Raging Bull: Why Bulls are so Aggressive and Angry

We’ve all seen the signs. BEWARE OF BULL. Instinctively, we know not to enter a field with a bull in it. It’s common knowledge that bulls are aggressive and dangerous, right? But do bulls really deserve the labels we assign them?

The truth is, bulls really are more aggressive than regular cows, and it’s wise to stay away from them. Bulls tend to be more territorial, have higher hormone levels, and are usually less socialized with humans than cows, and they are much larger and stronger to boot.

Why Bulls are so Aggressive and Angry

In this article, we’ll explore exactly what makes bulls so aggressive and angry, and find out if it’s nature or nurture that makes them this way. We’ll also discover the mystery behind why a waving red flag boils bulls’ blood.

Why are Bulls so Aggressive?

Bulls tend to be more aggressive than cows, and due to their weight they are also more dangerous. Bulls’ aggression stems from three main causes, which are that bulls are more territorial than cows, bulls have higher levels of testosterone than cows, and bulls are less socialized than cows.

Let’s look at each of these in detail and see how they cause aggression in bulls:

1. Bulls are Territorial

Usually, cow society is quite egalitarian, with common feeding and maternal care, however bulls can be very territorial, especially when there are females around.

Bulls have been known to attack walkers and hikers who wander in to their territory, and bull attacks can be extremely dangerous.

In an article in Hoard’s Dairyman, it was explained that bulls have a fight-or-flight radius of around 20 feet. Inside this radius, bulls can not expect to outrun a predator and is much more likely to attack.

2. Bulls Lack Socialization

Bulls usually live by themselves, separate from the rest of their herd. Because of this, bulls do not socialize as much with other cows, which results in them being more aggressive.

In addition to being less used to being around other cattle, bulls are handled a lot less frequently on the farm than other cows.

Apart from the occasional hoof trimming and some handling around breeding season, bulls are often left to their own devices for several months at a time.

This makes bulls more aggressive around humans, since they don’t have the opportunity to become used to working around people regularly.

Related Article: What do Bulls Eat?

3. Bulls Have High Levels of Testosterone Hormones

Bulls are primarily used for breeding, which means their reproductive organs are always left intact. 

Compared to regular beef cattle, which are usually castrated, bulls have a much higher level of the hormone testosterone in their system.

Levels of testosterone are directly correlated with levels of aggression, meaning bulls are more aggressive than steers, cows, and heifers.

This high level of testosterone is one of the reasons why we don’t eat bull meat, since testosterone gives the meat a bad taste.

If a bull is near a heifer in heat, his biological urges kick in and he will trample whoever or whatever gets in his way, even running through or jumping over fences.

Read More: How Many Calves can a Single Cow Have?

Why Do Bulls Hate Red Flags?

Wouldn’t you get annoyed if an annoying matador was following you around, taunting you by waving a flag in your face?

Bulls are red-green colorblind, which means they can not tell the difference between red and green colors. It’s not the red color of the waving flag that infuriates bulls, but the matador taunting and goading the bull.

Read More: Can Cows and Bulls See In Color?

Are All Bulls Aggressive?

All bulls are naturally aggressive, and even bulls who are more socialized with humans are still more aggressive than steers or cows.

In some circumstances, bulls may become socialized with the farmer who feeds them, especially when calves have been raised since birth by the same farmer.

Even when a bull is socialized, due to their higher hormone levels they are naturally more aggressive and are more likely to attack.

In a 2008 study in the Journal of Agromedicine it was found that special housing and confinement facilities are effective in preventing fatalities caused by bull attacks.

Farmers understand this, which is why they usually keep bulls separate from the rest of the herd in a bull-pen or an isolated field.

Read more: Where do Bulls Live? 


To sum up, bulls do generally live up to the aggressive and angry stereotypes we label them with, due to their higher testosterone levels, lack of socialization, and territorial nature.

All bulls are naturally aggressive, especially compared to regular cows. Even some bulls which are socialized with humans can still act aggressive in certain situations, most notably during breeding season when there are heifers in heat nearby.

To get to a cow, bulls will trample anything that gets in their way, including fences and walls. Since bulls can weigh up to two tons, it’s extremely dangerous to be around them.

Finally, the common myth that bulls are enraged by the color red is simply not possible. Bulls are color blind, and it’s the shaking motion of the flag that winds them up, not the color!

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