Octopuses, stranger than you think.
Blue blood, arms that taste, a mother who guarded her eggs for four and a half years and an escape down a drain pipe. Every fact traced to a source and dated where it can change, plus games, printables and an eraser called Useless who is trying very hard not to be eaten.
The short version
Octopuses are molluscs: boneless invertebrates related to clams. Monterey Bay Aquarium: Giant Pacific octopus Cephalopod, the group octopuses belong to, means ‘head foot’ in Greek, because the head connects straight to the arms. Smithsonian Ocean: Octopuses, squids and relatives
Octopuses have eight arms. Squid and cuttlefish have eight arms plus two longer tentacles for snatching prey. Smithsonian Ocean: Octopuses, squids and relatives Most octopuses spend most of their time on the ocean floor, and most live alone in a den. Smithsonian Ocean: Octopuses, squids and relatives
They don’t last long. Octopuses usually live no more than a year. The giant Pacific octopus is a long-lived exception, at about three to five years. Monterey Bay Aquarium: Giant Pacific octopus
And they are clever in ways that are hard to measure. Octopuses can untie knots, open jars and get into toddler-proof cases, and they are expert escape artists. Smithsonian Ocean: Octopuses, squids and relatives There’s a whole page on octopus smarts and escapes.
- There are roughly 300 species of octopus, and the number keeps changing as new species are discovered. Smithsonian Ocean: Octopuses, squids and relatives · checked 28 Oct 2026
Nobody knows exactly. New species keep turning up, especially in the deep sea, and some have no scientific name yet. Every disagreement we found →
Start somewhere
Three hearts & blue bloodCopper blood, arms that taste, a doughnut-shaped brain and a beak.
Smarts & escapesJar-opening, coconut-carrying, and Inky’s trip down the drain.
Twelve octopusesFrom the giant Pacific to the dumbo, the mimic and the argonaut.
Eggs & mothersBreed once, guard the eggs, and the 53-month record.
Where they liveRock pools, coral reefs, the open ocean and nearly 7 km down.
Octopuses and us330-million-year-old relatives, the Kraken and that plural.
Tile photos are credited on their pages and on the credits page.
The mother who waited
A deep-sea octopus, Graneledone boreopacifica, brooded her eggs for 53 months (May 2007 to September 2011) at 1,397 m in Monterey Canyon: the longest egg-brooding period known for any animal. Robison et al. 2014, PLOS ONE (peer-reviewed) · checked 28 Oct 2026 In all that time the researchers never saw her leave her eggs or eat anything, not even small crabs and shrimp that wandered past. MBARI: Deep-sea octopus broods eggs for over four years
And the one that went down the drain
In 2016 an octopus called Inky escaped from the National Aquarium of New Zealand in Napier. His tank lid had been left slightly open; he slid across the floor and down a 15 cm drain pipe that led to the sea. BBC News: Octopus makes great escape from New Zealand aquarium Read more on smarts & escapes.
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Octopus printables
Fact-checked PDFs in A4 and US Letter.
Octopus Species Fact Cards
Twelve octopus fact cards, from the giant Pacific octopus to the dumbo and the argonaut, with dated records, an Octopus or Not? sorting game and a tracker
Octopus Maths Worksheets
Real octopus numbers for ages 8 to 12: hearts, arms, suckers, depths and brooding months, with every answer worked out
Octopus Body & Life Cycle Pack
Label the octopus, three hearts and blue blood, egg-to-adult sequencing cards and the 53-month mum, with answer keys
Octopus Activity & Colouring Pack
Colouring pages, a maze, word search and spot-the-difference puzzles for ages 4 to 9
Octopus Facts Poster Set
Six fact-checked posters, from three hearts and blue blood to the escape artist who went down the drain
Octopus Quiz & Word Puzzles Pack
A crossword, code breaker, fill-the-gap facts, number match, myth busters and a 16-question quiz, with answer keys
Best valueThe Complete Octopus Printables Bundle
All six packs plus a guide, A4 and US Letter, in one download.