Catalina Island Marine Institute
This 18-foot-long (5.5 meters) oarfish was found off a beach in Southern California on Oct. 13, 2013, and is held here by staff from the Catalina Island Marine Institute. A recent dissection of the creature found it was teeming with parasites.
What has eight arms with hundreds of suckers, eyes the size of grapefruit and a razor-sharp beak? A giant squid! A team of scientists and the Discovery Channel shot footage of this notoriously elusive creature in action. Click ahead for more squidly fun.
Giant squid have captured, and terrified, the seafaring imagination for centuries. This illustration recreates a giant squid observed off Tenerife in November of 1861.
This giant squid was collected by NOAA researchers off the Louisiana coast in the Gulf of Mexico. The largest invertebrate on Earth, the giant squid is just plain big -- the largest ever found was 59 feet (18 meters) long.
The only squid bigger than a giant is the colossal squid. Captain John Bennett examines the world's first intact adult male colossal squid in 2007 in the Ross Sea, near Antarctica. The squid was about 33 feet (10 meters) long. Check out those suckers!
These two female giant squid were found off Luarca, Spain. For an idea of the size of these creatures, note the gloved hand in the upper-left.
Alien autopsy? Nope. It's one of the Luarca squid from the previous slide, undergoing an examination by Spanish scientists.
Here's a giant squid measuring about 28 feet (9 meters), on display at London's Natural History Museum. This creature was caught in March of 2004, at a depth of 722 feet (220 meters), off the Falkland Islands in the South Atlantic.
A cat strolls past a giant squid in January 2005 in Newport Beach, Calif. That winter hundreds of 3- to 4-foot-long (0.9 to 1.2 meter) squid washed up along the Southern California coast. One theory holds that they ran ashore while chasing grunion.
This is another shot of a squid from the Newport Beach, Calif. wash-up. Giant squid eyes look so human because they’re structured much like human eyes are.
It may look big in the photo, but this larval squid is just 0.4 inches (1 centimeter) long and was photographed through a microscope by Russ Hopcroft, of the University of Alaska Fairbanks.
The humboldt, or jumbo, squid is a carnivorous marine invertebrate with a lifespan of only 1-2 years. But it makes hay while the sun shines on its short life: In that time, it can grow to 4 feet (1.2 meters) long.
We may know it better as calamari, the familiar appetizer, but its proper name is common market squid. This adult market squid was photographed off La Jolla Shores Beach in La Jolla, Calif.
This adult jumbo squid was caught near the Channel Islands by a squid jig aboard an NOAA research ship in 2007. Its tentacles are wrapped around the jig that was used to catch it, which worked by attracting the squid to its glowing yellow plastic.
This is a closer look at the 2007 Channel Islands squid. Its telltale large eyes allow the creature to see in the very low light that permeates its deep underwater habitat.
A squid's razor-sharp beak is a merciless weapon against its prey, allowing it to chomp tasty bites out of its victims. Here we see a close-up of a Caribbean reef squid's beak.
Researchers have dissected the two deep-sea oarfish that washed ashore in southern California this month. So far, they found that one was teeming with worms and the other was about to have babies.
On Oct. 13, an 18-foot-long (5.5 meters) oarfish was dragged to shore by a snorkeler at Catalina Island. Because the species lives in deep, dark waters, up to 3,000 feet (915 meters) below the surface, intact specimens are rarely discovered. Strangely enough, another smaller oarfish washed ashore north of San Diego just a few days later.
Parasitologists from the University of California, Santa Barbara jumped on the once-in-a-lifetime opportunity to study the elusive creature and asked for a small tissue sample of the oarfish that washed up at Catalina Island. When the researchers cut through a tiny portion of the fish's intestine last week, they found it was carrying a heavy parasite load. [Photos of the Largest Fish on Earth]
"Our findings say that these are actually majorly parasitized fish," Armand Kuris, a professor of zoology at UC Santa Barbara, said in a statement. "In this little piece of intestine that we had, we found quite a few of these rather large larval tapeworms. One of them was about 15 centimeters (6 inches) long."
Kuris and colleagues say they also found other parasites that provide insight about the diet of the serpentlike fish. Embedded in the intestine was the hooked proboscis of an adult spiny-headed worm. Parasites hop from host to host throughout their life cycle, so the fact that this worm was mature suggests the oarfish ate its former host, likely krill or some deep-water crustacean, the researchers said.
The second oarfish, which measured 14 feet (4 m) long, is also under scientific scrutiny. Last week, researchers the Scripps Institution of Oceanography reported that they found hundreds of thousands of eggs inside the beast's 6-foot-long (1.8 m) ovaries, according to the Associated Press.
While the causes of death for both of the oarfish remain mysteries, researchers have some working hypotheses.
This 18-foot-long (5.5 meters) oarfish was found off a beach in Southern California on Oct. 13, 2013, and is held here by staff from the Catalina Island Marine Institute. A recent dissection of the creature found it was teeming with parasites.Catalina Island Marine Institute
Scientists with the U.S. National Oceanic and Atmospheric Administration's Southwest Fisheries Science Center performed a necropsy (an animal version of an autopsy) on the smaller oarfish that washed up north of San Diego. Russ Vetter, a NOAA biologist, said in a podcast from the agency that the fish was quite fresh and seems to have stranded shortly before it died.
Vetter suspects the creatures may have been carried closer to shore by a strong ocean current, which the oarfish, being poor swimmers, could not escape. Though they resemble the fearsome sea serpents of folklore, a recent video of a live oarfish in the Gulf of Mexico revealed that the fish are actually quite motionless in their natural habitat; they use paddlelike fins that help them balance as their snakelike bodies hover vertically in the water.
Growing more than 30 feet (9 m) long, oarfish are the world's longest bony fish, a group that includes almost all fish except sharks and rays. (Whale sharks are the largest of all fish.) Further examination of the preserved tissue samples of the beached fish could help scientists uncover more secrets about the species.
"With careful chemical analysis of the lipids and the proteins, we should be able to tell what its diet is and where it fits in the food chain," Vetter said in the podcast, adding that DNA will allow scientists to examine how the oarfish evolved and how the fish is related to other species.
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