strong tail which is often used to create a tripod when standing upright.
The Red Kangaroo's legs work much like a rubber band. The males can leap over nine meters in one leap.
Males grow up to a body length of 1.4 metres (4 ft 7 in) long and weigh up to 85 kg (187.4 lb). Females reach a body length of up to 1.1 metres (3 ft 7 in) long and weigh up to 35 kg (77.2 lb). Tails can be from 0.9 to 1 metre (3.0–3.3 ft) long. The average Red Kangaroo stands approximately 1.5 metres (4 ft 11 in) tall. Accounts of sizes greater than this are not uncommon, with some large males reportedly reaching approximately 2 metres (6 ft 7 in).
The Red Kangaroo maintains its internal temperature at a point of homeostasis about 36°C (96.8°F) using a variety of physical, physiological and behavioural adaptations. These include having an insulating layer of fur, being less active and staying in the shade when temperatures are high, panting, sweating, and licking its forelimbs.
The Red Kangaroo inhabits most of the dry inland of the central part of Australia in small groups called mobs. It prefers open plains where trees and bushes are scarce.
The Red Kangaroo's range of vision is approximately 300° due to the position of its eyes. A human's range of vision is around 180° (if you do not move your eyes, but moving them and keeping your head straight the vision increases to about ~230°).
Behavior
The Red Kangaroo is mainly active in the cool of the evening or night, and lives alone or in small groups called 'mobs' (although food shortages can cause them to congregate into larger groups). Membership of these groups is very flexible, and males (boomers) are not territorial, fighting only after females (flyers) which come into heat. The largest males are dominant, and control most of the matings.
The Red Kangaroo is nocturnal and crepuscular, and largely spends the daylight hours sleeping or otherwise relaxing.
Feeding
The Red Kangaroo prefers to eat grasses and other vegetation. It can go long periods of time without water, as long as it has access to green plants as they have the ability to take moisture out of plants.
The dental formula of a kangaroo is the same dental formula as for macropods:
Breeding
The Red Kangaroo breeds all year round. The females have the unique ability to delay birth of their baby until their previous Joey has left the pouch. This is called embryonic diapause. The gestation period is around 33 days. The young Joey will permanently leave the pouch at around 235 days old, but will continue to suckle until it reaches 12 months of age.
Fighting
When male kangaroos fight, they may appear to be "boxing". They usually stand up on their hind limbs and attempt to push their opponent off balance by jabbing him or locking forearms. If the fight escalates, they will begin to kick each other. Using their tail to support their weight, they deliver kicks with their powerful hind legs.
From Wikipedia, the free encyclopedia
Eastern Grey Kangaroo
The Eastern Grey Kangaroo (Macropus giganteus) is a marsupial found in southern and eastern Australia, with a population of several million. It is also known as the Great Grey Kangaroo and the Forester Kangaroo. Although a big Eastern Grey male typically weighs around 66 kg (145 lb.) and stands almost 2 m (6 ft.) tall, the scientific name, Macropus giganteus (gigantic large-foot), is misleading, as the Red Kangaroo of the semi-arid inland is larger.
Description
The Eastern Grey is easy to recognise: its soft grey coat is distinctive, and it is usually found in moister, more fertile areas than the Red. Indigenous Australian names include iyirrbir (Uw Oykangand and Uw Olkola) and kucha (Pakanh).
Ecology
Although the Red is better known by reputation, the Eastern Grey is the species most commonly seen in the flesh: few Australians visit the arid interior of the continent, while many live in and around the major cities of the south and east coast, from where it is usually only a short drive to the remaining pockets of near-city bushland where roos can be found without much difficulty. It prefers open grassland with areas of bush for daytime shelter. Like all kangaroos, it is mainly nocturnal and crepuscular, and is mostly seen early in the morning, or as the light starts to fade in the evening.
In more remote areas, the Eastern Grey occurs in great numbers, and if left unchecked reaches plague proportions. From time to time shooters are employed to reduce its numbers, almost always to the accompaniment of a public outcry. Given the very limited amount of fodder in dry years, however, the only other choice is starvation.
Speed
The Eastern Grey Kangaroo can travel very fast over land. The highest ever recorded speed of any kangaroo was 64 kilometres per hour (40 mph) set by a large female Eastern Grey Kangaroo.
Status
It is often said that kangaroo populations have increased significantly since the European colonisation of Australia because of the increased areas of grassland (as opposed to forest), the reduction in Dingo numbers, and the availability of artificial watering holes. The current estimated population of the species numbers two million. Due to this, the Eastern Grey has begun to be culled in some parts of Australia
While the Eastern Grey remains common, there are vast areas of country from which it has been exterminated (in general, it avoids humans), and most of the more fertile districts now carry crops or exotic pasture grasses which kangaroos tend not to eat. (One of the easiest ways to find kangaroos is to look for patches of remnant native grassland.)
From Wikipedia, the free encyclopedia
Western Grey Kangaroo
The Western Grey Kangaroo (Macropus fuliginosus) is a large and very common macropod, found across almost the entire southern part of Australia, from just south of Shark Bay to coastal South Australia, western Victoria, and the entire Murray-Darling Basin in New South Wales and Queensland. The subspecies on Kangaroo Island, South Australia, is known as the Kangaroo Island Kangaroo.
Description
The Western Grey Kangaroo is one of the largest kangaroos. It weighs 28-54 kg and its length is 0.84-1.1m with a 80-100 cm tail, standing approximately 1.3m tall. It exhibits sexual dimorphism with the male up to twice the size of female. It has thick, coarse fur with colour ranging from pale greyish-brown to chocolate-brown; its throat, chest and belly have a paler colour. It feeds at night, mainly on grasses but also on leafy shrubs and low trees. It has a nickname Stinker because mature males have a distinctive curry-like odour.
The kangaroo lives in groups of up to 15. The males compete for females during the breeding season. During these "boxing" contests, they would lock arms and try to push each other over. Usually, only the dominant male in the group mates. The gestation period is 30-31 days, after which, the baby Joey attaches to the teat in the pouch for 130-150 days.
Classification
Long known to the Aboriginal people of Australia, for Europeans, the Western Grey was the centre of a great deal of sometimes comical taxonomic confusion for almost 200 years. It was first noted by European settlers when the great explorer Matthew Flinders landed on Kangaroo Island in 1802. Flinders shot several for food but assumed that they were Eastern Grey Kangaroos. In 1803 French explorers captured several Kangaroo Island Western Greys and shipped them home to Paris, where they lived in the zoological gardens for some years. Eventually, researchers at the Paris Museum of Natural History recognised that these animals were indeed different and formally described the species as Macropus fuliginosus in 1817. Unfortunately, for reasons that remain unclear, it was described as native to Tasmania.
There the matter rested for over 100 years, and it was not until 1917 that researchers realised that the "Forester Kangaroo" of Tasmania was in fact Macropus giganteus, the same Eastern Grey Kangaroo that was, and still is, widespread in the more fertile south-eastern part of the mainland. By 1971, it was understood that the Kangaroo Island species was the same as the kangaroos of southern Western Australia, and that this population extended through much of the eastern part of the continent as well. For a time, three subspecies were described, two on the mainland and one on Kangaroo Island. Finally, by the early 1990s, the current understanding emerged.
Subspecies
There are two subspecies of the Western Grey: Macropus fuliginosus fuliginosus of Kangaroo Island, and Macropus fuliginosus melanops, which has a range of different forms that intergrade clinally from west to east.
The Western Grey is not found in the tropical north or the fertile south-east of Australia, and the Eastern Grey does not extend beyond the NSW-South Australia border, but the two species are both common in the Murray-Darling Basin area. They never interbreed in the wild, although it has proved possible to produce hybrids between Eastern Grey females and Western Grey males in captivity.
The Western Grey Kangaroo is also referred to as a Black-faced Kangaroo, Mallee Kangaroo or Sooty Kangaroo.
From Wikipedia, the free encyclopedia