Several factors can contribute to cannibalism in grizzly bears:
1. Food Scarcity: When food resources are scarce, particularly during the spring and early summer when natural prey is limited, female grizzly bears may resort to cub predation to ensure their own survival.
2. Infanticide: Male grizzly bears may kill the cubs of other males to eliminate potential competitors and increase their chances of mating with the female. This is a survival strategy aimed at increasing reproductive success.
3. Sibling Competition: In times of food shortage, female grizzly bears may kill weaker cubs to redirect resources to stronger ones, ensuring the survival of the fittest offspring.
4. Lack of Experience: First-time mothers or younger bears may inadvertently harm or kill their cubs due to inexperience in caring for them. This can occur during the vulnerable newborn period when cubs are entirely dependent on their mothers for survival.
5. Environmental Stress: Environmental stressors, such as habitat loss, fragmentation, and human-bear conflicts, can contribute to increased levels of stress and anxiety in bears, leading to abnormal behaviors, including cub predation.
It's important to note that cub predation in grizzly bears is not the norm and occurs under specific circumstances when resources are scarce or environmental conditions are challenging. In most cases, grizzly bears display maternal care and fiercely protect their offspring from potential predators.