The California two-spot octopus is usually light brown or mottled in coloration, with two characteristic spots under each eye, hence its name. Its mantle, located in the center of eight tentacles, is pear-shaped with a beak and mouth in the middle. Each of its tentacles grow to a few feet in length, a little more than half of its body size. Its tentacles are each adorned with suction cups used for grasping and holding prey as well as for taste. The octopus can grow to about 18 inches long when fully mature. Like its relatives, Octopus bimaculoides is another species of octopus that has the same common name as because they look so similar, but it is important to know that they are two different species. ("Two-Spotted Octopus", 2013; Foster and Smith, 2013; L. D. Roberts, 2009; Semmens, et al., 2004)can use the chromatophores in its skin to change its color and texture when hunting for prey or hiding from predators.
After fertilization, the female will create a den and seal herself in to lay her eggs. A single female can lay thousands of eggs. She will care for her eggs by blowing cool water over them from her siphon to keep them oxygenated. During the process of caring for her eggs, the female often expires due to starvation and exhaustion. After the eggs hatch, which may take 150 to 210 days, the mother will leave the den if she survives and the larval octopus will drift with the tide before settling on the ground to begin developing. ("How Does An Octopus Reproduce?", 2003; Boal, 2006)
Males die shortly after mating. Females, however, exhibit significant parental care. They remain with the eggs after they are laid, protecting them and siphoning cool water over them. During this time, females do not feed and often die from starvation and exhaustion. Once the eggs hatch, the larvae are independent. ("How Does An Octopus Reproduce?", 2003)
Predators of (Kier and Smith, 2002)include moray eels, sea lions, harbor seals, and humans. To scare off predators, can change its skin by manipulating its chromatophores and flashing warning signals.
California two-spot octopuses are both primary and secondary consumers. They help maintain the population of smaller mollusks as well as serve as food for larger predatory animals. They are also known to be hosts for ectoparasitic flagellates and ciliate protozoans, which live on the octopuses' gills. (Forsythe, et al., 1991)
This species of octopus is not hunted by humans as a main source of food, however it is caught in traps and nets and can be sold. As of 2013 in California, the daily bag limit is 35 specimens, and there are no size limits. There is a market in the pet supply trade. Because two spotted octopuses are small (up to 45 cm), they are welcome aquarium pets. Aquarium websites list them from US $30 to $40 depending on size. ("Listings and Occurences for Endangered Species in California", 2013; Foster and Smith, 2013)
There are no known adverse effects ofon humans.
Brittany Hamilton (author), San Diego Mesa College, Lauren Swope (author), San Diego Mesa College, Paul Detwiler (editor), San Diego Mesa College, Angela Miner (editor), Animal Diversity Web Staff.
body of water between the southern ocean (above 60 degrees south latitude), Australia, Asia, and the western hemisphere. This is the world's largest ocean, covering about 28% of the world's surface.
uses sound to communicate
Referring to an animal that lives on or near the bottom of a body of water. Also an aquatic biome consisting of the ocean bottom below the pelagic and coastal zones. Bottom habitats in the very deepest oceans (below 9000 m) are sometimes referred to as the abyssal zone. see also oceanic vent.
having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.
an animal that mainly eats meat
uses smells or other chemicals to communicate
the nearshore aquatic habitats near a coast, or shoreline.
having markings, coloration, shapes, or other features that cause an animal to be camouflaged in its natural environment; being difficult to see or otherwise detect.
animals which must use heat acquired from the environment and behavioral adaptations to regulate body temperature
parental care is carried out by females
union of egg and spermatozoan
A substance that provides both nutrients and energy to a living thing.
having a body temperature that fluctuates with that of the immediate environment; having no mechanism or a poorly developed mechanism for regulating internal body temperature.
Animals with indeterminate growth continue to grow throughout their lives.
fertilization takes place within the female's body
the area of shoreline influenced mainly by the tides, between the highest and lowest reaches of the tide. An aquatic habitat.
imitates a communication signal or appearance of another kind of organism
eats mollusks, members of Phylum Mollusca
Having one mate at a time.
having the capacity to move from one place to another.
specialized for swimming
the area in which the animal is naturally found, the region in which it is endemic.
active during the night
reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.
the business of buying and selling animals for people to keep in their homes as pets.
structure produced by the calcium carbonate skeletons of coral polyps (Class Anthozoa). Coral reefs are found in warm, shallow oceans with low nutrient availability. They form the basis for rich communities of other invertebrates, plants, fish, and protists. The polyps live only on the reef surface. Because they depend on symbiotic photosynthetic algae, zooxanthellae, they cannot live where light does not penetrate.
mainly lives in oceans, seas, or other bodies of salt water.
remains in the same area
offspring are all produced in a single group (litter, clutch, etc.), after which the parent usually dies. Semelparous organisms often only live through a single season/year (or other periodic change in conditions) but may live for many seasons. In both cases reproduction occurs as a single investment of energy in offspring, with no future chance for investment in reproduction.
reproduction that includes combining the genetic contribution of two individuals, a male and a female
uses touch to communicate
that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).
defends an area within the home range, occupied by a single animals or group of animals of the same species and held through overt defense, display, or advertisement
movements of a hard surface that are produced by animals as signals to others
uses sight to communicate
breeding takes place throughout the year
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