THE STEINHART AQUARIUM - Gulf of Guinea Science ...

on temperature.) Females do not feed during
this time, and die after the eggs hatch. (The
male returns to the sea after mating and dies.)
The young are about the size of a grain of
rice, and spend 4–12 weeks drifting in the
plankton, before settling to the bottom for
further development. A giant octopus becomes
sexually mature in about three years.
Mortality/Longevity: Predators include
marine mammals (harbor seals, sea otters, and
sperm whales). Also, occasionally are eaten
by others of their own kind and are caught
commercially. Life span in the wild is 3-5 years.
Conservation Status: Not endangered.
However, the octopus is sensitive to water
pollution and its populations in some areas
may depend on limiting contaminants.
Remarks: The animals are surprisingly
intelligent invertebrates. They are able to learn
and to perform complex tasks, such as twisting
the cap off a jar to reach enclosed food. Captive
animals have been known to leave their tank at
night to feed in other, nearby tanks, and then
return to their home tank before morning.
They are notable for their complex eyes, similar
in structure and acuity to the human eye.
The octopus can change color in less than a
second. In the skin, specialized cells called
chromatophores hold yellow, red, orange,
blue or black pigments. When the tiny muscles
around the pigment cells contract, the colors
show as large spots; when they relax, the colors
dissipate. The octopus uses color change as
camouflage, but also changes color with shifts
in interest and activity, such as during feeding.
When pursued or threatened, the octopus can
squirt ink into the water before fleeing, an
action that confuses and obscures the vision of
predators, helping the animal to escape.
This species is the largest octopus known: the
record forweight is 70 kg (153 lbs) and 7 m (23
ft) arm span.
Red Octopus
Octopus rubescens (Octopodidae)
Distribution: Alaska to Baja California.
Habitat: From the intertidal and shallow
subtidal as juveniles to 180 m depth as adults.
Appearance: Often red, as its common name
implies; however, able to change colors—in the
blink of an eye.
California Academy of Sciences
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Diet: Small crabs (a favorite), hermit crabs, and
other crustaceans, mollusks, and an occasional
fish. Nocturnal forager.
Reproduction and Development: Mate
offshore at depth, then females spawn in the
shallow subtidal. Larvae hatch after 6–8 weeks
of protection and grooming by the female,
who then dies. Juveniles usually live within
the protection of kelp holdfasts before moving
offshore onto the continental shelf, where they
are quite common.
Mortality/Longevity: Life span: about 2 years.
Remarks: See description of giant Pacific
octopus for added information about octopuses
in general.
Female red octopuses in the Discovery Tide
pool may on occasion spawn and be seen
grooming and aerating their eggs.
These animals should not be touched! Not only
do they have sharp beaks and the inclination
to use them, they also secrete venom from
salivary glands on the wound, which can take
several weeks to heal.
PHYLUM ARTHROPODA
CLASS CHELICERATA
ORDER SCORPIONES
Death Stalker Scorpion
Leiurus quinquestriatus (Buthidae)
Distribution: North Africa and the Middle
East.
Habitat: Dry habitats, especially desert areas
except on sand dunes. Hides under stones or
in small, natural burrows and crevices.
Appearance: About 8 cm long; tan body with
slim, small pincers, used for capturing and
manipulating prey, and segmented tail with
stinger, used for delivering venom. Pincers
and stinger tip often dark, even black. Females
larger than males.
Diet: Spiders, insects including crickets, flies,
moths. Occasionally captured by pincers alone,
but usually by venom delivery.
Reproduction and Development: Ovoviviparous;
female bears eggs internally for up to a
year, about 30 young are born live.