This is often the case in nature - two brown bears fighting, one of them an adult male and one an adult female. The cause is that the male bear wants to attack the female's two cubs, and to protect her children, the female bear fights to the death.

Why would a male bear risk killing a brown bear cub? Let's learn more about brown bears.

Although brown bears belong to the order Carnivora, they are omnivorous and have a much higher proportion of plant food, reaching 75% on average.

This is because the brown bear's bulky size and relatively short limbs limit its flexibility, so in terms of hunting prey, the European brown bear is inferior to other carnivores.

Although brown bear cubs are cared for by adult females, their mortality rate in their first year is still very high, and the biggest factor in cub mortality investigations, apart from malnutrition, is the killing of other animals, with the largest proportion of similar males.

Why do male brown bears kill their cubs? First, the male bears kill cubs that are not their offspring, but the offspring of other male bears, and they kill similar cubs for two reasons.

The first is hunger. Although brown bears are explosive in combat, their hunting ability is not complimentary, especially for large herbivores, the hunting success rate is so low that it is miserable, so the main sources of meat for brown bears are rodents, fish, insects, and carrion.

However, these meats are not readily available, especially in autumn and spring, when brown bears prepare for hibernation and wake up from hibernation in spring and need to replenish their strength as soon as possible when some adult males will target similar cubs.

This is not only true of brown bears, but also of polar bears, which have been found to have attacked similar cubs on several occasions.

Second: Stimulating female brown bears to come back into heat. Once a female brown bear has given birth, she will not go into heat for at least 1.5 years, or at least two years if you count the gestation period, but not the males, who are in a fixed heat from May to July each year. What can be done about this?

Male brown bears will actively hunt female cubs to get them into heat again, and scientists have found that this works so well that when the cubs die, the female will go into heat again within the next 1 week-1 month so that the male can reproduce normally.

In fact, in nature, many male animals kill their cubs, the main purpose of which is to stimulate the female to go into heat again, for example, when the lion king changes, the first thing the new lion king does after taking office is to kill the cubs in the pride. Although it may seem cruel, it is a common occurrence for wild animals.