Koalas and Eucalyptus Leaves

Koalas and Eucalyptus leaves are inseparable. In fact, the Eucalyptus leaves are the lifeline of the koalas and without them they may not be able to survive. Eucalyptus are the only leaves on which the koalas feed upon and there is hardly any good alternative to them. Both koalas and Eucalyptus leaves are native to Australian natural habitat within the Eastern region. The Eucalyptus leaves are present in great abundance at the Eastern forests of Australia.

Koalas and Eucalyptus leaves are inseparable. They are the only diet of the koalas and luckily they are found in great abundance in the Eastern regions of Australia.

Koalas have thrived and flourished within these eucalyptus forests for the millions of years. Today; koalas are believed to feed on almost 400 different types of eucalyptus species within the region. However; Manna Gums (Eucalyptus family) are the most common of them all and most preferable to the koalas diet as well. Keeping in mind the koalas' reliance on Eucalyptus leaves, any destruction of Eucalyptus will prove out to be the disaster for the koalas very existence on planet earth.

Koalas only Eat Eucalyptus Leaves
Eucalyptus Leaves are the only food which Koalas eat. Without them the koalas can't even survive. Photo courtesy of  

Koalas & Eucalyptus Leaves
Inseperable Koalas' only Diet
Eucalyptus Leaves Eucalyptus Leaves & Koalas
Native to Australia Koalas' Eat
400 Types of Eucalyptus Leaves Koalas' Favorite
Manna Gum Eucalyptus Leaves

Koalas Eat Eucalyptus Leaves.
Koalas favorite and only food is Eucalyptus. They are always dependent on Eucalyptus leaves throughout their lives. This picture belongs to 

Let's break down the nutritional values and compounds which the eucalyptus leaves offer for the koalas as a diet. Eucalyptus leaves contain oodles of compounds which include water, proteins, cyanide compounds, tannins, fiber and scented oils etc. Some of these compounds are essential for the koalas while the others do seem to be toxic and poisonous. The presence of the water is one of the most essential compounds for the koalas and it is significantly present within the Eucalyptus leaves i.e., more than 61%.

Eucalyptus leaves contain oodles of compounds for the koalas. These compounds include water, fiber, tannins, proteins, cyanide compounds and scented oils.

Its significant presence allows the koalas to avoid drinking water from the waterholes and fulfill all their water requirements from the leaves. Other compounds such as proteins and fibers within the leaves offer nutrition and energy for the koalas while the remaining compounds are highly toxic and are of no use for the koalas but they still consume them.

Eucalyptus Leaves which koalas eat contain water and cyanide compounds
The Eucalyptus leaves which the koalas eat comprise of a lot of compounds such as water, proteins, fibers, cyanide compounds and scented oils etc. Photo courtesy of  

Eucalyptus Breakdown
Nutritional Compounds Water in Leaves
Koalas' Source of Water Fiber & Proteins
Koalas' Source of Energy Cyanide Compounds
Poisonous Scented Oils
Toxic

Koalas prefer different kinds of Eucalyptus leaves.
Koalas prefer different kinds of Eucalyptus leaves. But Koalas in general are very selective in terms of their Eucalyptus leaves' preferences. This picture belongs to  

As mentioned earlier; the Eucalyptus leaves contain highly poisonous and toxic compounds within them and yet still koalas prefer to eat Eucalyptus leaves as part of their diet. Even the cyanide compounds within the Eucalyptus leaves can be extracted to produce the pure cyanide poison that can kill anyone. Surprisingly, these poisons and toxic compounds within the Eucalyptus leaves are not dangerous and life-threatening for the koalas.

Eucalyptus leaves are poisonous for almost all the other herbivores but surprisingly not for the koalas as they eat them on the daily basis.

Majority of other herbivores are unable to feed on Eucalyptus leaves. If they consume these leaves they may soon get sick or die within the days if not moments. On the other hand; koalas eat these toxic and poisonous leaves on the daily basis and they seem to extract nutrition from them which is truly an astonishing development for the researchers.

Eucalyptus leaves which koalas eat are highly poisonous and toxic
The Eucalyptus leaves which the koalas eat are highly toxic and poisonous. A normal herbivore cannot survive on an Eucalyptus diet. Photo courtesy of  

Koalas
Good Sense of Smell Koalas Prefer
Fresh Eucalyptus Leaves Fresh Eucalyptus Leaves
High in Nitrogen Fresh Eucalyptus Leaves
More Water Contents Fresh Eucalyptus Leaves
High Nutrition for Koalas Koalas also Identify
Extremely Poisonous Eucalyptus Leaves

Koalas fulfill their water requirements through Eucalyptus leaves.
Koalas fulfill their water requirements through Eucalyptus leaves. Eucalyptus leaves comprise of 55% water on average. This Picture belongs to  

Koalas have developed a good sense of smell for choosing the Eucalyptus leaves as part of their diet. Koalas can easily differentiate fresh Eucalyptus leaves from the other ones and mostly prefer the fresh Eucalyptus leaves. They smell nitrogen within the leaves and differentiate the fresh ones from the non-fresh ones, as fresh leaves contain more levels of nitrogen.

Koalas have developed a good sense of smell which allows them to have the best selection of Eucalyptus leaves for their diet.

These fresh leaves contain high source of water and energy levels as compared to the older (adult) leaves. Similarly; in some seasons when the toxicity and poison levels are high within the Eucalyptus leaves, the koalas can easily be able to identify them and avoid them as well.

Koalas have good sense of smell which allows them to select fresh leaves.
Koalas have a good sense of smell which allows them to differentiate the fresh leaves from the others. Photo courtesy of  

Koalas
Good Sense of Smell Koalas Prefer
Fresh Eucalyptus Leaves Fresh Eucalyptus Leaves
High in Nitrogen Fresh Eucalyptus Leaves
More Water Contents Fresh Eucalyptus Leaves
High Nutrition for Koalas Koalas also Identify
Extremely Poisonous Eucalyptus Leaves

Koalas fulfill their protein requirements through Eucalyptus leaves.
Koalas fulfill their protein requirements through the Eucalyptus Leaves. Eucalyptus leaves comprise of 4% proteins. This picture belongs to 

Koalas usually consume around 200 to 400 grams of Eucalyptus leaves per day which is not much. Furthermore; this consumption is very little as compared to the other herbivore animals' consumption when compared with their body mass. As a matter of fact, the koalas have limited amount of body energy. This is also one of the basic reasons that the koalas sleep more than 20 hours (in some cases 22 hours) per day, as it allows them to retain and conserve their body energy. But there is another valuable reason to explain about the little Eucalyptus consumption of the koalas which is related to the fiber contents within the Eucalyptus foliage.

Koalas only consume around 200 to 400 grams of Eucalyptus leaves per day because of the high fiber contents within Eucalyptus leaves.

Eucalyptus leaves have high fiber contents, therefore; even after consuming little amounts, the stomach of the koalas gets full and they need to digest it which takes a lot of time. According to the estimates, Eucalyptus fiber is 6 times more fibrous and less caloric than the normal bread fiber. Therefore; high fiber contents within the Eucalyptus leaves allow the koalas to eat less Eucalyptus and sleep more to digest them to extract energy.

Koalas' Eucalyptus Leaves Consumption
Koalas consume around 200 to 400 grams of eucalyptus leaves per day. Photo courtesy of  

Koalas' Eucalyptus Consumption
Very Little Daily Consumption
200 to 400 Grams per Day High Fiber
Less Consumption Eucalyptus Fiber
6 times of Bread Fiber High Fiber Digestion
Takes Time Eucalyptus Fiber Energy
Very Little

Koalas also consume cyanide compounds while eating Eucalyptus leaves.
Koalas prefer to eat Eucalyptus leaves which are also enriched with the Cyanide Compounds as well. However, Koalas have strong immune system and specialized liver, that helps them against the life-threatening impact of the Cyanide Compounds. This picture belongs to 

If the Eucalyptus leaves are very high in poisons and toxic substances then how is it possible that an animal like koala digest them and maintains a normal lifestyle? Are the Koalas immune to the Eucalyptus toxics and poisons? Absolutely so! Whereas; the precise answer to the first question is the presence of specialized digestive and intestinal system within the koalas which helps them to extract all the nutrients and energy from the leaves and excrete the poisons and toxic substances out of their bodies.

Koalas have a very specialized digestive and intestinal system which extracts all the nutrients through the fermentation of the Eucalyptus leaves.

These nutrients are extracted through fermentation of the Eucalyptus leaves while large and small intestinal cells of the Koalas extract and absorb these nutrients to produce energy. Since koalas have very small brain and liver, therefore; their energy consumption and energy loss are a lot less as compared to the other herbivore animals. Some researcher have also argued that fermentation also produces alcohols in koalas and that's why they are lazy and sleepy but no significant findings have been yet been made about such claims.

Eucalyptus Digestion of Koalas
Specialized Digestive System Eucalyptus Digestion of Other Herbivores
Not Possible and they may Die Koalas Digest Ecualyptus
Through Fermentation Fermentation Process in Koalas
Slow Digestive Energy
Very Less

Koalas efficiently digest the Eucalyptus leaves
Koalas have a very specialized digestive and intestinal system which allows them to digest the poisonous and toxic Eucalyptus leaves. Photo courtesy of  

Only the properly chewed Eucalyptus leaves help koalas to gain energy and nutrition while digestion. Proper chewing of leaves improves the fermentation process. Poorly chewed leaves reduces the efficiency of the fermentation process and thus less nutrition and energy is extracted by the koalas. When the koalas become old their tooth start to decay.

Older koalas lose their teeth because of tooth decaying over the time. This reduces fermentation of eucalyptus while digestion and thus the koalas die because of nutritional failure and starvation.

Tooth decaying makes an adverse impact on the chewing of the Eucalyptus leaves and therefore; less nutritional values and even energy is extracted by the older koalas. Consequently; they become weaker and weaker and reach a certain point in their lives where they are believed to face death because of nutritional failures and starvation.

Proper Chewing
Efficient Fermentation Process Poor Chewing
Poor Fermentation Older Koalas Face
Tooth Decaying Older Koalas' Chewing
Very Poor Older Koalas' Death
Starvation & Nutritional Failures

Koalas properly chew the Eucalyptus leaves to improve the fermentation process.
Koalas have to chew the Eucalyptus leaves properly to improve the fermentation process. Older koalas can't chew properly and they die becuase of nutritional failure and starvation. Photo courtesy of  

Since; the koalas are only dependent on the Eucalyptus leaves for their diet, therefore; any habitat loss of the Eucalyptus trees can be a big disaster for them. Eucalyptus have thrived within the Eastern Australian region for the millions of years and they are known to be drought resistant as well. Therefore; naturally there is no threat to the habitat loss of the Eucalyptus leaves for the koalas. However; rapid urban development within Eastern Australian regions is severely impacting the habitat loss for the koalas.

Habitat loss of the Eucalyptus trees means death for the koalas and a possible extinction as well. Therefore; conservation of the Eucalyptuses is the only way forward to save the koalas.

Thousands of trees are cut for the purpose of timber or housing societies while koalas are forced to either leave or die of starvation or get hunted. Even though the Australian Governments have taken key steps to ensure the koalas' habitat yet still, the Eucalyptus habitat is continuously threatened for the koalas on the daily basis.

Habitat loss of the Eucalyptus leaves means a death for the Koalas.
Eucalyptus leaves are very important for the koalas. Any habitat loss of the Eucalyptus leaves means a death for the koalas and a possible extinction as well. Photo courtesy of