(Hapalochlaena lunulata)
Don’t mess with the blue blue-ringed octopus! It may be only the size of a golfball, but it contains one of the most deadly neurotoxins in the world, that can kill an adult in a few minutes! Before it strikes, the octopus sends out a warning by flashing its rings a bright blue. But if you wait too long, it bites! Sending its venomous saliva deep into your flesh! But the venom isn’t the only interesting part about the octopus. (Ok, maybe it is.) The octopus shows its bright rings by flexing its muscles. The rings are always there, but pouches of skin conceal the octopi’s neon rings when they are relaxed. The main component of the octopuses’s venom was thought to be something known as malculotoxin, but was later found to be exactly identical to tetrodotoxin, a neurotoxin found in pufferfish that is 10,000 times more toxic than cyanide. Tetrodotoxin causes motor paralysis and respiratory arrest, leading to cardiac arrest. The venom can also cause nausea, heart failure, total paralysis, and blindness. Death is usually from suffocation, due to a lack of oxygen delivered to the brain. But, death is not always certain. A certain toddler playing at Suttons Beach in Australia was rushed to a hospital and managed to survive the bite. In 2006, 4 deaths were recorded, and in all cases, the bite was inflicted after the victim picked up the octopus.
Blue-ringed octopuses don’t usually attack humans, in fact they’re mostly docile: their main prey is small crabs, hermit crabs, and shrimp, although sometimes they’ll feed on fish if they can catch them. The octopus first pounces on the prey, pulling it towards its mouth, so its hard beak can pierce the exoskeleton of the prey, when it then first uses its venom. The venom paralyzes the muscles used for movement and
breathing. The octopus then tears off part of the shell with its beak and sucks the flesh out of the crustacean.
50-100 eggs, and then guards them. She does eat during the entire gestation period, which lasts 1-2 months, then dies. The little juveniles are the size of a pea, and like to hide underneath sandy ledges. The little BRO will grow to be at adult size in only a few months, living altogether only about 2 years. BRO’s have very small ink sacs, and have lost the defensive mechanism of the ink sac, probably due to the fact that because they can use their rings, venom, camouflage, and hiding skills to keep away predators, ink
was no longer needed.
(Enteroctopus dofleini)
The Giant Pacific Octopus weighs up to about 50 lbs. (sometimes much more) and often has a mantle length in excess of 1.5 ft., yet can squeeze through an aperture the size of a lemon. While a solitary and shy animal, the octopus's 5-ft. arms with a combined total of 2000+ powerful, chemical receptor-studded suckers allow it to take on some of the most dangerous predators in the East-Central Pacific. It can survive for at least fifteen minutes out of water, it swims swirling its arms around itself to slough off its victims' dead skin from its suckers, and it makes its home in dark, rocky caves in Pacific waters that can reach 36 degrees Fahrenheit (cold for any cephalopod). It is the ultimate marine invertebrate predator in most all respects. The Shedd Aquarium's website dramatically describes E. dofleini as "like a clan of ancient gods and present-day superheroes rolled into one," with the "suctioning force of Spiderman, the brains of Athena, the stretching capacity of Elastigirl, the speed of Mercury and the determination of Wonder Woman."
E. dofleini will eat just about anything: fish ranging in size from small perciformes to dogfish and other shark species, crustaceans like prawns and lobsters, clams and other bivalves, and birds. Yes, birds. Some females are even cannibalistic. In trophic terms, Giant Pacific Octopuses are secondary or tertiary consumers, high-level small-population predators that feed on herbivorous organisms and smaller predators. The Giant Pacific Octopus is an important prey species for Pacific marine mammals like seals, sea lions, and toothed whales like the Killer and Sperm Whales (Orcinus orca and Physeter macrocephalus). The Octopus's meat is lean, but rich in proteins and a variety of important vitamins and trace metals these mammals need. However, the Giant Pacific Octopus is by no means an easy catch:
In ecological terms, the Giant Pacific Octopus's semelparous (single-cycle, with senescence after one breeding event), relatively short lifespan (4-5 years) and 70,000-egg clutch size is indicative of an rapid-life history reproductive strategy substituting parental investment with bulk. Giants Pacific Octopuses mate in the winter months, with males using a hectocotylized arm to insert two spermatophores into the female oviduct; the whole spawning process takes a few hours. The male immediately experiences programmed senescence and cessation of metabolic activity; the female stays alive to guard the eggs over the next 3-5 months as they incubate in clusters of 200-300, hanging from the roof of the octopus's den. The larvae hatch in spring, and spend 1-3 months in a 10-millimeter planktonic stage, after which they grow rapidly.