Northern Elephant Seals Sleep in Deep-Sea Spirals to Avoid Predators

Northern Elephant Seals Sleep in Deep-Sea Spirals to Avoid Predators

Northern elephant seals have been found sleeping while drifting hundreds of meters below the sea surface to avoid predators. The mammals, known for reaching depths of up to 2,500ft (760m), sleep for only two hours per day in what researchers describe as "nap-like sleeping dives." A team of scientists followed eight wild northern elephant seals on their foraging trips lasting approximately seven months and spanning over 6,200 miles.

The study involved recording the animals' brain activity, heart rate, movement, and body position during these underwater naps. According to the research findings, the seals would fall asleep and descend in "sleep spirals" for about 20 minutes at a time before resurfacing.

Lead researcher Dr. Mariana Torres explains: "Our observations provide unique insights into how these deep-diving marine mammals balance their need for rest with predator avoidance behaviors." She adds that this is especially important considering that northern elephant seals are often targeted by large shark species such as great whites.

Notably, the scientists suggest that sleeping areas may be just as crucial as active hunting areas for these animals. This is because resting helps them conserve energy during long-distance migrations when food resources might be limited or unpredictable.

Dr. Benjamin Saunders from the Marine Mammal Institute elaborates: "These findings highlight how important it is to consider both feeding and resting habitat when studying animal movement patterns and planning conservation strategies."

As a result of this groundbreaking research on northern elephant seal behavior during migration periods could potentially inform future conservation efforts aiming at protecting critical habitats not only used for feeding but also essential resting areas where they can safely nap away from lurking predators.