Pupping season peaks between April and July. The average life-span of harbor seals is 30 years, although few harbor seals live longer than 25 years. Predators of harbor seals include sharks and killer whales, eagles and coyotes depending on the region, and humans. Gray seal pups are born with a silky, creamy white lanugo coat and undergo their first molt at 2 to 4 weeks of age. Gray seal pups are about 2.5 to 3.5 feet long and weigh 24-44 pounds.
Gray seals are gregarious and polygynous.
Gray seal pups are nursed for about 3 weeks. Predators of gray seals include sharks, possibly killer whales, and humans. This name refers to the inflatable septum, or hood, which male hooded seals possess and use for courtship displays and aggressive encounters. At about 14 months, they acquire a mottled pelage. Pups are approximately 3 to 3.5 feet in length and may weigh 33-66 pounds.