Pod of sperm whale relaxing after a short sleep (Physeter macrocephalus) Researchers first saw this unusual sleep behavior in sperm whales in 2008. The scientists in that study found that sperm whales dozed in this upright drifting posture for about 10 to 15 minutes at a time, Vulnerable (IUCN). The sperm whale is the largest of the toothed whales. Sperm whales are known to dive as deep as 1,000 meters in search of squid to eat. Dominica, Caribbean Sea, Atlantic Ocean. Photo taken under permit n°RP 16-02/32 FIS-5.

physeter macrocephalus physeter catodon physeter physeteridae cetacea mammalia vertebrata physeter macrocephalus physeter catodon adult group sleep high angle view overview underwater shot blue dominica island tropical sea physeter sperm whale (physeter catodon) sleepy caribbean sea vulnerable (iucn) vu cites appendix 1 january february saltwater species nobody adults groups sleeps dormant sleeping high angle shot overhead shots overhead shot overhead sight overhead sights overhead view overhead views overviews global sight global sights full length subaquatic photos subaquatic sights seen under the water photos under the water underwater shots subaquatic image underwater view submarine images submarine sights submarine sight submarine photos submarine photo underwater views submarine photographies submarine photography underwater underwaterphoto underwaterpicture underwaterphotography underwaterphotographies underwaterphotos underwaterpictures commonwealth of dominica tropical seas tropical oceans tropical ocean macrocephalic sperm whale sperm whales (physeter catodon) macrocephalic sperm whales sleepiness put to sleep putting to sleep fall asleep falling asleep carribbean sea vulnerable species salt water species marine species with nobody stage of development individual enumeration rest shot colour lesser antilles (archipelago) antilles islands archipelago america sea marine area area physeteridae cetacea mammalia vertebrata sperm whale whale cetacean marine mammal mammal wild animal north atlantic ocean atlantic ocean world sea and ocean threatened endangered species iucn red list of threatened species species convention on international trade in endangered species of wild aquatic species species particularity