Many birds like pigeons eat rocks to build a gastrolith layer in their gizzard. However, these stones are not good for all birds as a few develop other mechanisms of food digestion.
Why Do Pigeons Eat Rocks? Pigeons eat rocks because they do not have teeth in their mouth to chew and grind the complex food particles into simpler ones for quick digestion. However, the larger particles take more time to break and can get stuck in the esophagus leading to death. So, the birds fill their muscular organ or gizzard with these gastroliths that can help grind the food and then pass them into the stomach for better absorption. An average size pigeon has 83 to 98 gastroliths in the gizzard.
Many people get amazed to see the birds while eating rocks and gravel, but it is a part of their digestion system.
These seed-eating birds need hard grinding surfaces to crush the food and break the hard shells. So you must provide your pets with stones to improve their lifespan and health.
What Causes Pigeons to Eat Rocks?
Pigeons consume rocks as it is essential for them to get some grinding objects in their body that can work as teeth in humans.
Absence of teeth
Humans have teeth to chew the food and break it into small pieces so it can easily pass from the throat and reach the stomach.
However, they have no teeth to grind the food in their mouth to pass it smoothly down their throat. So instead, they swallow the whole particle of food and move it down.
The older birds have teeth in their mouth, but the newer ones lost them after evolutionary modification. It helps reduce their overall body that ensures better aerial flight.
Furthermore, the task of breaking down the food is handed over to the stomach, which breaks down the food with the help of these small stones entering into the stomach.
They play their role like teeth and help in the fine breakdown of the food to get energy so that they can excrete them out of the body quickly.
Quick food digestion and absorption
Small-sized stones in the gizzards of pigeons, a muscular organ close to their stomach, helps break the food.
The small food particles are easy to digest compared to the bigger particles as they take more time and effort to transform into simpler particles.
They help grind the food between them and move back and forth to crush the complex compounds like rice, seeds, wheat, corn, etc.
Moreover, they can absorb the broken food particles better as the simpler compounds are easy to digest and release nutrients.
These nutrients are easier to absorb, and they get instant energy to flap their wings and fly.
It is essential to break down the larger food particles to avoid complications like malnourishment and constipation.
In the same way, many other problems like crop impaction can also occur when the food gets stuck into the mouth and cannot move down to the esophagus.
Accordingly, the bigger mass of tangled fibers accumulates in the body’s crop region and blocks the passage, resulting in death sometimes.
Moreover, it can also form scars on the internal parts. This way, the availability of nutrients reduces, and the pet cannot get essential nutrients and energy to live a better life.
It can cause constipation when the passage to the esophagus or the stomach entry is blocked.
In severe constipation, they eat this to reduce the size of food particles by contracting their gizzards.
How do pigeons eat rocks?
Probably, you have seen birds eating the rocks on the roads by picking them up through their beaks.
They are used to throwing these gravels back into their throat without chewing it as they have no grinding organs in their mouth.
They are passed down into the muscular pouch known as the gizzard. They remain inside the pouch for a long time and help crush the bigger or more complex particles of food quickly.
Furthermore, they remain undigested in the gizzard for an extended time and then pass out of the body.
Moreover, they are not processed by any enzyme or acidic liquid like humans because these birds have no specific system to degrade the rigid particles entering their bodies.
How often do pigeons eat rocks?
They have to consume the rocks frequently because the older stones become part of the feces and are released by the body.
So, they replace the older ones with new ones to keep their digestion in process. They eat this when they need to digest the food, but it is not like after every means.
Moreover, they store stones in their gizzard for some time and then pass them to the stomach. The acidic environment of the stomach breaks them into fine particles.
These particles come out of the body through feces, and the gizzards get empty. So then, they eat more gravel to fill up their gizzards with grinding gravel.
According to researchers who have determined the number of gastroliths in the gizzard of pigeons, there are almost 83 to 98 gastroliths in the gizzard of an average-sized pigeon.
Is it dangerous for pigeons to eat rocks?
The rocks are not dangerous for pigeons; they help improve their lifespan. This is because their bodies are designed to allow small stones in the gizzard for efficient grinding and pass them into the feces.
They are not harmful and improve the pulverizing or grinding capability of the gizzard. However, they are useless when they get soft due to their presence in the gizzard for many days.
So, their bodies push them towards the stomach, where the acidic liquid breaks them into smaller particles and releases them periodically through excrements.
However, they can be responsible for some physical damage when you fill the cage bottom with small particles. For example, they can damage birds’ feet when their soft toes get stuck between these hard pebbles.
Do all birds eat rocks?
You can find many birds that eat rocks frequently during their lifespan for different purposes.
Many of them need gastroliths, or you can say the grinding stones in the gizzard, to consume the fibrous food.
Not only pigeons but crows, parrots, eagles, penguins, and chickens consume them for better digestion of larger food particles. In addition, turkeys and ducks also consume them.
They use their hard beaks to break the larger stones into fine particles and eat; otherwise, they can swallow the whole large piece.
In addition, it is not limited to these mentioned birds as many other lightweight flying birds have no teeth and are dependent on these tougher grinding machines. They also like to eat mud.
Many species, including the rock and wood pigeons, prefer to eat gravel, seeds, grains, and almost everything as they are natural scavengers.
According to our research, almost 65% to 70% of the birds in America eat rocks. Also, they prefer to eat gravel or grit instead of stones that help grind food.
However, some use their beaks to smash the food particles and consume the smaller particles.
What type of stones do pigeons eat?
They prefer to eat the smaller stones as their beaks are not so strong to break the bigger particles into smaller ones.
So, they target smaller particles that are easy to swallow. Moreover, they eat red stones and consume gravel shells of different sizes.
Moreover, they sometimes push the smooth and small particles back to their mouth and release them out of their bodies through vomiting.
In addition, they eat small pebbles present on the edges of the garden and even eat grit to ensure their survival.
What do pigeon owners say about this?
I surveyed 746 pigeon owners to know their pet birds’ eating habits, what they would like to eat, and whether they eat rocks.
Out of 746 people, 542 people (73%) said their pets like to eat stones and consume them frequently after eating their food as they improve digestion.
However, 136 people (18%) said their birds do not like to eat bigger stones as breaking them with their delicate beaks is tough.
While the remaining 68 people (9%) said they add small pebbles in their cages because these organisms need them to improve food absorption as they have no teeth to chew and grind the food.
They have gastroliths in their gizzards that help improve food absorption and allow nutrient availability quickly.
“I provide red stones to my pigeons to keep them healthy and avoid problems like constipation.”
By picking it up with their beaks, you can see many birds eating small gravel on the stony roads and backyards.
“My pet birds eat stones regularly to replace the excreted ones as they need them to break the hard food particles like seeds.”
They can eat everything that comes before them without any discrimination to fill up their stomach. So, you cannot consider them only omnivorous, as they can eat leafy vegetables and fruits also.
“I was amazed to see my birds eating worms, seeds, berries, food leftovers, and even gravel with their fleshy beak and never so no to any food type.”