The giant Pacific octopus (Enteroctopus dofleini), or GPO, is the largest and one of the most remarkable octopus species in the world. Known for their colossal size, some specimens can reach nearly 10 metres in length and weigh over 270 kilograms, yet they remain masters of stealth and camouflage. These highly intelligent cephalopods possess extraordinary problem-solving abilities and nine brains, allowing them to multitask with incredible precision. Found across the Pacific Ocean, from Japan and Korea to Canada, the USA, and Mexico, they inhabit both shallow waters and deep-sea environments. Beyond their physical prowess, GPOs are devoted mothers, guarding tens of thousands of eggs until they hatch. This combination of intelligence, adaptability, and unique behaviour makes the giant Pacific octopus one of the ocean’s most fascinating and mysterious creatures.
Hunting masters of the night: What giant Pacific octopuses eat
Giant Pacific octopuses are opportunistic predators with a varied diet, including fish, crabs, lobsters, clams, shrimp, scallops, and even other octopuses. Occasionally, they have been observed eating small sharks. They rely on stealth, hunting mostly at night, and use jet propulsion for sudden bursts of speed. Their suckers hold prey firmly while venomous saliva paralyses it. Leftover shells form “middens”, clues that alert divers to their hidden dens.These octopuses live across the Pacific Ocean, from shallow coastal waters to depths of 1,500 metres, spanning regions from Japan and Korea to Canada, the USA, and Mexico. Reproduction is remarkable: males use a specialised arm called a hectocotylus to deliver sperm to females, who store it until ready. Towards the end of her life, a female lays tens or even hundreds of thousands of eggs and guards them for about six months without eating, dedicating herself entirely to their protection until they hatch.
Ocean geniuses: How giant Pacific octopuses show intelligence
Giant Pacific octopuses are among the most intelligent invertebrates, equipped with a total of nine brains: one central brain in their head and one smaller brain in each of their eight arms. This extraordinary neural setup allows them to perform multiple tasks at once, such as opening jars, solving complex mazes, manipulating objects with precision, and squeezing through remarkably tight spaces. Their intelligence extends to social recognition, as they can identify individual humans, and they have even been observed stealing fish from unsuspecting fishermen. According to a study published in Frontiers, cephalopods have different brain types across species. These “cerebrotypes” help them adapt to their behaviour, habitat, and way of life, not just evolution.In captivity, providing enrichment activities such as puzzle boxes or hidden treats is essential to keep them mentally stimulated, showcasing their advanced problem-solving abilities and adaptability in varied environments.
Venomous but mostly harmless: How giant Pacific octopuses interact with humans
While their size may inspire myths like the Kraken, giant Pacific octopuses are not considered dangerous to humans. They do possess venom, but it is mild compared to species like the blue-ringed octopus. GPOs are usually non-aggressive unless provoked, and bites are rarely fatal if treated promptly. Observing them safely in their natural habitat offers a rare glimpse into the life of these intelligent and gentle giants.Although currently classified as Least Concern by the IUCN, giant Pacific octopuses face threats from overfishing, pollution, and habitat loss. They are often caught accidentally as bycatch in crab and cod fisheries. Quick release improves their survival chances, but protecting ocean habitats and encouraging responsible fishing practices remain essential for safeguarding these intelligent and awe-inspiring marine animals for generations to come.Also Read: Malabar gliding frog: The treetop frog that builds a foam nest instead of laying eggs in water