Elephant Seals Take Power Naps During Deep Ocean Dives - The New

Elephant seals enter 'sleep spiral' during deep ocean dives - KVIA

Elephant Seals Wandering through Time and Place

Northern elephant seals can get less sleep than almost any other animal : NPR

Northern elephant seals sleep just two hours a day at sea

Elephant Seals - Point Reyes National Seashore (U.S. National Park Service)

Elephant Seals Take Power Naps During Deep Ocean Dives - The New York Times

Sleeping elephant seals fall through ocean's depths, and some even nap on the sea floor - ABC News

Deep-diving seals reveal secrets of carbon monoxide

Mapping uncharted undersea volcanoes, and elephant seals dive deep to sleep, Science

Sleepy Seals Bug Woman – Adventures in London

Elephant seals dive asleep – and urchin death riddle solved

Meet Nature's Extreme Athlete, Elephant Seals - Bay Nature Magazine

Elephant seals nap while they dive, study finds, shedding new light on sleep

Elephant Seals - Point Reyes National Seashore (U.S. National Park Service)