Polar Bear — Cannibalism Due to Climate Change
These animals are more likely to eat their young in the spring and summer, as the seal populations — and ice floes on which to hunt for them — begin to become less accessible.
Cannibalism usually takes the form of larger and more aggressive male bears targeting smaller females and vulnerable cubs. That’s not always the case, as a mother polar bear in the Nuremberg Zoo ate her starving cubs after an attempt by zookeepers to minimize human contact with them in their formative years.
Sand Tiger Shark — Cannibalism Before Birth
Competition among siblings is common in the animal kingdom, but few animals start as early or as viciously as the Sand Tiger Shark. That’s because the mothers eat their young while they’re still in utero. Or more accurately, the fetuses of potential offspring vie for survival.
Females of the species will typically get pregnant by a number of different males at a time, and they carry many eggs but only have two uteri. That creates a situation where multiple offspring will devour one another until they’re reduced to only two.
Chicken — Cannibalism for Calcium
Chickens aren’t recognized as the smartest birds on the planet, so it’s only natural that their acts of infanticide and cannibalism are not always intentional.
In many cases, eggs from domesticated chickens simply break due to a coop being overcrowding, and then a chicken accidentally eats it not realizing what it is. Unfortunately, this can lead to the chicken developing a taste for eggs and even sharing that with others.
Prairie Dog — Cannibalism of Nieces and Nephews
Not all prairie dogs kill their young, but it’s been observed with some frequency in three different species: Gunnison’s, Utah, and black-tailed. But the issue is most prolific in black-tailed prairie dog communities, where up to a third of offspring can fall victim to infanticide.
Normally it’s not the mother, father, or even a competing male that kills the young. Instead, female family members of the mother will kill and eat her litter when she leaves for an extended bout of foraging.
Lion — Cannibalism for Social Dominance
While male lions maintain harems of females that they breed with, these big cats are renowned for being good mothers and fathers — and female lions are often even willing to nurse the cubs of other females in the pride. Unfortunately, infanticide is not uncommon thanks to the scarcity of available breeding partners.
Fathers evict their cubs from the pack at a certain age so they don’t become competition, and these roving young lions will often seek out an established pride to claim as their own. In many instances, lions who take a new pride will kill the cubs both to remove competition and bring the females back into heat.