# Common octopus (*Octopus vulgaris*)

Octopuses are clever sea creatures with eight arms covered in suction cups. They can change color and texture to hide from predators or sneak up on prey in the ocean.

- **Category:** [Invertebrate](https://www.snappit.app/explore/categories/invertebrate)
- **Rarity:** Common
- **Danger:** 2/5 · Low
- **Habitat:** Marine
- **Also known as:** Common Octopus, European Octopus

![Octopus](https://res.cloudinary.com/drieglelr/image/upload/v1771426044/objects/6275.jpg)

## Appearance

The Octopus has a soft, bulbous head and eight powerful arms lined with suckers. Its skin can rapidly change color and texture, often blending seamlessly with rocky or coral surroundings.

## Taxonomy

- **Kingdom:** Animalia
- **Phylum:** Mollusca
- **Class:** Cephalopoda
- **Order:** Octopoda
- **Family:** Octopodidae
- **Genus:** Octopus

## Common octopus, up close

The common octopus (Octopus vulgaris) is a soft-bodied mollusc with eight arms that lives on rocky, sandy and muddy seabeds of the Mediterranean Sea and the eastern Atlantic, from southern England to West Africa. It spends the day in a den, hunts crabs and shellfish mostly at night, and can change the colour and texture of its skin in moments. Look-alike octopuses in the Americas, Australia and other regions were long given the same name, but scientists now treat several of them as separate species.

Also called: Pulpo (Spanish), Polpo (Italian), Polvo (Portuguese), Pieuvre (French), Gemeiner Krake (German), Chtapodi (Greek).

Three hearts, blue blood, about 2,000 suckers and skin that changes in moments. Spin it, tap it, then test yourself.

### Special abilities

- **Skin Shift** (3 kinds of colour organs): The common octopus changes the colour, pattern and bumpiness of its skin in moments, to blend in or to signal. [4][10]
  - Chromatophores open and close under direct nerve control, not hormones, so patterns can flicker across the skin.
  - Beneath them, iridophores add shine and leucophores reflect white light.
  - Skin bumps called papillae rise to copy rough rock or weed.
  - In life, its colours range from yellow-brown and red-brown to dark brown or grey.
- **Ink Decoy** (3 shapes of ink): When attacked, it squirts dark ink out of its siphon and slips away while the predator is confused. [9][4]
  - Ink is made in the ink sac, darkened by melanin and mixed with mucus from the funnel organ.
  - Thin ink makes a smoke screen. Thicker, mucus-rich blobs called pseudomorphs look roughly like a cephalopod, like a decoy.
  - Long, thin strings of ink are called ropes.
- **Jet Escape** (2.5× blood pressure when busy): To make a quick getaway, it fills its mantle with water and squirts it out through the siphon, shooting backwards. [4][6][11]
  - Octopuses crawl on their arms, and they can jet when they need a fast escape.
  - Jetting is hard work: pressure in the main artery rises from about 40 cm of water at rest to 100 cm or more during exercise.
  - The main heart hardly speeds up. Instead, it pumps more blood with each beat.
- **Gap Squeeze** (0 bones): With no skeleton, an octopus can pour its soft body into a crack and vanish into its den. [4][13]
  - Its old mollusc shell is reduced to two tiny rods (stylets), so the beak is the main hard part that has to fit through.
  - Common octopuses choose dens in rock cracks or make them in sand and mud, and change them, for example with stones and shells.
  - Staying in a den keeps them safer from predators such as groupers, wrasses, eels and sharks.
- **Taste by Touch** (220–320 suckers per arm): An octopus explores cracks with its arm tips and tastes what it touches, so it can find a hidden crab without seeing it. [14][4][8][5][6]
  - Young common octopuses hunt mainly by feeling and tasting in crevices and under rocks, and they prefer crabs.
  - Adults also wrap a rock in their arms and web, then use the arm tips to find and flush out prey.
  - In the California two-spot octopus, sucker cells carry chemotactile receptors that detect chemicals on surfaces, such as on prey.
  - About 300 million of its 500 million nerve cells are in the arms, which helps each arm work partly on its own.
  - Where the nerve cells are: Arms ≈300 million; Optic lobes ≈130 million; Rest of the brain ≈40 million
- **Inside View** (3 hearts): Peek inside: three hearts, blue blood, a ring-shaped brain, a hard beak and an ink sac. [4]
  - One main heart pumps blood round the body, and two gill hearts push it through the gills.
  - The blood is blue because of haemocyanin, a copper-based pigment that carries oxygen.
  - The brain wraps around the gullet like a ring.
  - The ink sac is tucked against the digestive gland. Its duct joins the gut, and the ink leaves through the siphon.
- **Egg Guardian** (up to 500,000 eggs in one brood): A mother octopus hangs strings of eggs from the roof of her den and looks after them until they hatch. [4][15]
  - She lays 100,000 to 500,000 eggs, each about 2 mm long, in strings called festoons.
  - She blows fresh water over them and strokes them to keep algae and germs off, for up to 4–5 months in cool water.
  - She usually does not eat during this time and can lose a third or more of her weight. It is her only brood: she reaches the end of her life around the time the young hatch.
  - Studies of another octopus species suggest that hormones from small glands near the eyes, the optic glands, switch on this last stage of life.
- **Arm Regrowth** (weeks–months to regrow an arm): If an arm is badly damaged or lost, a common octopus can grow a new one, with muscles and nerves. [4][16][17]
  - A lost arm grows back within weeks to months.
  - Scientists have studied regrowth in cephalopods for over 160 years, in more than 100 studies.
  - The common octopus is a model animal for this research, and microscopes are used to follow how the new arm forms.
  - Unlike some octopuses, it has no built-in breaking point for dropping an arm on purpose.

### Body parts

- **Eyes** (1 type of light-sensing cell) [1][2][3][4]
  - Each eye has a horizontal, slit-shaped pupil.
  - The eyes have only one type of light-sensing cell. In tests, common octopuses told shades apart by brightness, but not by colour.
  - Octopuses can detect polarised light, which may help them spot prey or predators in sunlit water.
- **Brain** (≈500 million nerve cells in all) [4][5]
  - The brain is a ring around the gullet (oesophagus), so swallowed food passes through the middle of it.
  - About 130 million nerve cells sit in the two optic lobes behind the eyes, and only about 40 million in the rest of the brain.
  - Counting the arms too, a common octopus has about 500 million nerve cells, and about 300 million of them are in the arms.
  - Scientists think the strong beak and toothed tongue may have evolved because food must pass through the brain ring in small pieces.
- **Arms** (4–5½× as long as the mantle) [4][5][6]
  - Eight arms, each 4 to 5½ times as long as the mantle. The third pair is usually the longest.
  - A web of skin joins the arm bases.
  - About 300 million nerve cells run through the arms, so each arm handles much of its own movement and touch.
  - In males, the third right arm is a little shorter, with a special tip used for mating.
- **Suckers** (220–320 suckers per arm) [4][7][8]
  - Two rows of suckers run under each arm: about 220 to 320 per arm in a large octopus, or roughly 2,000 in all.
  - Two or three suckers on the side arms are extra large, more so in males.
  - Suckers grip wet and even rough surfaces, because their soft tissue moulds to the shape of the surface.
  - Suckers also taste what they touch. In a close relative, the California two-spot octopus, scientists found “taste-by-touch” receptors in sucker cells.
- **Siphon** (2 jobs jetting and inking) [4][9]
  - The siphon (funnel) is a tube that sticks out of the opening of the mantle, under the head.
  - Squirting water hard out of the siphon shoots the octopus backwards: jet propulsion.
  - Ink from the ink sac leaves through the siphon too.
  - Even 1–2 mm hatchlings swim by jet propulsion.
- **Skin** (3 kinds of colour organs) [4][10]
  - The skin has three kinds of colour organs: chromatophores (yellow, orange, red, brown and black pigment sacs), shiny iridophores and white leucophores.
  - Each chromatophore is an elastic pigment sac pulled open by tiny muscles that are wired to the brain. That is why colours can change so fast.
  - The common octopus can raise four large skin bumps (papillae) in a diamond on its back, and one or two over each eye.
  - A pair of white spots on the back of the mantle is a common-octopus feature.
- **Hearts** (3 hearts) [4][11]
  - Three hearts: one main (systemic) heart pumps blood round the body, and two gill hearts push blood through the gills.
  - The blood is blue because it carries oxygen with haemocyanin, a copper-based pigment.
  - At rest, the main heart of a 500 g common octopus beats about 40–50 times a minute (at 22 °C). When the octopus is busy, the heart pumps more blood per beat rather than beating much faster.
- **Beak** (1 big hard part in the body) [4][12]
  - In the middle, under the arms, is a hard, parrot-like beak made of chitin, plus a toothed tongue called a radula.
  - Its saliva contains toxins and enzymes that quickly calm crabs and fish and start to digest them.
  - To get into shellfish, it can drill a tiny hole with toothed bumps near the radula and soften the shell with saliva.
  - There is no skeleton, and the old mollusc shell is reduced to two tiny rods. That leaves the beak as the main hard part.
- **Den** (By day time spent in the den) [4][13][14]
  - Common octopuses spend most of the day in a den: a crack in the rocks, or a hollow they make in sand or mud, sometimes with stones and shells.
  - On soft seabeds, a shortage of den-building material can limit where they live.
  - Shells and crab remains pile up outside as a midden. But young octopuses eat about 30% of their prey away from home, and waves wash small remains away.
  - They are mostly active at night, from the shore down to about 250 m, but usually in water shallower than 100 m.

### Stats

| Stat | Value | Notes |
|---|---|---|
| Mantle length | up to 40 cm | commonly about 25 cm [4] |
| Total length | ≈1.8 m max | the arms are 4–5½ times as long as the mantle [4] |
| Weight | over 20 kg | the largest known; most are much smaller [4] |
| Suckers | 220–320 per arm | in two rows, in larger animals; Roughly 2,000 suckers in all [4] |
| Nerve cells | ≈500 million | about 300 million of them in the arms; 3 out of every 5 are in the arms [5] |
| Hearts | 3 | 1 main heart and 2 gill hearts, pumping blue blood [4] |
| Resting heartbeat | 40–50 per min | a 500 g octopus at 22 °C [11] |
| Eggs per brood | 100,000–500,000 | each about 2 mm long [4] |
| Lifespan | 1–2 years | females breed once [4] |
| Depth | 0–250 m | usually shallower than 100 m [4] |

### Photos

- [Hiding in a rock crack near Plakias, Crete, Greece](https://commons.wikimedia.org/wiki/File:Common_octopus.jpg) (photo: Martijn Klijnstra, CC BY-SA 4.0)
- [A mother octopus with her eggs](https://commons.wikimedia.org/wiki/File:Polpo_Femmina_con_uova_2009-08-12.jpg) (photo: Ruggero Caravita, CC BY-SA 3.0)
- [An eye up close](https://commons.wikimedia.org/wiki/File:Dettaglio_dell'occhio_di_un_polpo.jpg) (photo: Federico Stefanelli, CC BY-SA 4.0)
- [Medes Islands marine reserve, Costa Brava, Spain](https://commons.wikimedia.org/wiki/File:Common_octopus_(Octopus_vulgaris)%2C_Pedra_de_Deu%2C_Medes_Islands%2C_Spain.jpg) (photo: Jouni Kuisma, DiveCodex, CC BY-SA 4.0)
- [Moneglia, Liguria, Italy](https://commons.wikimedia.org/wiki/File:Gew%C3%B6hnlicher_Krake_Octopus_vulgaris_1.jpg) (photo: Holger Krisp, CC BY 4.0)
- [Blue Lagoon, Akamas Peninsula, Cyprus](https://commons.wikimedia.org/wiki/File:Octopus_(28836592458).jpg) (photo: Ansgar Gruber, CC BY-SA 2.0)
- [Cathedral Cave, Gozo, Malta](https://commons.wikimedia.org/wiki/File:Pulpo_com%C3%BAn_(Octopus_vulgaris)%2C_Cathedral_Cave%2C_Gozo%2C_Malta%2C_2021-08-23%2C_DD_27.jpg) (photo: Diego Delso, CC BY-SA 4.0)
- [Arrábida, Atlantic coast of Portugal](https://commons.wikimedia.org/wiki/File:Pulpo_com%C3%BAn_(Octopus_vulgaris)%2C_Parque_natural_de_la_Arr%C3%A1bida%2C_Portugal%2C_2022-07-29%2C_DD_22.jpg) (photo: Diego Delso, CC BY-SA 4.0)
- [Teno-Rasca, Tenerife, Canary Islands](https://commons.wikimedia.org/wiki/File:Pulpo_com%C3%BAn_(Octopus_vulgaris)%2C_franja_marina_Teno-Rasca%2C_Tenerife%2C_Espa%C3%B1a%2C_2022-01-05%2C_DD_128.jpg) (photo: Diego Delso, CC BY-SA 4.0)

### Questions

- **How many hearts does an octopus have?** Three. Two gill hearts pump blood through the gills, and one main heart pumps it round the body. At rest, the main heart of a 500 g common octopus beats about 40–50 times a minute. [4][11]
- **How smart is the common octopus?** Very good at solving practical problems. In lab tests, common octopuses learned to pull the plug out of a glass jar to reach a crab and got faster with practice. A famous 1992 study found that octopuses that watched a trained octopus then picked the same ball (red or white), but it was a single study, and scientists still discuss how much octopuses learn by watching. Using coconut shells as shelters was seen in a different species, the veined octopus. [22][34][20]
- **How many suckers does a common octopus have?** A large common octopus has about 220–320 suckers in two rows on each arm, roughly 2,000 in all. The suckers grip wet, rough rock and can taste what they touch. [4][7][8]
- **Can octopuses see colour?** Probably not. Their eyes have only one type of light-sensing cell, and in tests common octopuses told shades apart by brightness, not colour. Scientists are still working out how they match their surroundings so well; their skin may sense light too. [4][2][3][26][27]
- **How long does a common octopus live?** About 1–2 years. Females breed only once: a mother guards her eggs for weeks or months, stops eating, and dies around the time they hatch. [4]
- **Is the common octopus dangerous to humans?** No. Like other octopuses it has venomous saliva for subduing crabs and fish, but it is not dangerous to people. Bites are rare and usually happen when someone handles a freshly caught octopus. A bite can hurt and, rarely, get infected, so tell an adult and see a doctor. Never touch octopuses in the wild: blue-ringed octopuses carry a toxin that has killed people. [4][12][35]
- **Where does the common octopus live?** Octopus vulgaris lives in the Mediterranean Sea and the eastern Atlantic, from the south coast of England to West Africa, the Azores, the Canary Islands and Cape Verde. It lives on rocky, sandy or muddy seabeds from the shore to about 250 m deep. Similar octopuses elsewhere are now treated as separate species. [4][23]
- **How does a common octopus hunt?** Mostly at night. It probes cracks and the spaces under rocks with its arms, or wraps a rock in its arms and web and flushes out prey with its arm tips. It catches crabs, lobsters, fish and shellfish, and can drill or prise shells open. [4][14]

### Common octopus: myth or fact?

Octopuses attract tall tales. Here is what the evidence says.

- "An octopus has eight tentacles." **Myth!** They are arms. Squids and cuttlefish have eight arms plus two long feeding tentacles; octopuses have only the eight arms. [4][19]
- "Octopuses have three hearts and blue blood." **Fact!** Two gill hearts pump blood through the gills and one main heart pumps it round the body. The blood is blue because its oxygen carrier, haemocyanin, is based on copper. [4]
- "An octopus has nine brains." **Myth!** It has one ring-shaped brain. But about 300 million of its 500 million nerve cells are in the arms, which control much of their own movement. That is where the “nine brains” nickname comes from. [4][5][6]
- "Octopuses see the colours they copy." **Myth!** Their eyes have only one type of light-sensing cell, and in experiments common octopuses told shades apart by brightness, not colour. They seem to match brightness, pattern and texture instead. Exactly how they blend in so well is still being studied. [4][2][3][1]
- "The common octopus carries coconut shells to hide in." **Myth!** That is the veined octopus (Amphioctopus marginatus) of Indonesia, which carries coconut-shell halves and uses them as a shelter. The common octopus hides in rock cracks and in dens it makes, sometimes with stones and shells. [20][4][13]
- "The common octopus disguises itself as a sea snake or a lionfish." **Myth!** That is the mimic octopus, a different species found in Indonesia. The common octopus hides mainly by blending in with its background. [21][4]
- "An octopus can open a jar to get the crab inside." **Fact!** In experiments, common octopuses pulled the plug out of glass jars to reach a live crab, and they got better with practice. [22]
- "The common octopus lives in oceans all over the world." **Myth!** It used to be thought of as worldwide. Body and DNA studies now show that look-alikes in the western Atlantic (Octopus americanus and O. insularis), south-west Australia (O. djinda) and other places are separate species. Octopus vulgaris itself lives in the Mediterranean and eastern Atlantic. [4][23][24][25]

### Common octopus records

Big numbers and record holders, each checked against its source.

- World’s biggest one-species octopus fishery: Common octopus off northwest Africa, ≈58,000 t (Africa’s octopus catch in 2010, almost all of it this species; Morocco landed about 32,000 t) [4]
- Biggest egg brood: Common octopus mother, up to 500,000 (eggs in strings on the roof of her den) [4]
- Longest guard duty: Common octopus mother, up to 4–5 months (guarding her eggs without feeding, in cool water) [4]
- Nerve cells outside the brain: Common octopus arms, ≈300 million (3 in every 5 of its nerve cells are in the arms) [5]
- Biggest on record: Common octopus, over 20 kg (with a total length of up to about 1.8 m) [4]
- Sucker count: Common octopus, ≈2,000 (220–320 suckers on each arm of a large octopus) [4]

### A common octopus’s life

From a 2 mm egg to a seabed hunter and parent in just one or two years.

- **Day 0**: An egg on a string. The mother hangs her eggs, each about 2 mm long, in strings from the roof of her den. [4]
- **Weeks to months**: Guarded. She cleans the eggs and blows fresh water over them. They hatch faster in warm water and can take 4–5 months in cool water. [4]
- **Hatching**: A tiny drifter. Hatchlings are 1–2 mm long and see-through, with short arms and few suckers. They swim straight up into open water as plankton. [4]
- **Weeks to months**: Night swimmer. The young (paralarvae) jet about, rise towards the surface at night, stay deeper by day and eat young crustaceans. [4]
- **Settling**: Down to the seabed. They settle, change into a small adult shape with many suckers and patterned skin, and start a hidden life on the seabed. [4]
- **Growing up**: Den and dinner. Young octopuses find dens and hunt crabs and shellfish by touch and taste, mostly at night. [4][14]
- **About 1 year**: Grown up. Adults mate with several partners, and there are no couples. A female keeps the male’s sperm packets until she is ready to lay her eggs. [4]
- **1–2 years**: A short life. A mother stops eating while she guards her eggs and dies around the time they hatch. Common octopuses live about 1–2 years. [4]

### How the common octopus hides

Colour-blind eyes, yet some of the best camouflage in the sea. These are the parts that make it work.

- **3** kinds of colour organs. Chromatophores hold yellow, orange, red, brown or black pigment. Iridophores add shine, and leucophores reflect white light. [4]
- **Nerves** not hormones. Each chromatophore is opened by tiny muscles wired to the brain, so patterns can change very fast and very finely. [10]
- **4** big bumps on the back. Four large papillae in a diamond on the back, plus one or two over each eye, can be raised to copy rough rock and weed. [4]
- **1** type of light-sensing cell in the eye. In tests, octopuses tell shades apart by brightness, not colour. Their camouflage seems to match brightness and pattern rather than exact colours. [4][2][3][1]
- **Skin** that senses light. Skin of the California two-spot octopus reacts to light by itself, and a light-sensing gene is active in common octopus suckers and skin. How much this helps camouflage is not yet known. [26][27]

One idea, from a computer model, is that the octopus’s slit pupil could let it pick up colour from tiny differences in blur. It has not been shown in living octopuses.

### Common octopus vs squid vs cuttlefish

All three are cephalopods with ink and big brains, but their bodies are built differently.

| | Common octopus | Squid | Cuttlefish |
|---|---|---|---|
| Arms and tentacles [4][19] | 8 arms | 8 arms + 2 long feeding tentacles | 8 arms + 2 long feeding tentacles |
| Shell inside [4][19] | None, or 2 tiny rods (stylets) | Usually a thin pen (gladius) | A chambered shell (cuttlebone) |
| Suckers [4][19] | Sit right on the arm | On stalks, with horny rings | On stalks, with horny rings |
| Pupil shape [1] | Horizontal slit | U-shaped (shallow-water squids) | U-shaped |
| Eggs [4] | Mother guards and cleans them | Wrapped in jelly | Wrapped in jelly |
| Ink [9] | Yes | Yes | Yes |

The squid and cuttlefish columns describe each group in general; individual species vary.

### Is the common octopus endangered?

No. It is widespread and common, but it is also one of the most heavily fished octopuses in the world.

- **IUCN Red List:** Least Concern (LC) (Trend unknown). Common in the Mediterranean and eastern Atlantic. Numbers can rise and fall a lot from year to year. [28][29][4]
- IUCN Red List (via Wikidata and GBIF)
- **Threat: Heavy fishing** (≈58,000 t): It is caught by everyone from hobby fishers to big fleets. Off northwest Africa it supports the world’s largest single-species octopus fishery, where falling catches have been reported. [4]
- **Threat: Boom-and-bust years**: Babies drift as plankton for weeks or months, so currents and sea conditions strongly affect how many young octopuses arrive each year. [4]
- **Helping: Counted as sentient** (2022): The UK’s Animal Welfare (Sentience) Act 2022 includes all cephalopods, such as octopuses, in its definition of animals. [30]
- **Helping: The farming debate** (2024): Because the common octopus is so valuable, researchers and companies, especially in Spain, have worked on farming it, although raising the tiny hatchlings has proved hard. Some scientists argue against octopus farming, because octopuses eat other animals and are behaviourally complex. In 2024, Washington State in the USA banned octopus farming. [4][31][32][33]

### Looks

- **Mottled red-brown**: Blotchy brown, red-brown and cream patches over bumpy skin, a mix that blends into rock and weed. (Everyday camouflage) [4][10]
- **Pale**: When the chromatophore muscles relax, the pigment sacs shrink to dots and the white leucophores show through, so the skin turns pale cream or grey. (Sleeping octopuses of a related species turn evenly pale) [10][4][18]
- **Dark red**: With the red and brown chromatophores pulled wide open, the skin turns a deep red-brown. (Pigment sacs fully open) [10][4]
- **Mother with eggs**: A female in her den, with strings of tiny eggs hanging from the roof. She stays with them for weeks or months. (Her one and only brood) [4]

### Common octopus quiz

1. How many hearts does a common octopus have? **3.** One main heart and two gill hearts. [4]
2. What makes octopus blood blue? **Haemocyanin, a copper-based pigment.** Haemocyanin carries oxygen and contains copper. [4]
3. How many suckers are on each arm of a large common octopus? **About 220–320.** About 220–320 per arm, so roughly 2,000 in all. [4]
4. Where are about 300 million of its 500 million nerve cells? **In the arms.** About 3 in every 5 nerve cells are in the arms. [5]
5. What shape is the octopus brain? **A ring around the gullet.** Food passes through the middle of the ring-shaped brain. [4]
6. What is a pseudomorph? **A dark ink blob that looks roughly like a cephalopod.** Thick, mucus-rich ink can form a decoy blob. [9]
7. Which octopus carries coconut shells to use as a shelter? **Veined octopus.** The veined octopus of Indonesia, not the common octopus. [20]
8. In colour tests, what could common octopuses tell apart? **Brightness, but not colour.** Their eyes have only one type of light-sensing cell. [2][3][4]
9. How many eggs can a common octopus mother lay? **100,000–500,000.** She hangs them in strings from the roof of her den. [4]
10. How long does a common octopus usually live? **1–2 years.** It lives fast and dies young: about 1–2 years. [4]
11. Where does Octopus vulgaris live, by today’s science? **The Mediterranean and eastern Atlantic.** Look-alikes elsewhere are now treated as separate species. [4][23]
12. What is the main hard part of an octopus’s body? **Its beak.** With no skeleton, only the beak (and two tiny rods) are hard. [4]

### Sources (checked 2026-10-16)

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11. [Wells MJ (1979). The heartbeat of Octopus vulgaris. Journal of Experimental Biology 78:87–104.](https://doi.org/10.1242/jeb.78.1.87)
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14. [Mather JA (1991). Foraging, feeding and prey remains in middens of juvenile Octopus vulgaris (Mollusca: Cephalopoda). Journal of Zoology 224:27–39.](https://doi.org/10.1111/j.1469-7998.1991.tb04786.x)
15. [Wodinsky J (1977). Hormonal inhibition of feeding and death in octopus: control by optic gland secretion. Science 198:948–951.](https://doi.org/10.1126/science.198.4320.948)
16. [Imperadore P, Fiorito G (2018). Cephalopod tissue regeneration: consolidating over a century of knowledge. Frontiers in Physiology 9:593.](https://doi.org/10.3389/fphys.2018.00593)
17. [Imperadore P, Galli R, Winterhalder MJ, Zumbusch A, Uckermann O (2022). Imaging arm regeneration: label-free multiphoton microscopy to dissect the process in Octopus vulgaris. Frontiers in Cell and Developmental Biology 10:814746.](https://doi.org/10.3389/fcell.2022.814746)
18. [Medeiros SLS, Paiva MMM, Lopes PH, Blanco W, Lima FD, Oliveira JBC, et al. (2021). Cyclic alternation of quiet and active sleep states in the octopus. iScience 24:102223.](https://doi.org/10.1016/j.isci.2021.102223)
19. [Young RE, Vecchione M, Mangold KM. Decapodiformes. Tree of Life Web Project.](http://tolweb.org/Decapodiformes/19404)
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21. [Norman MD, Finn J, Tregenza T (2001). Dynamic mimicry in an Indo-Malayan octopus. Proceedings of the Royal Society B 268:1755–1758.](https://doi.org/10.1098/rspb.2001.1708)
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## Measurements & details

- **Size:** 30 cm
- **Weight:** 5 kg
- **Lifespan:** 1 years
- **Arm Count:** 8
- **Number Of Hearts:** 3

## Diet & Feeding

Octopuses are clever predators, feasting on crabs, clams, and small fish in the ocean.

- **Primary Foods:** crabs, lobsters, clams, snails, small fish
- **Foraging Method:** Foraging

## Ecological connections

- **Eaten by:** [Tiger Shark](https://www.snappit.app/explore/tiger-shark) (*Galeocerdo cuvier*) — Sharks are among the predators of octopuses.
- **Eaten by:** [Bottlenose Dolphin](https://www.snappit.app/explore/bottlenose-dolphin) (*Tursiops truncatus*) — Dolphins hunt octopuses.
- **Eaten by:** Mediterranean Moray (*Muraena helena*) — Moray eels are skilled octopus hunters.

## Traits

- [Solitary](https://www.snappit.app/explore/traits/solitary): Solitary animals live alone for most of their lives, only interacting with others for mating or parental care.
- [Camouflaged](https://www.snappit.app/explore/traits/camouflaged): Camouflaged describes organisms that possess coloring or patterns that allow them to blend into their environment.
- [Tool Use](https://www.snappit.app/explore/traits/tool-use): This trait describes organisms that manipulate external objects to achieve a specific goal.
- [Carnivorous](https://www.snappit.app/explore/traits/carnivorous): This trait identifies organisms whose diet consists entirely or primarily of animal tissue.
- [Keystone Species](https://www.snappit.app/explore/traits/keystone-species): Describes a species whose presence and role have a disproportionately large effect on its environment.
- [Regenerative](https://www.snappit.app/explore/traits/regenerative): Regenerative organisms possess the ability to regrow lost or damaged body parts, tissues, or organs.
- [Marine](https://www.snappit.app/explore/traits/marine): Marine habitats encompass all saltwater environments of the Earth's oceans, supporting an immense diversity of aquatic life.
- [Nocturnal](https://www.snappit.app/explore/traits/nocturnal): Nocturnal animals are primarily active during the nighttime hours, typically resting or sleeping during the day.
- [Venomous](https://www.snappit.app/explore/traits/venomous): Venomous organisms produce toxins that are injected into another animal, typically through a bite or sting.

## Collections

- [Invertebrates](https://www.snappit.app/explore/collections/invertebrates)

## Safety

**Danger:** 2/5 · Low

Always observe octopuses from a safe distance and never touch them in the wild.

## Frequently Asked Questions

### How to identify Common octopus?

Look for fins, arms, tentacles, shells and body symmetry. Underwater light shifts colors, so structure and markings usually matter more than shade. Sea Creature Identifier: upload a photo and compare the visible details.

### How big is Common octopus?

30 cm

### How much does Common octopus weigh?

5 kg

### How long does Common octopus live?

1 years

### What does Common octopus eat?

Octopuses are clever predators, feasting on crabs, clams, and small fish in the ocean.

### Where is Common octopus usually found?

Marine

### How many arms does Common octopus have?

8

## Where to spot

- [Akron Zoo](https://www.snappit.app/guides/places/akron-zoo) — Ohio, US · Zoo
- [Greater Cleveland Aquarium](https://www.snappit.app/guides/places/greater-cleveland-aquarium-ohio) — Ohio, US · Aquarium
- [Milwaukee County Zoo](https://www.snappit.app/guides/places/milwaukee-county-zoo) — Wisconsin, US · Zoo
- [Shedd Aquarium](https://www.snappit.app/guides/places/shedd-aquarium) — Illinois, US · Aquarium
- [Belle Isle Aquarium](https://www.snappit.app/guides/places/belle-isle-aquarium) — US · Zoo
- [Long Island Aquarium and Exhibition Center](https://www.snappit.app/guides/places/long-island-aquarium-and-exhibition-center-new-york) — New York, US · Zoo

[View all places to see Octopus](https://www.snappit.app/guides/where-to-see/octopus)

## More Invertebrate

- [Coral](https://www.snappit.app/explore/coral)
- [Crab Spider](https://www.snappit.app/explore/crab-spider) (*Mecaphesa asperata*)
- [Garden Spider](https://www.snappit.app/explore/garden-spider) (*Araneus diadematus*)
- [Brown Recluse Spider](https://www.snappit.app/explore/brown-recluse-spider) (*Loxosceles reclusa*)

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Source: [Common octopus: Facts & Places to See — Snappit](https://www.snappit.app/explore/octopus)