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When are most bear cubs born?
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bear
Grizzly bear in Jasper National Park, western Alberta, Canada.
Most bear cubs are born in January or February.1
This timing is a result of delayed implantation, a reproductive process where the fertilized egg remains dormant in the uterus. This ensures that the cubs are born while the female is in her winter den, allowing them to emerge in the spring when food sources are more abundant. During this period of winter lethargy, the cubs are maintained by maternal warmth and suckle until they are ready to leave the den.12