Do polar bears prey on penguins?

Polar bears rarely meet with one another, only to breed will two adults see each other face-to-face. The fathers leave the mothers right after the mating season, or even during the mating season, then live on their own to hunt for food. The females are a different case. Every 5 years or so, the female gives birth, so the female spends all of that time hunting, and when they are pregnant they dig a den in a soutable spot.