Apr 25

Cephalopods are arguably the weirdest of all marine invertebrates. The name cephalopod literally translates to ‘head-footed’ in Greek, indicating just how strange members of this taxonomic class are, but nothing in their name indicates how incredibly intelligent they are. Their alien-like features are truly fascinating and cephalopods are commonly regarded as the most advanced of all invertebrates!

The weirdest one – nautilus (Nautilus pompilius)

Kicking off our list is the bizarre-looking nautilus, whose appearance resembles a cross between a snail and a shrimp. They are the only species of cephalopod to have retained their external shell, which means they cannot alter their appearance as well as their counterparts.

The invisible one – common cuttlefish (Sepia officinalis)

The common cuttlefish is a master of disguise, possessing the ability to transform its appearance to suit its surroundings in an instant. Check out this amazing talent in this video!

The deadly one – southern blue-ringed octopus (Hapalochlaena maculosa)

This species has one of the most potent venoms on the planet, 1000 times more powerful than cyanide, and there is no known antidote. The blue rings after which this species is named will only appear when an individual is disturbed and serve as a warning before it attacks. The helpless crab in this video finds this out the hard way!

The strangely familiar one – opalescent squid (Loligo opalescens)

You may have come into contact with this cephalopod more than any other – the opalescent squid is more commonly known to us as ‘calamari’. These small squids live in extremely large shoals and hunt by striking their prey with their tentacles.

The one-size-fits-all one – curled octopus (Eledone cirrhosa)

The ability of the curled octopus to transform and camouflage its body is truly fascinating – there is no gap too small or seaweed too colourful for this species! The curled octopus is also equipped with an ink jet they can utilise as a distraction when a predator is nearby. On top of all that, it also has an extremely toxic venom that it uses to paralyse its prey!

The colourful one – Carribean reef squid (Sepioteuthis sepioidea)

Commonly found in shallow reef waters, this intriguing species has enormous eyes and is known to have the largest eye-to-body ratio of the whole animal kingdom! Carribean reef squid communicate with each other by changing the colour of their skin.

The huge one – giant Australian cuttlefish (Sepia apama)

The giant Australian cuttlefish is largest cuttlefish species, reaching lengths of up to a metre.  Despite its large size, this species it is a master of disguise and can easily blend in with its  surroundings due to special pigment cells called chromatophores which allow it to change colour in an instant.

The even huger one – Humboldt squid (Dosidicus gigas)

A close relative of the giant squid, this species, also known as the ‘jumbo squid’, is a monster capable of growing up to 2 metres long and weighing over 50 kilograms! They can move at considerable speeds (up to 24km/h) and have been known to propel themselves out of the water and soar through the air to evade their predators which include whales, sharks, seals and swordfish.

The bright one – firefly squid (Watasenia scintillans)

This bioluminescent species is definitely deserving of a top 10 spot as it is responsible for one of the most spectacular light shows on the planet! Between March and June millions of firefly squid gather off of the coast of Japan, as well as hundreds of tourists, producing a natural spectacle like no other. The firefly squid also uses its bioluminescence to attract prey and select mates.

The strong one – North Pacific giant octopus (Enteroctopus dofleini)

Reaching lengths of up to 5 metres and weighing in at up to 50 kilograms, this monster octopus had to make the top 10! The photograph below is not photoshopped, this species does eat sharks! Its raw strength makes it capable of ripping apart shells and flesh with its tentacles or using its powerful ‘beak’ to make easy work of its prey. This, in tandem with its camouflaging talent, makes it a truly ferocious predator.

Have we missed out your favourite cephalopod? Let us know!

Discover more cephalopods on the Arkive website

Will Powell, Arkive guest blogger

Feb 1

We’ve asked conservation organisations around the world to nominate a species that they believe to be overlooked, underappreciated and unloved, and tell us why they think that they deserve a fair share of the limelight, this Valentine’s Day.

Each nominee’s story is featured on the Arkive blog with information on the species, what makes them so special, the conservation organisation that nominated them and how they are working to save them from extinction.

Click the ‘unloved species’ tag above to see all of the nominations and their blogs.

Once you have perused the blogs you can vote for your favourite to help get them into the top ten unloved species and get them the recognition that they truly deserve! Share your favourite with others using the #LoveSpecies hashtag on Twitter and Facebook and tell them why they should vote for them too. Voting closes on February 14th at 23:59 PST (07:59 GMT).

Join us and our conservation partners in celebrating and raising awareness for some of the world’s most unloved species this Valentine’s Day!

Species: Common octopus

Nominated by: Sea-Change Project

Conservation status: There is the potential for the overfishing of these animals, which threatens their proliferation. They are not at specific risk, but removal of large quantities has effected many important predators that rely on octopus for food.

Why do you love it? Octopus vulgaris only live for about 12 to 15 months depending on water temperature. Its super intelligence is partly instinctive, partly learned. They can make judgements based on visual, tactile, and chemical cues and their ability to conceal themselves on any substrate by changing colour, skin, texture, posture and brightness is challenged by few other animal species.

What are the threats to the common octopus? Octopus vulgaris is one of the most common octopus species commercially fished for food and for the aquarium trade.

What are you doing to save it? Over a period of four years diving almost daily, filmmaker and citizen scientist Craig Foster has watched these animals in three different ways, firstly by hiding behind kelp and watching them, setting up remote cameras (often outside their dens) and watching the footage afterwards and presenting himself as a predator in the forest, before taking photographs of their defensive response. Most of the octopuses he encountered seemed afraid and generally camouflaged themselves. When they realised they had been seen, they tried to threaten him by jetting water at him or displaying threat postures, then walking or swimming away, occasionally squirting ink if Craig got too close. A few individuals have behaved in quite the opposite manner, instead of fleeing they approached Craig and grabbed onto his hand with all their tentacles.

Even when he had to swim to the surface to get air they kept holding on and rode on his hand to the surface, eventually letting go. Craig has never been bitten or felt threatened. Vulgaris are too small to pose a threat to humans, but their bite is venomous.

In the past two years Craig has observed some unusual behaviour which to the best of our knowledge has not been documented before.

Find out more about the Sea-Change Project

Discover more Cephalopod species on Arkive

 

VOTE NOW!

 

May 28

Arkive’s Week in Review — Wildlife News

ICYMI: Arkive has compiled some of the biggest and most interesting headlines from this week.

Article originally published on Friday, May 22, 2015

Octopus has the ability to see with its skin

Common-octopus

Common octopus

In a recent study, researchers found that octopus skin contains the same light-sensitive proteins found in eyes. The skin responds to light independently of the central nervous system, and detects changes or increases in light brightness.

View original article

Article originally published on Saturday, May 23, 2015

Rescue workers try to save oil-soaked pelicans

Brown-pelican-on-water

Brown pelican on water

Rescuers have been able to rescue eight brown pelicans, but an intensive clean-up process awaits them. Pelicans must acclimate to their new surroundings for 48 hours and are afterwards extensively cleaned. They are then taken care of for two weeks after which they can return to the wild.

View original article

Article originally published on Sunday, May 24, 2015

Synthetic horns may offer hope to endangered rhinos

Black-rhinoceros-anterior-view

Black rhinoceros

Currently, three of the five rhino species are critically endangered primarily due to poaching for their horns. A California biotech start-up, however has posed an unorthodox solution; creating synthetic rhino horns to offer consumers an ethical alternative. Conservationists are skeptical that synthetic horns will reduce demand for the real thing.

View original article

Article originally published on Monday, May 25, 2015

Endangered saiga antelope mysteriously dying in vast numbers in Kazakhstan

Male-saiga-antelope-walking

Male saiga antelope

Around one-third of the saiga antelope population in Kazakhstan has mysteriously died. Their agriculture ministry hypothesizes that a pasteurellosis epidemic might be the culprit. As of yet the cause has not been officially determined.

View original article

Article originally published on Tuesday, May 26, 2015

Mozambique loses almost 10,000 elephants in just five years

African-elephant-family

African elephant family

In 2010, Mozambique was home to approximately 20,000 elephants, but today it houses only 10,300. Almost all of the poaching occurred in the remote northern region of the country. Celso Correia, Mozambique’s new Minister of Land, Environment and Rural Development, has stated that tackling poaching is a top priority of the government.

View original article

Article originally published on Wednesday, May 27, 2015

World’s rarest porpoise is dying to feed a black market in fish bladders

Vaquita-calf-at-the-surface

Vaquita calf at the surface

In a recent report, Greenpeace officials noted that vaquitas are being caught and drowned in illegal gillnets, which are meant to catch totoabas, another endangered species. The vaquita population was 200 in 2012, but now only 97 individuals remain.

View original article

Article originally published on Thursday, May 28, 2015

An erupting volcano threatens one of the world’s rarest animals

galápagos-pink-land-iguana

Galápagos pink land iguana

Isabela Island, where a volcano is currently erupting, is the sole home of the Galápagos pink land iguana. Park officials are monitoring lava flows, which thus far have not affected the 200 iguanas on the island.

View original article

Enjoy your weekend!

William Lazaro, Arkive Social Media Intern, Wildscreen USA

 

 

 

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