Key Takeaways on Octopus Arms
- Octopuses typically have eight limbs that are called arms. Because the limbs have suction cups for its entire length, they are called arms instead of tentacles.
- Octopus arms can help the sea creatures hunt, move heavy objects – each sucker can lift 30 pounds – and escape.
- Depending on the species, an octopus can regrow a limb within a few months. Giant Pacific octopuses, for example, can regrow a third of their limb within six weeks.
Many workers have balled up their fists in frustration over a lazy, do-nothing coworker. Octopuses also appear to know that feeling.
In 2024, researchers observed the day octopus hunting with fish partners in the Red Sea. As the blue goatfish helpfully sniffed out hidden food, the blacktip groupers were moochers. When enough was enough, the octopus punched a grouper with its arm.
The punch surprised scientists (and maybe impressed them too). Increasingly, researchers are learning that octopus arms are strong and capable of doing many things.
Octopus Arms Have Strong Suckers
Octopuses typically have eight arms that are lined with suction cups. In the wild, octopuses like the giant Pacific octopus (GPO) rely on their strength for survival. Each sucker can lift 30 pounds, and a GPO has 1,600 suckers. Their arms can also pull 100 times their weight, which means a 40 pound octopus can pull 4,000 pounds — the size of a small sedan.
Obviously, cephalopods have little need to pull cars. So what is their strength good for?
“The majority of their sucker’s strength is spent on a variety of diet items, including hard shelled crabs, clams, and mussels,” says Jordan Baker, a senior aquarist in the Northern Waters Gallery at the New England Aquarium in Boston. “Their strong suckers can help in prying open these shellfish. They also hunt fishes and other smaller cephalopod species, and strong suction helps with subduing prey effectively.”
Read More: Octopuses Partner with Fish to Hunt, and Will Slap the Fish That Slacks Off
Octopus Arms Help Them Hunt and Escape
Their arms are also highly dexterous. In a 2025 study in Nature Communications, researchers analyzed the cellular and molecular structure of the California two-spot octopus. They found that the axial nerve cords are segmented, which means octopuses can move each sucker independently.
Octopus arms are also very flexible. In a 2020 study in Scientific Reports, researchers observed the California two-spot octopus making 16,500 arm “deformations” in a two-hour time period. With these deformations, the octopus made movements like bending, elongating or shortening.
“In the wild, this is meant to help them hunt for prey,” Baker says.
In captivity, an octopus’s flexibility and dexterity means they are escape artists. Habitats need tightly-sealed lids or the eight-armed resident may entertain themselves by finding an exit.
At the New England Aquarium, Baker says they have a GPO named Tako. They keep him amused with puzzle boxes. Each box has different layers that he has to manipulate and open to receive the fishy reward inside.
“Their arms have more strength underwater than above, and with the strength of their suckers they are able to grip and manipulate until the final treat at the center is received,” Baker says.
Can Octopuses Regrow Their Limbs?
At the aquarium, it’s unlikely that Tako will ever be injured by a predator or a rival and lose a limb.
But it’s a common occurrence for those living in the wild, and most octopuses will experience some sort of arm injury in their lifetime.
Octopuses are capable of regrowing a missing tentacle. Within days of losing a limb, the skin where the arm used to be will regain the ability to change colors and patterns. After two weeks, nerve regeneration is noticeable.
Depending on the species, an octopus can regrow a limb within a few months. GPOs, for example, can regrow a third of their limb within six weeks.
Rapid growth (and regrowth) is standard for most octopus species due to their short lifespans. Whereas sharks, sea turtles and whales are known to live for decades, octopuses live for just a few short years – assuming they even make it to adulthood. The GPO is one of the longer living species and it only lives for three to four years.
Baker says she has witnessed such phenomenal growth with the octopuses at her aquarium. “Our GPOs come in around 10 to 15 pounds in weight,” she says. “It only takes them a year to gain an additional 50 to 60 pounds.”
Read More: Octopus Suckers Inspire New Grippy Material to Help Grab Objects
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