Some whale watching experiences are full of excitement, particularly when these massive marine mammals breach and slap the water with their fins. <\/p>\n
But the quieter moments are no less thrilling \u2013 as researchers found out during an expedition to Dominica in 2022 when they came across a family of sperm whales<\/a> taking a nap.\u00a0<\/p>\n \u201cThese whales spend approximately 7 percent of their day sleeping vertically near the surface in short 10\u201315-minute periods,\u201d says\u00a0Kat Millage<\/a>, a marine scientist at National Geographic Pristine Seas.\u00a0<\/p>\n Nat Geo Pristine Seas shared the magical footage of the huge whales slumbering while upright, like towering underwater trees, on\u00a0Instagram<\/a>.\u00a0<\/p>\n The National Geographic Pristine Seas team came across the sleeping sperm whales during an expedition in Dominica, an island nation in the Caribbean Sea. Credit: National Geographic Pristine Seas<\/p>\n \u201cThis behaviour allows them to stay alert to predators and easily breathe when they wake up (whales breathe air!),\u201d adds Millage.\u00a0<\/p>\n But this can put these ocean giants in harm\u2019s way. \u201cBecause sperm whales sleep so close to the surface, they are vulnerable to being hit by boat propellers,\u201d says Millage. \u201cA key conservation challenge is minimising potential interactions between ocean-going vessels and\u00a0sperm whales<\/a>.\u201d<\/p>\n Dominica\u2019s 200-or-so resident sperm whales recently received new protections thanks to the 2025 establishment of the\u00a0world\u2019s first sperm whale reserve,\u00a0<\/a>which aims to regulate marine activities and protect their habitat.\u00a0<\/p>\n A researcher drifts slowly beside the family of sleeping sperm whales. Credit: National Geographic Pristine Seas<\/p>\n Image and video credit: National Geographic Pristine Seas<\/p>\n More amazing wildlife stories from around the world<\/p>\n