SPERM WHALE
Reaching lengths of up to 66 feet (20 m), sperm whales are the world’s largest toothed predators. They sustain their huge size by diving to incredible depths in search of their preferred prey, squid. Scientists have recorded sperm whales at depths of up 7,380 feet (2,250 meters). They can remain submerged for as long as 90 minutes and have also evolved to survive under extreme pressure. One of their most important physiological features is a flexible ribcage that allows for lung collapse and the reduced absorption of nitrogen. Like elephant seals, their blood carries extra myoglobin and red blood cells, and they are able to direct their bloodstream away from non-essential organs while diving in order to make the most of depleted oxygen levels. In the pitch black of the abyss, sperm whales find their prey through echolocation.
CUVIER’S BEAKED WHALE
In 2014, scientists named Cuvier’s beaked whales the deepest diving animals of all when they tracked one on a dive to 9,874 feet (2,992 m). The dive lasted for 2 hours and 17 minutes, making this whale the longest-diving mammal on record as well as the deepest. Cuvier’s beaked whales dine a diet of squid and deep-dwelling fish and, like the sperm whale, have fully flexible ribcages