Kangaroos are a super cute, fun but sometimes aggressive marsupial that is endemic to Australia which many people love. They’re very mobile and are instantaneously recognized by their hopping method of locomotion which is facilitated by the immense strength in their hind legs and supported by a muscular tail.
The origin of the word kangaroo can be found through the aboriginal language called Guugu Yimithirr. They referred to the grey kangaroo varieties as Kanguru which was then recorded in the diary of the English naturalist Sir Joseph Banks.
The Australian mainland is a huge landmass which features many different environments and habitats. This, of course, promotes a booming biodiversity of which is quite unique to Australia and the surrounding islands that make up the continent; an example of this is marsupials.
When it comes to asking about kangaroo diet there are some considerations to make beforehand. Kangaroos are not just the large hoppers you see grazing in Australian plains but are a diverse family of creatures which share many similarities but have minor differences which separate them as species.
Meet the Macropods (A brief overview of roo taxonomy)
Kangaroo is used as an umbrella term to encompass similar species which all belong to the Macropodidae family. This is a group of remarkable marsupials that share similarities in that they are all herbivores, have powerful, elongated hind legs, typically short front legs and a strong tail.
The Macropodidae family can be further divided into different groups called genera and they include your famous and not so famous kangaroo relatives such as wallabies, wallaroos, kangaroos and tree kangaroos.
The whole family derives from an ancestor whom they share with another family of marsupials which contains nocturnal tree-dwelling animals such as possums and cuscuses. These ancestors lived in a very different Australia than what we see today; covered in a dense tropical rainforest as opposed to prevalent grasslands.
As the climate changed over time, Australia became a drier place which an increase in plains and deserts. This resulted in the evolutionary development of digestive systems which are more efficient with grasses and tough plants and an increase in size and mobility to cover larger areas.
Species of Kangaroo
Digressing from the complicated topic of taxonomy, there are three species of the large hoppers that are considered actual kangaroos within this genus barring the antilopine kangaroo which is defined as a wallaroo. They all belong to the Macropus genus and all have differences between each other as they have adapted to various habitats which contain different plants.
This means that to answer your question on the diet of kangaroos we will need to get an understanding of the four species, their habitats and the plant life which exists there.
The Red Kangaroo (Genus: Marcopus, Species: rufus)
M. rufus, or simply the “red kangaroo”, is not only the largest species of kangaroo but also the largest marsupial found today.
Adult males can range between 1.3 and 1.6 meters in height (without including the tail) and typically range between 55 and 90Kg. On the other hand, females are much smaller with a maximum average height range of between 0.85 and 1.05 meters and weighing in at a range between 18 and 45Kg, nearly half the size of males!
Despite their name, their fur color can vary and it depends on their sex. Males have the namesake red/brown fur which fades into a lighter yellow/brown on the underside of their body, tail and around the limbs.
Females, however, are normally not as vibrant, normally sporting a blue/grey coat with lighter grey areas. There is an exception though, as females that inhabit arid areas have coloration similar to the males. Even though they may sometimes be similar in color to the eastern greys, they are easily distinguished by the unique black and white marking on their face.
Their geographical reach in Australia is fairly vast; encompassing most of central and western Australia, avoiding rich fertile, subtropical and coastal areas. They prefer open grassland areas with a sporadic presence of trees which they use to hang out in the shade.
The Red Kangaroo Diet
Due to their adaptations, they’re very flexible when it comes to survival in dry, arid environments; with a biology geared towards water conservation and extracting nutrition from plants which, well, aren’t very nutritious.
They prefer green vegetation as the main constituent of their diet but can still live on plants that are wilting during the hot seasons. A kangaroos day is mostly made up of grazing on grasses, the red kangaroo in particular likes the grass species known as Eragrostis setifolia also sweetly referred to as love grass as it stays green throughout the dry season.
When the grass they love (love grass, get it?) is not available they do like to have a go on shrubs and some particular plants which belong to the Chenopodiaceae family such as Bassia diacantha but avoid others in the family.
The Western Grey Kangaroo (Genus: Macropus, Species: fuliginosus)
M. fuliginosus, western grey kangaroo, black-faced kangaroo, sooty kangaroo and mallee kangaroo are all names that these roos go by.
They are found in open grasslands, forests, and woodlands throughout the south and parts of West Australia and are split into two distinctive subspecies. Macropus fuliginosus fuliginosusis is the subspecies found on an island to the south of Australia dubbed kangaroo island and were initially thought to be a completely separate species to Macropus fuliginosus melanops found on the mainland.
They sport a lovely fur coat which comes in dark or chocolate shades of brown with large pointy ears that are distinguished by the white fur inline. Just like their red counterparts, their coloration fades to lighter shades on the underside of their limbs and body but the tail of this species is tipped with black.
The Western Grey Kangaroo Diet
Western greys, similar to other species of kangaroo, are grazers and feed on varieties of foliage available in their habitats. This is usually a mix of grasses, shrubs, leaves and other foliage.
The Eastern Grey Kangaroo (Genus: Macropus, Species: giganteus)
Don’t let their scientific name fool you; M. giganteus is not the largest species of kangaroo as this title belongs to the red roos but their name is actually referring to their trademark large feet. Although not the largest species of kangaroo, they do have a stockier build than their relatives with adult males typically weighing in between 40 and 66Kgs and females between 17 and 40Kgs.
They are quite unassuming in appearance in comparison to other kangaroo species with fluffy light grey fur and seemingly wider eyes. Just like the westies, the east greys have fine fur around their head and muzzle giving it a much more rounded appearance. A major difference between the two is that the coat of M. giganteus is usually composed of lighter shades of greys and whites.
This species loves open plains but also live in more fertile forested areas. They are also far more adaptable and so are encountered more frequently by humans due to their tendency to live in the wilds and by cities on the south and east side. They can also be found in woodlands, on the coasts, mountains and even sub-tropics.
The Eastern Grey Kangaroo Diet
Despite being found in many diverse ecosystems, the eastern grey is a more predominant grass grazer than their red cousins, rarely including shrubs or other foliage into their diet. This will actually be due to their environmental flexibility allowing them to access moist, fertile lands with plenty of delicious green grass.
An Advantage of Grazers – Rumination
All herbivorous marsupials are similar to but not a part of the group of animals referred to as ruminants; that is animals such as cattle which have multiple stomachs, chew the cud and have a huge variety of symbiotic bacteria in their G.I tract. The bacteria help to extract nutrients from otherwise low nutrition foods such as grasses and foliage, an excellent adaptation to allow the consumption of a low competition food source.
It was mentioned earlier that kangaroos belonged to a family of similar marsupials called Macropodidae and unlike other marsupials (such as koalas and wombats), these animals are foregut fermenters as opposed to hindgut fermenters. This means the bacterial stage of digestion is predominant in the front stomach.
- Kangaroos emerged from a common arboreal (tree-dwelling) marsupial ancestor who evolved to become terrestrial grazers.
- A key adaptation that allows this is the ruminant style digestive system allowing them to feed on a variety of grasses, shrubs and other foliage.
- The specific diet of a kangaroo species is highly dependent on the habit you find them and the plants that exist there.