Octopus rubescens Berry, 1953  Common name(s): Red octopus
Synonyms:  Octopus pricei
Phylum Mollusca  Class Cephalopoda   Order Octopoda    Family Octopodidae
	Octopus rubescens from intertidal, San Simeon, Ca
	(Photo by: Dave Cowles May 1997).  Caution:  This species often bites!

How to Distinguish from Similar Species: Enteroctopus dofleini is larger (also red), male has a larger hectocotylus (about 1/5 the length of the arm vs 1/10 for O. rubescens (photo)), and its skin has abundant wrinkles along with the papillae.  It is also said that Enteroctopus dofleini does not have the three cirri that are found below the eyes of O. rubescens (photo).

Geographical Range: Alaska to Scammon's Lagoon, Baja California and in Gulf of California.  Most common intertidally in the southern part of the range.  The commonest small intertidal octopus in some areas (especially northern California) but in Washington E. dofleini seems more common.

Depth Range: Intertidal to 200 m.

Habitat: Kelp beds (juveniles often washed ashore in kelp holdfasts), rocky areas, sandy mud bottoms, under stones on low intertidal.

Biology/Natural History: The sixth pair of suckers is enlarged on all but the ventral arm of males.  Male hectocotylus is conspicuous, about 1/10 the length of the 3rd right arm, where it is located (photo).  The ink is reddish or red-brown.  The larvae have a double row of chromatophores on each arm (E. dofleini has only 1 row/arm).  Adults eat crustaceans, mollusks, and fishes.  They especially seem to prefer to eat small crabs and hermit crabs.  Females guard egg clusters intertidally or shallow subtidally from late spring through early winter in rocky areas.  Peaks in breeding are in August and September.  Young hatch in 6-8 weeks, spend a brief period in the plankton, and settle as juveniles in the kelp beds.  Larger individuals migrate farther offshore on sandy mud bottoms.  They mate in deep water in late spring, then move inshore again.  They ae often found in prawn traps.

References:

General References:
  Gotshall, 1994
  Harbo, 1999
  Kozloff, 1993
  Morris et al., 1980
  Niesen, 1994
  Ricketts et al., 1985

Scientific Articles:
Anderson, Roland C. and Eliza A.H. Little, 2006.  Observations of a brooding Octopus rubescens (Cephalopoda: Octopodidae).  The Festivus 38:1 pp 10-12 (San Diego Shell Club)

Mather, J.A. and R.C. Anderson, 1993.  Personalities of octopuses (Octopus rubescens).  J. Comparative Psychology 107:3 pp 336-340

Student Projects:
Thomas, Jeremy and Lyndsi Hersey, 2006.  Remote chemosensory and feeding in Octopus rubescens near Deception Pass, Washington.   Jeremy and Lyndsi tested whether this species would use its chemosensory powers to respond to the smell of prey.  Using two different red individuals, they repeateadly placed either two clear plastic tubes or two opaque plastic tubes into their aquaria, then placed a crab into one of the tubes while out of sight of the octopus.  The water inlet was flowing through the tubes so that the smell of the prey should enter the water.  They observed the octopus' behavior for 20 minutes after placing the prey in the tube.  The showed little special interest in the opaque tubes.  They occasionally contacted the tubes or even climbed on top of them and reached their arms partly inside, but never encountered or captured the prey.  On several occasions the octopus actually entered a tube but it happened to be the empty one.  With the clear tube (through which they could see the prey) the octopus several times quickly swam to the tube and embraced it, but could not seem to figure out that they had to go to the end of the tube to capture the prey.  More often they would ignore the prey, which was standing mostly immobile at the bottom of the tube, even though the prey was clearly visible to them.  As soon as prey were released free into the tank, the octopus quickly captured them.  The students concluded that this species does not seem to use smell to find prey, but need to see the prey moving and/or actually touch the prey in order to be stimulated to capture it.
 
 

I have seen this species swimming at about 500 m depth in Monterey Bay in late spring (observations using the MBARI Ventana ROV).  Presumably these individuals were adults which had swum out to deep water to breed.

This individual is trying to sneak away through the intertidal algae.  Dave Cowles, San Simeon, CA 1997

This individual has about a 20 cm arm spread.  Captured near Rosario.  This individual is a male.  It usually keeps its hectocotylus arm coiled, as can be seen on the
left in this view.  The hectocotylus arm is the third arm on the animal's right side.  The first and second arms on the right are straight and the third arm is coiled in this view.
Photo by Dave Cowles, June 2006

Photo by Dave Cowles, July 2006	Photo by Kirt Onthank, April 2007	Photo by Kirt Onthank, April 2007
It is said that one way to distinguish Octopus rubescens from small Enteroctopus dofleini is that O. rubescens has three distinct cirri below the eye, as seen in these views.

In this photo, the same individual shown in the tank above has eaten an oregon cancer crab Cancer oregonensis which was nestling within the plates of a dead barnacle, then took over the barnacle.  Notice the mottled camouflage appearance and the three cirri clearly visible below the eye.

This photo shows a female Octopus rubescens (right and bottom) tending her eggs (center) which she has laid inside a beer bottle.
The bottle is encrusted with barnacles and tubeworms.  Photo by Kirt Onthank, 2007.

The beak of an Octopus rubescens adult is about 1 cm long.
This is the beak of the brooding female from the picture above, which died after brooding her eggs for 3 months.
Many of the eggs had become cloudy and did not appear viable after the 3 months.
Photo by Kirt Onthank, March 2007
 
 

Here are several more photos of an O. rubescens which has become accustomed to handling, showing some of the different color patterns and textures it can take on within a few minutes. Photos by Kirt Onthank, April 2007 In this closeup view of the arms from a mature male, the tip of a non-hectocotylus arm (right arm #2) can be seen on the left while the hectocotylus arm (right arm #3) is on the right.  The tip of the hectocotylus arm is thicker and not lined with suckers. Photo by Dave Cowles May 2007 This 1-day-old larva, about 2 mm long, was released by a brooding mother in July in our running seawater aquarium. Photo by Dave Cowles, July 2007 An Octopus rubescens tries to blend in with the background.  Underwater photo at Admiralty Bay by Kirt Onthank, July 2007