Cephalopods

True Facts About the Cuttlefish 

True Facts About the Octopus

Habitat

Octopus-

•          Usually live in rocks, coral, or burrows.
•          Because they’re invertebrates, they are able to squeeze through narrow passages to find homes.
•          Homes provide protection and they allow the females to lay their eggs.

Squid-

•          Live in warm tropic waters while some live in colder waters.
•          They are found near the sea floor, which is about 10,000 feet below sea level.
•          They are generally found in four oceans.
•          They don’t migrate for new homes.

Mollusks-

•          Some are found on shallow coastal areas while others are In deep ocean.
•          Usually are found where volcanic sediments come in contact with cold waters.
•          They bury themselves in sand, silt, mud, and gravel.
•          They are substrates to help support their heavy shells.

Cuttlefish-

•          Usually found near the Mediterranean, Baltic, and North Sea coasts.
•          They live in temperate waters where the cuttlefish are most comfortable.
•          Use their camouflage to blend in with their habitat to hide from predators and hunt prey.

Feeding

Octopus:

• Crabs
• Whelks
• Small fish
• Mollusks
• Clams
• Lobsters
• Sea Worms
• Shrimp
• Pacific Giant Octopus sometimes go after sharks

Squid:

• Hoki (Grenadier fish)
• Shrimp
• Young sharks and whales (giant and colossal squid)

Cuttlefish:

• Clown fish
• Trigger fish
• Gobies
• Blennies
• Wrasse
• Cardinal fish
• Seahorses
• Damsels
• Tangs
• Crabs
• Shrimp

Nautilus:

• Small fish
• Crabs
• Crustaceans
• Carrion

Types

Octopi:

• Found in every ocean, and there are over 100 species.
• They lack feeding tentacles; most lack fins.
• They seize their prey, inject it with paralyzing toxins, then eat it.
• A female octopus attaches her eggs to rocks and guards them until they hatch; then she dies.

Squid:

• Squids have eight arms, usually two feeding tentacles (longer than arms), and a fin on each side of their mantle.
• They are found in every ocean and are either swimming, floating, or resting on the bottom of the ocean floor.
• Squids that live in shallow waters are active hunters.
• They propel themselves using their siphons and swim/turn using their fins.

Nautiluses

• The only cephalopod with an outer shell (today).
• They are nocturnal.
• Can live for about 20 years.

Cuttlefishes:

• More than 100 species.
• Eight arms and two long, lightning fast feeding tentacles.
• Named after the chalky internal shell they possess and use for floating.

Migration

•Octopus- they migrate from shallow deep waters and back again.

•Squid- they migrate from the north to the south for food and climate change.

•Cuttlefish- the cuttlefish migrate between May and August between False Bay and Fitzegard Bay for food.

•Nautilus-Ultrasonic telemetry techniques were employed to track eleven specimens of Nautilus pompilius for variable times ranging from one to 78 days at Osprey Reef, Coral Sea, Australia.

Anatomy

Organs:

•          High brain-to-body mass ratio; most intelligent of the invertebrates.
•          Three hearts.
•          Gills and Siphon for breathing and jet-propulsion respectively.
•          Gonads typically at the top of the mantle (head).
•          Most have ink sacs.
•          Have bird-like beaks, and most have radulas (multiple rows of up to nine teeth).
•          Large, highly developed eyes, yet they are colorblind. 

Appendages:

• Most have at least eight arms and two or more tentacles
•  Arms are lined with suction cups and tentacles usually have the suckers only at the tips
• “Cephalopod” means “head-foot.”

Size and Color:

•          As big as 60 feet (Giant Squid) to as little as half an inch (Pygmy Squid).
•          Most have chromatophores which stretch and squash to change color.

Nautiluses:

•          Still retain exterior shells.
•          Have about 90 arms that lack suckers but are rather sticky.