Ocean News Unofficial

Well, technically it's not new : it's a nurse shark. What's new, however, is that it's the first xanthic (imagine albinism but in yellow) nurse shark ever found !! Not only it's not common AT ALL to find fishes with xanthism (it's the first cartilagenous fish ever recorded with this type of genetic "anomally"), but if it's there and still existing as an adult, it means the species is chill-ish with other predators (it probably would have been eaten by then). Its eyes are white so it can also be a form of albinism, in addition to xanthism !!!!!

And most of all : ITS SO CUTE !! AND IT'S SUCH A COOL FIND !!

Please if a marine biologist or someone with more info can interact with this post to feed me some more info or correct me on wrong infos i'e given I'd love it !

Scientists have just discovered some rocks at the bottom of the ocean can make oxygen... and they do it in complete darkness!

These aren’t magic stones, they’re polymetallic nodules, potato-sized metal lumps packed with manganese, cobalt, and nickel.

But here’s the twist; when seawater flows over their surfaces, they generate tiny electric currents that can split water molecules into hydrogen and oxygen. No sunlight, no photosynthesis, just deep-sea chemistry creating breathable gas in the pitch black.

Its actually wild to me that's I've been doing this series for almost 2 years and somehow haven't covered a single octopus yet. I've done squid, cuttlefish, nautiluses, and the vampire squid, but somehow the most famous corner of the cephalopod family reunion has eluded me. Time to change that. And why not go big and cover the biggest (maybe) octopus of them all?

(Image: a giant Pacific octopus crawling on the seafloor. It is a large, red, soft-bodied invertebrate with wrinkly skin. A bulbous head contains the eyes and opening to the mantle. Attacked are eight long arms lined with suckers. End ID)

Enteroctopus dofleini is the giant pacific octopus, though genetic studies have indicated that there may be multiple distinct subspecies based on location. They are considered the largest octopus species in the world, though that may not actually be the case. Adults usually reach an arm span of 4.3 meters (14 ft) and weigh up to 15 kg (33 lbs), with some large specimens getting up to 50 kg (110 lbs). That held the record for a long time, but in 2002, a dead specimen of Haliphron atlanticus, the seven-armed octopus was pulled up and while it was incomplete, its size while alive was estimated to be 3.5 m (11 ft) from top to arm tip and 75 kg (165 lbs). Seven-armed octopi are much more elusive than giant Pacific octopi, so we don't have nearly as many specimens to go off of, but if that sample is anything to go by, they are even bigger than the GPO.

(image: divers next to a giant Pacific octopus shown from below with its arms spread, showing off the suckers and the radius of the tentacles, which is larger than the diver. End ID)

The giant Pacific octopus's anatomy is typical of an octopus, just scaled up. It has two body segments: the head and the arms. The head is bulbous and contains the organ systems, including the brain, digestive system, renal system, and all three hearts, and is covered by the mantle. The arms (not tentacles as commonly thought) are eight limbs lined with powerful suckers, each of which can be moved independently. The only hard part of an octopus's body is the beak, used to chop up food. Because the rest of the body is so malleable, an octopus can squeeze its body through any hole large enough to fit the beak. The beak is also venomous, though only a few octopi possess venom potent enough to harm a human and the GPO is not one of them. Octopi (I can rant about what the proper plural is later, but as far as I'm concerned, octopi is perfectly acceptable) along with their squid and cuttlefish relatives, have special pigment-filled cells called chromatophores lining their skin. Using muscular action, the octopus can individually widen or shrink each chromatophore to radically change its color. This is used mostly as camouflage, but can also be used as a threat display in some species (such as the blue-ringed octopus) or for communication. The GPO is usually a ruddy red color when resting. Skin texture can also be altered with muscles, but in the GPO it is usually uneven, with long lateral folds that give it a wrinkly appearance. Octopi have a siphon concealed in the mantle that is used to pass water over the gills and for propulsion.

(Image: a GPO crawling through an aquarium tank. Purple sea urchins and anemones are in the background. End ID)

The giant Pacific octopus live in (surprise, surprise) the Pacific ocean. Specifically in the northern regions from the Yellow Sea in southern China, up through the eastern coast of Russia, across to Alaska, and down as far south as southern California. They are found in reefs and rocky bottoms with plenty of places to hide. The GPO occupies a middle portion of the food web. They are predators who feed on hard-shelled invertebrates, fish, and smaller cephalopods. They hunt prey as large as the spiny dogfish shark, which can grow up to 1.2 m (4 ft) and have been reported to attack and drown seagulls. In turn, they are fed on by sharks and marine mammals. Octopi are especially skilled at eating hard-shelled invertebrates like bivalves, as their powerful arms and suckers allow them to pry open the shells to get at the meat within. Octopi need to bite their food into small chunks as their brains are donut-shaped and circle the esophagus. Swallowing something too big can give them brain damage. The GPO prefers to dwell in dens, but will also hide amongst kelp or camouflaged among rocks. Dens can be spotted by looking for the discarded shells of meals piled up outside them They spend most of the day motionlessly resting (something anyone who has ever been disappointed at the octopus exhibit in the aquarium can tell you) and are most active between midnight and early morning. When active, they hunt and search for new hiding spaces. Large GPOs can travel lond distances in search of habitats and mates. Populations in Asia are known to migrate to shallow water in winter and deeper water in summer. They can remember where they've been by using visual stimuli. When threatened, they can release a cloud of toxic ink to blind attackers while they flee.

(Gif: a GPO crawling along the seafloor, showing off how the arms work together to move it. End ID)

Giant Pacific octopi live for up to five years, which makes them ancient by octopus standards. Most species only live for one year. Like all cephalopods except for nautiluses and possibly the vampire squid, giant Pacific octopi are semelparous, meaning they reproduce only once in their lives. This happens in fall and males will seek out females to mate with. Males have a modified arm called a heterocotylus that they reach into a hole in the female's mantle to deposit a packet of sperm that can be over a meter long. The female can then hold onto the packet to fertilize her eggs up to several months later. Genetic testing indicates that both males and females will mate with multiple partners. The female must find a suitable den and will lay up to 400,000 eggs in clusters attached to a hard surface. For the next 6 months, she will stay with her eggs to protect them, blowing oxygenated water over them and cleaning them of algae and other contaminants. She does not eat during this period, subsisting on her internal fat stores. By the time the eggs hatch, she will either have starved to death or will do so shortly. Males also do not survive past mating season. They also stop eating and become more prone to acting in the open, leaving them more vulnerable to predators. The newborn octopi are called pseudolarvae and are roughly the size of a grain of rice. Once hatched, they enter the water column and live amongst the zooplankton. Only a very few of the peudolarvae will survive to adulthood. The majority will succumb to disease or predation. Sexual maturity is regulated by a gland called the optic gland, which is analogous to the pituitary gland in vertebrates. Experiments have shown that females whose optic glands have been removed stop brooding their eggs and resume hunting. They also resume gaining weight and have longer lifespans.

(Image: a female GPO in her den. clusters of small, white eggs hang from the ceiling. End ID)

(Image: GPO eggs about ready to hatch. They are transparent, oblong capsule with the juveniles visible within. They have similar anatomy to the adults, but with visible ink sacs. End IS)

Octopi are the most intelligent of all invertebrates. They are capable of solving puzzles based on trial and error. Indeed, those living in aquariums are often given puzzles to solve as a form of enrichment. Aquarium workers have reported that giant Pacific octopi can recognize individual people and can hold grudges. Captive octopi are notorious for doing things like disabling mechanisms in their tanks, pranking certain people, and even escaping their tanks to visit other ones, then returning to theirs before anyone comes by to catch them. They are capable of tool use and can use shells and human-made objects to build defensive structures around their dens and some small species use shells or other objects as armor. Brain surface area often correlates to intelligence in areas and octopi have the highest ratio of all invertebrates. They are a rare example of an invertebrate whose brains are wrinkled the way those of tetrapods are. Only about a third of all the neurons within the nervous system are located in the brain. There are also major nerve clusters in each arm. It has been said that the arms have brains of their own, though this is not entirely accurate. The arms are capable of independent action, though learning happens in the brain. The arm brains also work to process the massive amount of sensory data they gather. Even a severed arm can act independently until it starves. There are videos out there of uncooked or undercooked octopus arms moving around on plates or grabbing onto diner's faces.

(Image: a GPO in an aquarium being given food in a jack-o-lantern as a form of enrichment. End ID)

The giant Pacific octopus is classified as least concern by the IUCN, meaning they are not at risk of extinction. They are considered abundant through their range, though they are at higher risk in some locations. GPOs are also harvested for seafood, being popular throughout their range and beyond. The GPO, along with the big blue and common octopi, are the most commonly eaten species in the Pacific. Pollution, climate change, and ocean acidification are also known to be threats to octopi. A threat that doesn't exist anymore is the "sport" of octopus wrestling. This involves divers grabbing octopi and trying to pull them to the surface, with GPOs targeted due to their size. The octopus was an entirely unwilling participant in this, they are very shy animals that prefer to flee rather than fight. Fortunately, this form of recreational animal abuse doesn't really exist anymore.

June 15, 2024

Expressing my lifelong love of sharks by painting a sweet little nurse shark

mackerel

I'm so happy I can finally reveal this guy to you! This mackerel is a part of a collab with the great Mbogdanis, who suggested we could make silly fish bookmarks together :D We sold most of the current stock, but we'll be reprinting them!