Outforia Quicktake: Key Takeaways
- Common octopus are found in Mediterranean Sea, Eastern Atlantic Ocean, and Japanese waters
- Has a large head and eight arms; can change color to blend in with surroundings
- Highly intelligent, can learn tasks and recognize species including humans
- Lives in deep ocean habitats, typically ranging from 3,300-13,100 ft (1,005-3,993 m) in depth
- Diet consists of crustaceans, bivalves, and gastropods; adults weigh up to 11 pounds (5 kg)
The common octopus is found at the deepest depths of oceans all around the world. It’s one of the most familiar cephalopod species.
The common octopus has a large head, which is attached to its eight arms. These sea creatures have several unique characteristics that allow them to stay hidden amongst their surroundings.
We’re going to take a deep dive into everything you need to know about the common octopus, including its appearance, anatomy, habitat, diet, and special abilities.
What is an Octopus?
The octopus is a type of marine mollusk belonging to the class Cephalopoda.
Octopuses are closely related to other cephalopods, such as squid, cuttlefish, and nautilus. The common octopus (Octopus vulgaris) belongs to the genus Octopus, which is the largest genus of the Octopodidae family.
While scientists and researchers believe there are common octopus subspecies, there aren’t any currently recognized.
Common octopuses are known for having large heads and eight arms that they use to crawl along the seafloor.
Like all cephalopods, the head of the common octopus is attached to its arms. Octopus arms are commonly referred to as tentacles, but tentacles are actually different structures.
You May Also Like: Nocturnal Animals List: What Stays Awake At Night?
Appearance and Size
Common octopuses have eight arms, which are used for feeling and tasting. Hundreds of suction disks are located on the underside of common octopus arms. Each sucker can have up to 10,000 nerve cells, which makes them highly sensitive!
Adults have a body weight of up to 11 pounds (5 kg), which is relatively small compared to the over 50-pound giant Pacific octopus.
The common octopus can take on a variety of colors. They can also squeeze into extremely small spaces.
The natural color of common octopuses can range from orange, brownish-tan, or dark amber, red, or light tan to cream. Their bodies are sometimes decorated with light or dark-colored splotches.
Common octopuses have the ability to change their color in a matter of seconds. This ability to camouflage allows them to blend in with their environment or imitate the appearance of objects.
Common octopuses have rectangular pupils located on the head. The bulbous part of the “head” is a separate structure called a visceral mass.
There are many internal structures inside the visceral mass. It contains the ink sac, kidneys, stomach, hearts, gonad, anus, and siphon. A mantle encases all of these internal structures and protects the organs.
So what’s inside of its actual head? The common octopus head includes the skull, brain, buccal mass, beak, and brachial nerve. The skin of common octopuses is smooth and slippery.
Anatomy of the Common Octopus
Common octopuses have three main body part regions, including the arms, head, and visceral mass. The visceral mass holds a wide variety of important internal structures.
Octopuses are capable of secreting ink when threatened. The ink is held in the ink sac within the visceral mass.
Did you know that the common octopus has three hearts? Each of the three hearts serve different purposes. Two of the hearts are used to pump blood directly to the gills to get oxygen. The other heart is used to circulate and pump blood throughout the rest of the body.
The blood of common octopuses is blue. It doesn’t contain iron like human blood. The blue blood is a result of its copper base. Copper-based octopus blood allows these creatures to get oxygen more efficiently since they live in cold deep ocean temperatures.
Most of an octopus’ body is muscle. These marine mollusks actually don’t have bones. One of the hardest structures of the common octopus is the beak. The beak acts as a mouth and is essential for crushing hard-shelled prey, like crabs.
The lack of bones allows octopuses to slip into small caves and crevices found along the ocean floor. This can be especially helpful for escaping from predators.
Most of the neurons an octopus has are actually distributed amongst the arms. The brain located in the head region is the centralized brain. But octopuses also have localized “mini brains” called ganglia in their arms.
The centralized and localized brains work together and make the octopus one of the most intelligent creatures in the deep sea.
Geographic Range and Ocean Zones
Common octopuses are distributed throughout the world in open ocean habitats. They’re most abundant in the Mediterranean Sea, Eastern Atlantic Ocean, and the waters of Japan. They can also be found in other parts of the world in subtropical, tropical, and temperate waters.
The only places where the common octopus isn’t found are the polar and subpolar regions.
Most of the common octopus’ adult life is spent in the benthic zone of the open ocean. The benthic zone is the deepest part of the ocean. It has several sub-zones.
The hadalpelagic zone is the deepest region in the benthic zone.
Most octopuses are found in the bathypelagic zone of the benthic region. It ranges from 3,300-13,100 ft (1,005-3,993 m) in depth. The bathypelagic zone is often referred to as the midnight zone because it’s so dark.
Bioluminescent organisms are the only source of light in this zone. Temperatures are usually below 40°F (4°C).
Common Octopus Habitat
Common octopuses live in holes or crevices. These exploratory creatures search for shells, rocks, and other objects to put around their home for protection.
A common octopus may live in the same home for an extended period of time. Some common octopuses like to change it up and move homes every few days.
This bottom-dwelling species can also be found in coral reefs and seagrass beds.
Juvenile common octopuses spend the early years of their life in coastal waters and near the upper continental shelf. Some adult individuals may participate in seasonal migrations. Breeding patterns largely influence seasonal migrations.
What Does a Common Octopus Eat?
Common octopuses love to eat crustaceans. They use their arms to sense and taste prey. The beak is used to pierce hard-shelled prey.
Other food sources include bivalves and gastropods. Bivalves include various types of mollusks, such as clams, oysters, and mussels. Gastropods include slugs and snails.
Common octopuses use a variety of tactics to hunt their prey. They may use their special color-changing ability to hide and ambush their prey. They’ve also been observed luring prey into their homes. Common octopuses also stalk and pursue prey.
If a common octopus snacks on its prey inside its home, it will discard the remains it doesn’t eat outside the shelter. These discard piles help marine scientists find octopus homes and learn about the common octopus diet.
Baby common octopuses feed on smaller ocean creatures, such as plankton, for the first few months of their life.
Mating and Reproduction
Male octopuses will pursue females for mating purposes. Females will try to fend off males before eventually accepting them to mate.
Common octopuses are polyamorous. Females and males may have multiple partners during breeding season. Some octopuses will mate with the same individuals for up to a week. However, they may pursue or accept other partners during this time.
Female common octopuses choose an egg-laying site. Egg-laying sites are usually in crevices or holes, similar to their homes. Females can lay up to 500,000 eggs per brood! They will stay with their eggs until their babies hatch.
During the brooding process, females take good care of their eggs by cleaning them. Females will also fend off predators that may try to steal any of the eggs.
The brooding period can take as long as five months. During this time, females don’t leave the eggs to feed. They’ll go the entire time without food and lose lots of weight. As a result, females usually die shortly after the eggs hatch.
Females who migrate seasonally may move closer inshore in the spring to spawn.
The lifespan of the common octopus is typically 1-3 years. Males also die shortly after mating.
The survival rate for hatchlings is very low. That’s why so many eggs are laid to increase the chances of hatchling survival. Small juveniles are vulnerable to predation.
You May Also Like: A Deep Dive Into The Intriguing World Of 15 Different Types Of Jellyfish
Special Abilities and Behaviors
The common octopus is incredibly intelligent and has some pretty amazing abilities.
Common octopuses have complex brain systems that allow them to maintain short and long-term memories. They’re also known to be capable of using tools or opening things.
Common octopuses can learn to do tasks, remember locations, and recognize species including humans!
These creatures also have special organs and cells that help them quickly change their color. They have dermal muscles, which are used to texturize the surface of their skin to mimic objects. The skin remains smooth when these muscles are relaxed.
Chromatophores and photophores are two organs that common octopuses have for color change.
Many cephalopods have chromatophores in the epidermis. These organs contain pigments of red, orange, yellow, brown, and black. However, octopuses typically don’t possess all the colors these organs are capable of. Many have an average of 2-3 pigments.
Photophores are blue light-producing organs. Reflector cells help common octopuses turn white or iridescent.
The color cells and organs are controlled by the common octopus’ nervous system. This allows them instant control of their appearance when threatened.
With all these unique features combined, the common octopus is a master of disguise. They can use their color-changing abilities to conceal their shadow, imitate inanimate objects, and resemble their environment.
Conservation Status and Threats
The common octopus was last assessed as least concern in 2016 by the International; Union for Conservation of Nature (IUCN). It’s not considered vulnerable because of its extensive distribution throughout its range.
Common octopuses are threatened by fishing in certain locations. The world population is considered healthy and stable.
Specific population numbers are difficult to determine because of their deep ocean habitat. It’s likely that, along with fishing, common octopuses are threatened by pollutants in the ocean.
Octopuses in Mythology: The Kraken
The kraken is one of the most common depictions of the octopus in a mythological context. The kraken is a giant mythical sea monster that originated from Norway in Scandinavian folklore.
Seeing the kraken was believed to be a message sent by a God or the Devil. Illustrations of the kraken have been drawn throughout history. The large sea monster was believed to lurk the waters of Norway and take down large ships.
Stories of the kraken may be rooted in actual sightings of the giant squid. Giant squids are very large cephalopods. The largest to ever be recorded was 43 ft (13 m) in length. The giant Pacific octopus can also reach great sizes, with the largest individual reaching 30 ft (9 m) in length.
The open ocean still holds many mysteries. More than 80% of the oceans have yet to be mapped out or explored. Although advanced technology has allowed humans to explore more of the ocean than centuries prior, the open ocean still holds many mysteries.
The fear of the unknown and unclear observations of large sea creatures likely fueled these mythological sea creature stories.
You May Also Like: How Long Do Octopus Live? All About Their Unusual Life Cycle
Octopuses can fit in extremely small spaces.
Due to their lack of bones, octopuses can squeeze into tight spaces. This is why they’re often considered master escape artists. Octopuses can likely squeeze through any small crevice that’s as large as their beak.
Octopuses use ink and jet propulsion to escape predators.
Octopuses aren’t super fast movers when they’re using their arms to crawl. However, they can reach higher speeds using jet propulsion to escape enemies. They suck in water that’s stored in the mantle cavity of the visceral mass.
Octopuses use muscle contractions to move the water in a siphon. The water is then quickly expelled from their body to zoom away.
Octopuses also eject ink from their ink sac to create a cloud that confuses predators.
The giant Pacific octopus has the longest lifespan.
Giant pacific octopuses have longer lifespans compared to other octopus species. These giant cephalopods are distributed through the Pacific Ocean. They can live up to 5 years in the wild. Like the common octopus, giant Pacific octopuses don’t live long after mating.
Common Octopus FAQ
Can you eat common octopus?
Octopus is considered a delicacy in various parts of the world. Common octopus may be sought after by commercial fisheries. Overfishing of octopus for food is common in Japan and the Mediterranean.
Which octopus is friendly?
Some octopus species are considered friendly. Their curious nature can be playful. The California two-spot octopus is considered one of the friendliest, or most tolerant, octopuses. They’re distributed along the Pacific coast of North America.
Is it safe to touch an octopus?
Touching an octopus may be dangerous to you or the octopus. Handling small octopuses can cause injury to the octopus. Some octopus can also produce a toxic venom as a defense mechanism. Therefore, you should not touch an octopus unless you’re at an attraction where a wildlife or marine specialist gives permission to do so.
What is an octopus’ worst enemy?
The biggest enemies to octopuses are their predators. A variety of marine animals that live or dive down to the benthic zone feed on octopus. Larger marine species also feed on octopus found in coastal waters. Whales, sharks, and seals are considered the primary predators of octopus.
What is the smartest octopus?
Cuttlefish, squid, and octopus are all considered some of the most intelligent invertebrates in the entire world. Some sources suggest that the octopus is the most intelligent of these three.
A team of Australian biologists from the Museum Victoria conducted a study on the intelligent behaviors of a veined octopus.
The biologists observed the veined octopus collecting and stacking cups and using it as armor for protection. They described the veined octopus as one of the most intelligent animals in the world.
More from Outforia
Check out this other amazing and intelligent octopus species!