Kangaroos are well known for their pouch, which can be described through the term “marsupial”, a distinctive trait found between members of the infraclass Marsupialia. These professional hoppers belong to the family Macropodidae that literally means “big foot”.
In 2015, it was estimated that this national symbol thrived with approximately 44 million kangaroos on the entire continent. There are around 60 species of kangaroo, six of which that are large mammals.
All species of kangaroos are strict herbivores. As one would imagine, the different climates and biomes alter the diet of these species, each having to face their own set of challenges in the wild Outback.
What Do Kangaroos Eat in the Wild?
The diet of a kangaroo found in the wild depends on the species and where it can be found amongst various habitats of Australia. In order to thoroughly understand the diet of kangaroos as a mammal, we must evaluate the four most widely distributed individuals.
Eastern Grey Kangaroo
The Eastern Grey Kangaroo (Macropus giganteus) is found within Eastern and Southern Australia, and the most widespread of all currently discovered kangaroo species. They dwell amongst the wetter biomes of the Outback such as the forested coastal areas, open grasslands, and open woodlands.
Another name given to these marsupials is the “Great Grey Kangaroo” for its large body mass of 145 pounds or 66 kilograms. To avoid becoming overheated, these animals are mainly nocturnal and crepuscular, foraging in the early mornings and as the sun begins to fade.
This species of kangaroo is an herbivorous grazer with very specific dietary preferences. The Eastern Grey Kangaroo consumes a variety of plants but will favor grasses when available.
In the woodlands, this species will munch on shrubs and fungi. For those living among the forested coastal regions of Australia, this kangaroo expands its diet to anything that the trees supply. This ranges from leaves, fallen fruit, bark, seeds, flowers and sap.
Western Grey Kangaroo
Living in the open forests, coastal heathlands, scrublands and woodlands of Southern Australia is the Western Grey Kangaroo (Macropus fuliginosus). This region of the Down Under experiences heavy rainfalls that can exceed 250 millimeters in a year.
This species stands tall, weighing approximately 60 to 120 pounds, or 30 to 55 kilograms. It can be difficult to tell apart from its sibling species, the Eastern Grey Kangaroo, but is recognizable for its darker coat, most noticeably around the head and sometimes on the elbow. Like the Eastern species, the Western Grey Kangaroo forages at night when heat exhaustion is not an issue.
As all kangaroo species, this animal is strictly herbivorous. Due to the habitat that it occupies, they feed mostly on grasses, herbs, and leaves. In fact, the Western Grey Kangaroo has an incredibly high tolerance when it comes to consuming plant toxins. Those found in the forests forage for leaves and tree bark.
Living in an area with plentiful rainfall is a perk that other species do not have the luxury of. The Western Grey Kangaroo is presented with new growth for the majority of the year, supplying a large quantity of grasses and plants.
The Red Kangaroo (Macropus rufus) is the king of all kangaroos, being the largest of the species. It has also earned the record of the largest terrestrial, or land-dwelling mammal that is native to Australia. On average, this species stands at about 5 feet tall, or 1.5 meters, and weighs anywhere from 40 to 200 pounds, or 18 to 90 kilograms.
The Latin name “rufus” refers to the iconic red fur that the males portray. Interestingly, the females are called “blue flyers” for their blue-grey tinted coats. This species is widely distributed across the mainland of Australia, avoiding the more fertile regions such as the south, east, and northern coastlines. It prefers the semi-arid biomes, which include the Outback’s plains, grasslands, woodlands and open forests.
This kangaroo species is well adapted to living in arid biomes, using its herbivorous preferences to find available food. The Red Kangaroo eats a large quantity of green vegetation, most of which are fresh grasses and forbs. Scientists conducted a study in Central Australia to determine just how much of grass was consumed by these marsupials. They found that a staggering 75 to 95 percent of their diet consisted of green grass. Taking this into consideration, it is evident that Red Kangaroos rely on grasses and other vegetation more so than other species, perhaps due to the extreme arid environments.
The Antilopine Kangaroo (Macropus antilopus) has been debated by scientists for years, some believing that it should be called a different species altogether. A wallaroo is a closely related species Macropus, which is the genus that encases all kangaroos. It is between the height and weight of a kangaroo and wallaby, another marsupial in the same genus. Combining “kangaroo” and “wallaby”, biologists coined the term “wallaroo”.
The Antilopine Kangaroo is sometimes called the Antilopine Wallaroo, but has been called the exception for the remarkable characteristics to the two grey kangaroo species.
This species is smaller than the Red Kangaroo, weighing around 154 pounds, or 70 kilograms for the males. The root of its species “Antilopus” translates to “antelope”, a name given for its speed. The Antilopine Kangaroo is more slender than its fellow sibling species.
This marsupial lives in the extreme northern habitats of Australia involving the monsoonal eucalyptus woodlands. It is the only kangaroo species to live entirely in the tropics.
This marsupial is herbivorous, feeding mainly on grass throughout the day. They prefer short grass, even traveling to areas where tall grass has been reduced by fires. If able, this species will seek out Low Tussock Grass as its primary source of food.
Does a Kangaroo’s Diet Change Based on the Season?
Living on a continent that can have dry seasons without water for weeks is a challenge that most wild animals couldn’t overcome. The kangaroo has learned to combat this problem. The Red Kangaroo, in particular, is known to forage for green plants during the most arid times of the year.
They are able to find this foliage by staying in the open grasslands and not straying far from watercourses. The dryer seasons also require these animals to gain water from other sources. Vegetation provides kangaroos with a great deal of liquid during these challenging times. A kangaroo can go several days without water, but rely on grass when it is scarce.
What Do Kangaroos Eat in Captivity?
The kangaroo is endemic to Australia, meaning that it cannot be found elsewhere in the wild. This does not mean, however, that they thrive in zoos. The public enjoys seeing creatures that they would not have the chance to see.
It wasn’t until around the mid 1900’s where kangaroos were sent to zoos around the world, one of which was the San Diego Zoo, a place that leads in conservation and education. In 1960, they were gifted their first kangaroo from the Taronga Zoo in Sydney, New South Wales, Australia. But are these mammals given a similar diet to that of their wild relatives?
As for what a kangaroo will eat in captivity, it isn’t all that different from that of those in the wild. Keepers will usually implement a diet specified for grazers through pellets. This is a common zoo food item as it packs in necessary nutrients that animals are unable to consume since held in captivity.
In addition to a regimen of pellets, captive-bred individuals will also be treated with alfalfa hay and garden produce such as carrots, apples, broccoli, and bananas.
Greens are essential, even for a zoo-dwelling kangaroo. Oftentimes, this need is met with dandelion leaves or romaine.
For tree kangaroos, leafy browse is included, such as willow and maple branches or bamboo. It is essential to provide kangaroos with a variety of foliage and vegetation to graze upon as it demonstrates visitors with natural behaviors that would be seen in the wild.
How Do Kangaroos Forage?
Kangaroos are a grazer, finding grasses and other vegetation in the continent of Australia. Due to their feeding habits, these marsupials have highly developed teeth that are rarely found in other mammals.
The kangaroo’s incisors are sharp enough to cut grass close to the ground while its molars are designed to grind up foliage. In addition to the specialized teeth, these animals have a wider bite since their lower jaw is not joined or fused. They can then intake a larger quantity of grass, eating at a faster pace.
If you were told that kangaroos are similar to cows, you might not believe it. Interestingly, this is not a falsehood. These animals will grind their food until it is moist enough to be swallowed whole. It is then regurgitated at a later time in a form of cud, where it is chewed again and completely swallowed. This is exactly what is done in cows. This allows the food to be digested more thoroughly.
The Digestive System of a Kangaroo
The food that is consumed by a kangaroo is high in fiber. In most mammals, this would be a nightmare to digest, but not for these marsupials. With a uniquely designed stomach, the kangaroo is able to break down plants and absorb more of the nutrition so that it isn’t wasted. This is accomplished through a stomach with multiple chambers. Inside the stomach is a bacterium that allows enzymes and plant cell walls to be broken down. With the constant intake of grasses and other vegetation, this digestive system is key to surviving the extreme conditions of Australia.
How Does a Baby Kangaroo Get Food?
Perhaps you’ve heard that an infant kangaroo is referred to as a “joey”. These babies are born blind, hairless, and not fully developed. Instead, they survive off of the milk supplied by their mother for up to nine months.
Interestingly, a female can have up to three joeys by giving a teat to each of her babies. Once old enough, a joey will exit the pouch, learning how to thrive on an herbivorous diet. It typically takes about ten months for a Red Kangaroo, and up to 18 months for a grey kangaroo species.
How Long Do Kangaroos Live?
The longevity of a kangaroo depends on a multitude of factors including if it is in the wild and what natural predators are present. The difference in species can also have an impact on how long a kangaroo will live.
As for the Eastern Grey Kangaroo and the Western Grey Kangaroo, these species usually live from 8 to 12 months in the wild and up to 20 years in captivity. They are shorter and heavier than other species, making them not live as long as their close relatives. The Red Kangaroo is arguably one of the most well-adapted marsupial species. Scientists have recorded that the average life span of a Red Kangaroo in both the wild and in captivity is about 20 years, oftentimes exceeding 23 years. The Antilopine Kangaroo does not fend as well in the wild, averaging at around six years. It usually does better in captivity, lasting 20 years or more.
Pests of Australia
Every country has its own specific unwanted pest. For Australia, it is the kangaroo. If you were to travel to the continent, you’d see why. Because these animals are so well adapted to the harsh biomes, they have exploded in numbers. In fact, studies have shown that there are just about twice as many kangaroos as there are people in Australia. This heavily impacts the farmers and ranchers, especially in the dryer months where droughts are almost constant. The land divided up for cattle and sheep are quickly overpopulated with these so-called pests. Although the kangaroo is a national emblem for the continent, Australia has not been delighted in the sheer numbers of kangaroos depleting grasses.
How Fast Can They Travel?
One remarkable feature about the kangaroo are their large legs that act as springboards. These marsupials are the only large animals to use hopping as a way of getting around. The king of kangaroos, the Red Kangaroo, usually hops around at about 12 to 16 miles per hour, or 20 to 25 kilometers per hour. If putting more effort into it, they can cover a short distance at 43 miles per hour, or 70 kilometers per hour. But how exactly do they use those long legs?
The act of hopping seems tricky for an animal of large size, yet kangaroos are able to do it effortlessly. As you would assume, the tail does have a part in it. This body part allows the animal to balance, acting as a counterweight while pushing the ‘roo forward. With the use of their front legs, they push off at high speeds. They keep this trajectory through the energy that is stored in their tendons. These tendons act as a rubber band, making the act of hopping a breeze.
When considering all of the exotic and endemic animals to inhabit the Down Under, hopefully, you will consider the incredibly adaptive marsupial. With effortless hopping, a pouch for their joeys, and a variety of species, it seems to the fitting emblem of Australia. The herbivorous diet of a kangaroo is filled with mostly grasses, shrubs, leaves and even fungus. What’s not to love about the modern day ‘roo?