Whales are air-breathing mammals with exceptional breath-holding capacity. The ability to stay submerged varies drastically; many baleen whales dive for only 10 to 20 minutes, while specialized divers can remain underwater for hours. These physiological differences reflect their varied foraging strategies and evolutionary specializations.
The Deep Dive Record Holders
The species that holds the record for the longest and deepest documented dive is the elusive Cuvier’s beaked whale (Ziphius cavirostris). Tagged individuals have been recorded staying submerged for an astonishing 222 minutes—three hours and forty-two minutes. These extreme dives are well beyond their typical routine, however, as the median duration for their deep foraging dives is around 60 minutes.
The sperm whale (Physeter macrocephalus) was historically thought to be the most capable diver. While they no longer hold the absolute record, their typical dives routinely last 35 to 45 minutes. The maximum documented duration is around 90 minutes. Both sperm whales and Cuvier’s beaked whales are deep-sea hunters, relying on exceptional breath-holding to pursue prey like squid in the abyssal zone.
Biological Mechanisms for Oxygen Management
The ability of deep-diving whales to remain submerged for extended periods is due to physiological adaptations known as the mammalian diving response. Oxygen storage is maximized in both the blood and the muscles. Whales possess a much higher concentration of hemoglobin in their blood and myoglobin in their muscle tissue compared to terrestrial mammals, creating a large internal oxygen reservoir.
When a whale begins its descent, it initiates a cardiovascular shift to manage its limited oxygen supply. The heart rate slows significantly, a process called bradycardia, which conserves energy and oxygen. Simultaneously, peripheral vasoconstriction occurs, restricting blood flow to non-essential organs like the kidneys, liver, and skeletal muscles. This shunts oxygenated blood to the most sensitive organs, the brain and the heart, ensuring they remain functional throughout the dive.
To cope with the immense pressure at depth, which can exceed 200 atmospheres, the whale’s flexible ribcage allows its lungs to collapse. This action forces nitrogen gas out of the air sacs and into the bronchial tubes, which are less permeable to gas transfer. This prevents nitrogen from dissolving into the bloodstream and tissues under high pressure, thereby avoiding decompression sickness, commonly known as “the bends.”
What Triggers the End of a Dive
The primary constraint on a whale’s dive duration is not simply running out of oxygen, but reaching its “aerobic dive limit” (ADL). The ADL is the point where the whale’s metabolism switches from using stored oxygen (aerobic) to generating energy without oxygen (anaerobic). For the majority of a dive, the whale operates aerobically, conserving muscle oxygen stores. Once the ADL is exceeded, the restricted skeletal muscles rely on anaerobic metabolism, which produces lactic acid as a waste product.
The buildup of lactic acid and the increasing concentration of carbon dioxide in the blood are the physiological signals that prompt the whale to surface. Marine mammals possess a higher tolerance for carbon dioxide than humans, allowing them to suppress the urge to breathe longer. When the whale surfaces, it must recover from the anaerobic portion of its dive by metabolizing the accumulated lactic acid.
This recovery period, though often brief, is when the whale rapidly replenishes its oxygen stores in preparation for the next descent. The duration of this recovery time is directly linked to how far the whale pushed beyond its routine aerobic limits.