Seals can hold their breath underwater for varying durations depending on the species. Generally, seals can hold their breath for about 15 to 30 minutes, but some species, like elephant seals, are exceptional divers and can hold their breath for up to two hours. Elephant seals are the champions in breath- holding, often staying submerged for well over an hour while diving to great depths to hunt

. This remarkable ability is supported by physiological adaptations such as large lung capacity relative to their body size, a thick layer of blubber for insulation, and a specialized "dive response" that conserves oxygen by slowing heart rate and redistributing blood flow to vital organs. Unlike humans, seals can trigger this dive response before submerging, maximizing oxygen efficiency

. Moreover, seals have evolved a unique mechanism to sense their blood oxygen levels directly, rather than relying primarily on carbon dioxide buildup to signal when to breathe. This allows them to regulate their dive times more effectively and avoid blackouts due to oxygen deprivation

. In summary:

• Typical seals hold their breath for 15–30 minutes.
• Elephant seals can hold their breath for up to 2 hours.
• Adaptations include large lungs, dive response, oxygen sensing, and oxygen conservation mechanisms