Are Squirrels Immune to Snake Venom?

Several types of squirrels are immune to snake venom; some are highly resistant, and some show weak resistance to this venom. Natural evolution helped to develop this characteristic for better survival in the environment. 

Are Squirrels Immune to Snake Venom? Some kinds of squirrels, like ground and grey squirrels, are immune to snake venom due to a special anti-venomous blood present in their body and the natural evolution process. They protect them from snake attacks by mobbing and making their tails hot. They can even kill the snakes to protect their babies and to cover themselves in their dead skin. 

A special kind of protein present in their blood interacts with the protein in venom and produces resistance in them.

How are squirrels immune to snake venom?

They have unique qualities that make them immune to the venomous snake bite.

Snake venom is actually toxic saliva that contains harmful chemicals mainly based on protein to destroy the body cells. However, some factors make them able to tolerate this venom and help them survive. 

Anti-venomous proteins

Some squirrels have a special kind of protein in their blood that helps them survive the bite of venomous snakes. These are actually venom interactive-proteins whose primary goal is to fight against it. 

These proteins interact with the proteins present in this venom, and a reaction occurs. There are two different mechanisms of their binding to each other to create different immunity levels. 

One venom protein interacts with many venom interactive proteins in some species, or many others interact with venom proteins in other species. Resistance is highly dependent on the age and size of the snake and poison production in a bite.

A squirrel does not get the strong intensity of poison if a small size baby snake bites it because it has not developed enough poison.

On the other hand, a large one has a lot of poison in its bite, which becomes hazardous for an animal. Sometimes small snakes produce less venom which becomes a reason for its reduced intensity and does not affect them.

Evolutionary process

Both are living in California for thousands of years, and they have adapted to specific qualities.

Ground squirrels are immune to this venom. It is nature’s rule to select only those individuals in a species that have better qualities among the whole specie.

The evolutionary process is essential for animals because every animal struggles to survive in the environment.

This venom was present in a single ancestor thousand years ago, which evolved into many lineages of snakes. 

You can see a lot of their venomous types in the environment, which are the products of this natural evolutionary process. The same is true because many groups of squirrels did not contain anti-venomous proteins long ago. 

But they got this anti-venomous blood quality from their ancestors.

What type of squirrels is immune to snake venom?

Their ability to resist snake venom increase with an increased encounter with this toxic saliva. On the other hand, it also decreases when there is no snake around to bite them. 

Some have stronger, and some have weaker resistance against the venomous bite according to the type of their specie. 

Grey squirrels

They are primarily present in eastern America and are around 25 cm in size. They have strong resistance against a specific kind of snake called timber rattlesnake. 

They can distinguish between their venomous and non-venomous types, which makes it easy for them to defend themselves.

So they prefer to attack their non-venomous type to ensure a high survival rate. They also show a weak immunity against the bite of pacific rattlesnakes. 

Ground squirrels

These are heavy and one of the longest ones, which are more than one foot in size. They are native to southwestern areas of the united state and are also called rock squirrels.

They adapt this resistance over time through the process of natural selection.

It is a step in evolution that allows more suitable species having significant features to survive in the environment. 

Such species pass the genes of these qualities to their offspring to develop this immunity.

These offspring can even become significantly changed from their ancestors due to evolution. Therefore, they do not have strong resistance to this venom.  

Do squirrels attack snakes?

Squirrels belong to the omnivores group of rodents and can eat everything they get. 

They attack the snakes for a different purpose by throwing pebbles and small stones. Finally, they furiously bite the tail of the snakes, which becomes the cause of a severe infection.

To protect their babies

Baby squirrels do not have much immunity to tolerate the venom, so they are their easy targets. 

Mother squirrels attack them even before they attack their babies to protect them.

It hides the babies in the furrow to keep them safe in case of a snake encounter. It initially hits the snake’s tail and jumps towards its head for protection. 

To use the skin of the snake

Some of their kinds attack them to use their skin for different purposes.

For example, ground squirrels love to wear their dead skin to hide from others. So they chew the skin of rattlesnakes to make it softer so they can use it comfortably.

They wear this chewed skin just like a coat and look like a snake from far away.

The smell of this skin makes others confused, and they think of them as original ones. It makes them less vulnerable to attack and other predators. 

To eat them

They can eat everything, whether meat or vegetables, as they are omnivores animals. They kill snakes to eat them whenever they find an opportunity to attack them. 

But they do not prefer to intentionally search them when they have enough reserve for other food sources. Normal-size squirrels mostly attack those which are smaller in size because it is convenient for them to fight with them. 

How do squirrels protect themselves from snake attacks?

Squirrels are intelligent rodents that can prevent themselves from snake attacks in many ways. In addition, they show quick reflexes to protect themselves according to the dangerous situation. 

Hot tails

A hot tail mechanism is the unique self-defense mechanism in ground squirrels that they use against an attack.

They lift their tail, move it back and forth and rub their fur to wave it. This waving increases the blood flow in their tail called the hot tail. 

They use this quality to warn the snakes not to make a mistake in attacking them.

Sometimes they push the warmer blood from the upper part of the body to the tail portion to alert the predator. It is a sign for them to be prepared for the attack of squirrels if they try to encounter them.

Moreover, they have highly sensitive hair, which helps them to sense anything unusual in the environment.

These hair are called vibrissae, primarily present on their face and send messages to their brain. These hair change their direction to the danger, which helps them to move to find the snake. 


They have another essential phenomenon to protect themselves from snake venom, and that is mobbing. It is actually a behavior in which many individuals gather who are at risk of a predator’s attack.

It occurs through a proper call system in which a squirrel makes a specific voice to call its other mates. This call aims to warn others about the predator’s attack and to run away. 

Their babies also give whistling calls when a snake approaches and try to kill them. Their adults hear this call and reach out to rescue them in the best possible way. 

Some of them can differentiate between venomous and nonvenomous animals and act according to the situation.

However, they mostly approach attacking non-venomous ones because it makes them less vulnerable to hazards.

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