Southern Sand Octopus

Octopus kaurna

You could swim right past a southern sand octopus and never even realize it! They’re masters of hiding themselves in the soft seafloor. They can both bury themselves and burrow with ease! 

To burrow, the sand octopus blasts water down into the seafloor to make it easier to wiggle down into the sand. Then when it’s fully underground, it makes a “chimney” through the sand so it can breathe!

Size

16.5 in long (42 cm)

Lifespan

Unknown

Habitat

Shallow seas — sand, mud, and seagrass habitats

Diet

Crustaceans

Range

Temperate seas around southern Australia

Predators

Unknown

superpower

Sand-Shaping

This octopus can shoot out a powerful jet of water to turn regular sand into quicksand!

SCIENTIFIC NAME: Octopus kaurna

This species was named and described in 1990! The name kaurna is derived from an Australian Aboriginal clan that inhabited the Adelaide Plains of South Australia.

Sand Octopus Photos by Sam Glenn-Smith

SIZE OF THE SAND OCTOPUS

The southern sand octopus is a small to medium sized octopus with a mantle length to 85 mm (3.5 in) and a total length to around 420 mm (16.5 in). It has a wide head (slightly narrower than the mantle) with small eyes that do not protrude far above the surface of the head. It’s arms are extremely long (3-6x the mantle length in mature animals) with small suckers and a shallow web. Its funnel is large and slender. Check out the behavior section to find out how this animal uses its long arms and large funnel!

SAND OCTOPUS LIFESPAN

unknown

DISTRIBUTION

This species is found in the temperate waters of southern Australia from eastern Victoria and northern Tasmania and west to the Great Australia Bight.

HABITAT

This is benthic, shallow-water species that lives in coastal waters to depths of around 50 m (164 ft). It can be found on sand, mud, or seagrass beds and is able to create sub-surface burrows for its den!

DIET

The southern sand octopus remains buried during the day in its burrow and emerges at night to feed on small crustaceans by probing its thin arms down burrows and holes!

BODY PATTERNS AND BEHAVIORS

The base color of the southern sand octopus can range from orange-cream to maroon-red. The skin texture is generally smooth or covered with numerous tiny bumps known as epidermal tubercles. These bumps are usually largest on the dorsal surface and less noticeable on the ventral surface of the octopus. This is one species without large papillae over the eyes (aka supraocular papillae)! When foraging, it can have a pink base color with an elongated mantle that has a dark maroon stripe on each side of its mantle.  The mantle stripes can extend across the eye to the arm tips.

CAN YOU DIG IT?

Only a small number of cephalopods use the two behaviors burying and burrowing. Yes, there is a difference! Burying is considered the superficial covering with sediment while burrowing is the active movement through soft substrates where the substrate (like sand) is displaced and the surrounding substrate is often altered. 

In a sandy environment where there is no place to hide from predators this species
creates a predator proof bunker! But, how do they do this? A team of scientists in 2015 reported the first detailed study of how the southern sand octopus burrows and how it can breathe while residing in this bunker.  The scientists observed octopuses burrowing in the wild and set up laboratory experiments to closely examine the burrowing mechanisms and if different sizes of sand (fine to medium, course, very course) influenced octopus burrowing.


Scientists created an “ant farm” style aquarium to see how this sand-dwelling octopus burrows and it
turns out there are 4 stages for the southern sand octopus to create its burrow!

First, the octopus produces its own quicksand!
Burrowing begins with the octopus directing its funnel downwards and fully expanding its mantle in preparation for expelling the first jet of water into the sediment. The jetting action of the mantle and siphon inject water into the sediment which temporarily suspends the sand grains in the water or “fluidizes” the sand grains. This increases burrowing effectiveness by reducing drag and the energy needed for burrowing.

Second, the octopus moves its arms in the quicksand while its mantle and funnel remain above the surface to continue the jetting action. Once the underlying sediment is fluidized, the octopus pulls the rest of its body under the surface!

Next, the octopus uses its arms and expanded mantle to push the surrounding sediment away from its body to burrow deeper.
Scientists reported the octopus’s burrow ranged from 3-11 cm (1-4 in) from the surface and octopuses burrowed slowest in very coarse sediment because the larger grain size likely requires more effort in fluidization.

After burrowing deeper, the octopus extends two arms to the surface to create a ventilation chimney! Finally, the arms are retracted and there is one last strong exhalation that pushes any loose sand from the chimney. To maintain the burrows structure, the octopus lines the chimney with mucus!
 

It is also possible that the females release a pheromone (sexually-attractive chemical) out of their burrow’s chimney! Groups of males have been observed swarming over a single female. Females lay large eggs (9-11mm or ½ in long) that they attach singly to hard surfaces. Once the large young hatch, they are immediately benthic and head into the sand. 

 

This burrowing octopus species provides insight into the possible ecology of other sand-dwelling octopuses whose burying or burrowing behaviors have yet to be explored!  

 

  • Stranks, T. (1990) Three new species of octopus (Mollusca: Cephalopoda) from South-Eastern Australia. Memoirs of the Museum of Victoria 50:457-465. 
  • Jereb, P.; Roper, C.F.E.; Norman, M.D.; Julian K Finn (eds). Cephalopods of the world. An annotated and illustrated catalogue of cephalopod species known to date. Volume 3. Octopods and Vampire Squids. FAO Species Catalogue for Fishery Purposes. No. 4, Vol. 3. Rome, FAO. 2014. 370 p
  • Montana, J., Finn J., Norman M. (2015) Liquid sand burrowing and mucus utilization as novel adaption to a structurally-simple environment in Octopus kaurna Stranks, 1990. Behaviour 152:1871-1881. 
  • Finn, J. and Norman M. (2018). Octopus kaurna Soutern Sand Octopus in Museums Victoria https://collections.museumsvictoria.com.au/species/8697

Book Giveaway: “Secrets of the Octopus” & Bonus interview!

[Update 3/18/24: Submissions Closed] 🐙 🎉 OctoNation is beyond thrilled to offer our community a chance to win one of the newest National Geographic octopus books to hit the shelves next week, “Secrets of the Octopus” by the New York Times Bestseller of “The Soul of an Octopus”, Sy Montgomery & Founder of OctoNation, Warren

Read More »

‘Artist Spotlight’ Of The Week: Victor Grasso

Howdy Nation! Buckle up for today’s adventure as we shine the ‘Artist Spotlight’ on Victor Grasso, an artist who explores the relationship between humans and octopuses. Join us as we celebrate his captivating & playful series—a journey we never want to end! Who is Victor Grasso? I am an internationally represented artist showing with galleries

Read More »
view of a cockeyed squid in blue light with a glowing giant eye

Meet the Cockeyed Squid: the Deep-Sea Animal with a Giant Eye!

Get ready to meet the dazzling, one-of-a-kind Histioteuthis heteropsis, affectionately known as the “Cockeyed Squid” (because of it’s mismatched eyes) or “Strawberry Squid” ( cuz of its deep red pigmentation and photophores resembling strawberry seeds​) The species name “heteropsis” is derived from Greek, with “hetero” meaning ‘different’ and “opsis” meaning ‘sight’ or ‘eye’. Thus, “heteropsis”

Read More »

‘Cephalotography’ Of The Week: Jialing Cai

Dive into moonlit waters with OctoNation alongside Jialing Cai, an award winning underwater photographer from Chongqing, China, whose tales may just spark the beginning of your scuba adventure! Discover the challenges and joys of capturing the elusive octopus and other cephalopods. Ready? Let’s go! How long have you been an underwater photographer? How did you

Read More »

10 Facts About Baby Nautilus!

🔘 Googly eyed and barely bigger than a cherry 🍒 is how a baby nautilus bursts into the ocean scene to start its life. The nautilus is a hard-shelled cephalopod that has been around since long before dinosaurs, mammals, and insects, which means it once shared the ocean with the megalodon (the largest shark that

Read More »

Book Giveaway: The Lives of Octopuses and Their Relatives

🐙 🎉 OctoNation is beyond thrilled to offer our community a chance to win one of the newest octopus books to hit the shelves— and it’s a BIG ONE (nearly 300 pages!) Simply enter your name and email address to register & learn even more about the Lives of Octopuses and Their Relatives below! Book

Read More »
Skip to content