Animals that must migrate across the ocean have to rely on very limited sleep to avoid predation. For example, northern elephant seals sleep about 20 minutes at a time throughout the day, resulting in about 2 hours total per day.
While at sea, northern elephant seals must worry about catching their prey, while also avoiding being caught themselves by their predators such as sharks and killer whales. They dive to the bottom of the sea to avoid predators, only coming up to the surface for a few minutes.
To find out if northern elephant seals sleep at the bottom of the ocean, a group of researchers, “recorded the animals’ brain waves, revealing when they were asleep. Motion sensors were also strapped onto the seals” (ScienceNewsExplores). They discovered that northern elephant seals dive about 60 to 100 meters from the surface when they want to sleep. They then starts to glide, which will lead them to fall asleep, with their body standing up for some minutes.
They then go into a rest stage called a REM sleep where their body becomes immobilized. They will then flip to their bellies and drift down to the ocean floor. However, the northern elephant seals don’t live like this throughout the whole year. When they are back on land, they will sleep for 12 hours a day.
Seals dive so far deep in the ocean to escape their predators, who lurk near the ocean’s surface.
While at sea, northern elephant seals must worry about catching their prey, while also avoiding being caught themselves by their predators such as sharks and killer whales. They dive to the bottom of the sea to avoid predators, only coming up to the surface for a few minutes.
To find out if northern elephant seals sleep at the bottom of the ocean, a group of researchers, “recorded the animals’ brain waves, revealing when they were asleep. Motion sensors were also strapped onto the seals” (ScienceNewsExplores). They discovered that northern elephant seals dive about 60 to 100 meters from the surface when they want to sleep. They then starts to glide, which will lead them to fall asleep, with their body standing up for some minutes.
They then go into a rest stage called a REM sleep where their body becomes immobilized. They will then flip to their bellies and drift down to the ocean floor. However, the northern elephant seals don’t live like this throughout the whole year. When they are back on land, they will sleep for 12 hours a day.
Seals dive so far deep in the ocean to escape their predators, who lurk near the ocean’s surface.