Why Do Ostriches Eat Stone? (Explained)

by Alex Kountry
Updated on

Ostriches Eat Stones because of their lack of teeth. After eating they will need to digest the food, but with the lack of teeth this process becomes difficult because for the food to digest first of all needs to be ground. This is where eating the stone comes from.

The ostrich swallows Sharp pebbles and grit then holds these rocks in gizzards.

The gizzards are a muscular part of their stomach, it contracts and grinds the stones against each other and also against the food swallowed by the birds, the stones in turn grind down the food then pass it off for digestion.

The rocks are essentially used by the Ostriches to chew the food in the gizzards,

The rocks will not only grind against the food but also against each other, over time the rocks become smooth like pebbles and the birds will no longer need them.

If it comes to that, the ostrich will have to vomit out the rocks then swallow another one to repeat the whole process all over again.

How Do Ostriches Chew and Grind Their Food?

Why Do Ostriches Eat Stone

Ostriches chew and grind their food by eating stones and small pebbles.

Since they do not have teeth to chew the food, the stone helps them by grinding the food together to aid them in digesting the food eaten.

The ostriches are ultimately omnivores but most of their food is the plants, some plants that ostriches eat are the flowers, berries, leaves, and shrubs of bushes, succulents, sprouts, Nuts, seeds, etc.

Since they are omnivore animals, they can also eat food like insects, small tortoises, lizards, small rodents, frogs, etc.

They also scavenge body of large animals killed by predators like lions etc.

They swallow stones and sand that become gastroliths, ostriches are fond of doing this both in the wild or in captivity.

The Ostriches have no gall or crop, the crop helps in storing food until it is ready to be digested.

The stone and small sand however help in grinding all the food eaten by the ostriches for the food to get easily digested.

Here is an article I wrote on how do ostriches protect themselves

Can Ostrich Digest Stones?

Since food digestion is difficult for ostriches without them having teeth, they tend to swallow stone and sand to help with this process.

Ostriches are a part of the gastrolith system, this translates to stomach stones, they swallow stones, pebbles, rocks, and other scratches then have them stored in a muscular part of their stomach known as gizzards.

An adult ostrich carries about 2.2pounds in its gizzards which is the ostrich’s second stomach, since they most likely do not have teeth to grind the food, they eat stones to help them with the digestion process by grinding the food in the gizzards.

 What Is The Digestive Process for Ostriches?

The ostrich has a very unique digestive process, like humans, the ostriches are omnivores meaning they can comfortably eat both plants and animals,

This all depends on what is available in their habitats for them to eat,

it is also dependent on what time of year it is as this determines the type of food resources that may be available, ostriches are also Nomadic, meaning they will move from one place to the other in search of food.

Some types of food that ostriches consume are seeds, shrubs, bushes, and leaves. Ostriches most times are considered grazers hence when wandering around they feed on these types of nutrients.

Some other types of nutrients that they eat that are not strictly plants are the invertebrates like insects, small vertebrates like lizards, and rodents.

The food is ingested into their body by using their beaks, from there the food is stored at the top of their throats,

They place is called crop in most animals but the ostriches do not have crops, in the crop’s place is the granular stomach called the proventricular in ostriches.

The proventricular is a primary storage organ that secretes pepsin and acids.

When the food is amassed enough in this glandular stomach, the food slides down their long throats into a place called the ventriculus.

Due to their unique diet, the ostriches have a very distinct digestive system.

The ostrich digestive system contains a very tough long intestine that when stretched out is 45 feet.

Within the ostrich’s stomach lies the grit rocks and other materials that will aid the ostriches in breaking down the food eaten before the food enters the small intestine.

To ensure they can break down what they have eaten, the ostriches in addition will need to eat stones or rocks.

From eating food, the ostrich ingests water from the plants, ideally, an ostrich will like to have 1 to 2 gallons of water daily,

But they can survive several days without water due to the complex nature of their system that comes from being so large.

Depending on the season an ostrich can overcome climate change or a change in food availability by eating what is available, but if they can’t find food within the area they have found themselves, they do not mind moving to another area in search of food.

An ostrich needs to have the required nutrients so it will be able to pass its genes through reproduction and continue with evolving the ostrich species.

In summary, the stones swallowed by the ostriches are primarily used to help them in grinding down the various foods they consume to make the food easily digestible.

Also check out this article I wrote on how do ostriches survive

What Else Do Ostriches Eat?

Although an Ostrich will eat roots, flowers, and fruits mostly since they are mainly grazers, it may also take insects, lizards, small tortoises.

The baby ostrich after hatching initially will feed on yolk from the egg yolk for two weeks before following their parent’s footsteps in learning how to eat.

Farm-based ostriches on the other hand are fed different varieties of commercially available feeds that differ significantly depending on the part of the world the ostrich is being raised,

Thanks to their flexible eating habits, as long as all the required nutrients are made available in their food, the diets can be appropriate for them.

Feeding baby ostriches is quite different from feeding adult ostriches, there is no acceptable scientific method in feeding a baby ostrich,

This leads to different producers of ostriches employing different methods as to what is suitable for a baby ostrich to feed on.

Some producers refrain from feeding the chicks any food or water for 6 to 8 days after birth, while others prefer to give them food and water immediately after hatching.

If you are raising ostriches for commercial purposes, you must make sure they are receiving the right amount of nutrients to enable them to develop properly.

The ostrich breeder feeds should contain the following nutrients to avoid the effects of vitamin and minerals deficiencies in the Ostriches.

These nutrients are Vitamin A, D, and E, Thiamin B1, Riboflavin B2, Folic acids amongst others.


Ostriches are a very particular type of bird, they are the largest birds with interesting feeding habits and mating processes.

An ostrich is primarily a grazer and will eat trees, grasses, shrubs just about anything, just like humans, they are omnivores, meaning they can eat anything ranging from plants to insects and small vertebrates like rodents.

The ostrich does not have teeth that will help them in grinding and breaking down food eaten for digestion, what they do is swallow stones and sand that will aid them in the grinding process.

Photo of author

About the author

Alex Kountry

Alex Kountry is the founder of HayFarmGuy and has been a backyard farmer for over 10 years. Since then he has decided to write helpful articles that will help you become a better backyard farmer and know what to do. He also loves to play tennis and read books


HayFarmGuy - Get Info About Farm Animals in Your Inbox