Changing Planet

Ghost, Demon, and Cat Sharks Found

Editor’s note: Some commenters have been asking why scientists killed these sharks for their study. To clarify, the sharks were caught as bycatch during commercial fishing operations. The researchers got them afterwards.

You never know what you’ll find when you go rooting around in the dark—especially the deep, dark, remote portions of the sea.

Shark biologist Paul Clerkin conducted a survey in the southern Indian Ocean in 2012 that yielded rarely seen deep-sea sharks, including a possible eight new species. (See more photos of deep-sea creatures.)

Among the exotic finds were elusive 10-foot-long (3-meter-long) false catsharks (Pseudotriakis microdon), a new species of ghost shark sporting what look like buck teeth, and a new species of filetail catshark.

The filetail catsharks were especially memorable for Clerkin, a graduate student at the Moss Landing Marine Laboratory in central California. “They are by far the most adorable shark ever created,” he said.

The catsharks are one foot (0.3 meters) long when fully grown, and have soft, chubby stomachs. “They’d be rolling back and forth on their fat bellies [on the ship], which is really cute, but hard when you’re trying to take a picture of them,” Clerkin said.

For his survey, Clerkin joined a commercial fishing boat trawling the waters above seamounts—or undersea mountains—for fish like orange roughy. He collected samples of sharks caught as bycatch in the ship’s nets, which the fishermen lowered to about 6,600 feet (2,000 meters). “We got a lot of weird stuff,” said Clerkin. (Watch video of a ‘prehistoric’ shark attacking deep bait.)

The remote location contributed to the high number of unknown or rarely seen sharks fishermen pulled up. It took about five or six days to reach the fishing grounds from a port on the island of Mauritius (map), east of Madagascar.

“[This] area is one of the final frontiers for sharks,” Clerkin noted. Fishermen have operated in this part of the southern Indian Ocean for years, he said. “But this is the first time someone’s gone out there to document [the sharks].”

Shark biologist Paul Clerkin confers with colleagues at the Albion Fisheries Research Center on Mauritius about a shark he brought back from his survey.

Clerkin collected a few representatives of each shark species he encountered while recording data like length, gender, and sexual maturity. Clerkin’s work is part of a larger project called Assembling the Tree of Life, which is sponsored by the U.S. National Science Foundation and aims to figure out the evolutionary origins of every living thing.

“I took back a ton of sharks,” he said. The shark biologist ended up mailing about 1.3 tons of samples to laboratories and specialists in the U.S. via air freight.

Clerkin plans on naming at least one of the new species after his graduate adviser and a second one after his mother. “[Maybe] save it for a Mother’s Day gift or something,” he said. (Related: “From Darth Vader to Jelly Doughnuts, Weird Species Names Abound.”)

Jane J. Lee is a news writer and editor at National Geographic.
  • Eric Paul

    It’s nice to be able to discover new species in order to appreciate and protect bio-diversity, but bringing them up from the depths of the ocean to suffer inevitable death doesn’t seem like cause for celebration. If I got anything out of this article, it’s that commercial fishing is a very destructive and unsustainable practice!

  • Christina

    Just wondering why they were killed (if they were) to study them. I mean isn’t it possible that those were the last of its kind? I understand that research is important, but isn’t there some way to study these animals without killing them?

    • Jane J. Lee

      These sharks were brought up as bycatch during a regular fishing operation, so many were already dead. The researcher was able to step in to collect and document these sharks before they were lost to science.

  • Diane

    Jane, thank you for the article about Paul’s research, and for clarifying that the sharks were brought in as bycatch–that Paul collected only those sharks that were already deceased as a consequence of commonly used fishing practices. More about Paul’s work last summer:

  • Kaydie Marie

    Commercial fishing has always been a destructive practice. Fish nets have killed whales, sharks, and dolphins as well as other fish they didn’t want to catch. However, it’s not going anywhere..

  • Amir Samal

    To Eric Paul and all: It is well said that man should farm (in a sustainable manner) and should never hunt. So any form of hunting in the sea may be banned.

  • Tim Bowley

    It was great to learn of these sharks. It is good to know that they were not caught just for research. Granddaughters will enjoy seeing the pics.

  • Far Risk

    Can i work with National Geographic? =)

  • Kathrine

    But the researcher specifically go to these oceans for surveying/researching purposes with intent of actually catching these new species and, eventually, suffering a death. I don’t know. Just doesn’t seem right.

  • Liz

    Aww, I wish that albino ghost shark was not lost. Awesome research!

  • Michael B.

    Dont even bother explaining . . . some people just simply dont know how to read these days, so you will get more ignorants complaining about the research being done with dead sharks. . .as if they were killed for that puropose when you have already clarified they were DEAD already.

  • alex

    Fishing below 300m should be banned.
    It’s totally irresponsible to alow commercial destruction of what we don’t even know. Of corse it’ll never happen because money trumps everything except more money.

  • Elizabeth H

    You’ve got that right, Eric. It’s all about profit without much thought for the way the environment is affected nowadays. Here in Namibia we have the disgusting practice of dredging or bottom trawling where a net is simply dragged across the ocean floor, destroying everything in its path.

  • George

    oh man what does the abyss hide….

    …it’s frightening. Just imagine yourself abyss-walking among these things in total darkness.

    Super nice findings!

  • Ilker van den Berg

    I agree with Eric Paul, bringing these species to the surface and lettings them die is not a really good way of researching them.

    Why has nobody built a research center on the bottom of the sea?

    The Demon shark species looks amazing, beautiful specimen.

    • Jane J. Lee

      In terms of a research center on the bottom of the sea, I suspect the main reason is lack of funding. The U.S. National Oceanic and Atmospheric Administration (NOAA) had an underwater research station off the coast of Florida called Aquarius, but they recently had to let it go because of budget issues.

  • Martin Belk

    Why all these made for TV names? ‘Ghost’ ‘Demon’ etc.? I get the connection, sort of, but it sounds like ‘SHARK WEEK’ BS to me…

    • Jane J. Lee

      Ghost, demon, and cat sharks are the common names for these species. I’m not sure how they came about, but it’s what these groups are called.

  • Ostilio Bonacini

    I agree with M. Paul’s comments: commercial fishing to such depths seems scary. Until when are we humans going to sweep indiscriminately all the world’s oceans? As a leisure and respectful scuba diver I feel both sad and enraged!

  • Greg Konstantarou

    Ok learning about the sharks is interesting, but they need to be dead? Who gives you the rights to determine life and death for creatures though? Those sharks have just as much right to live as you or I.

  • James Oliver

    The extreme pressures which they live must be why they die so quickly as they rise.

  • Mike

    This is either a poorly written article or Nat’l Geo’c is celebrating these sharks demise. Either way it’s not clear that the sharks were not killed for scientific purposes. After reading this my thoughts were 35!?, why kill them? Yay, science!

  • alejandro ramirez nicolas

    exelente informacion fotos reportajes solo una cosa para paises latinoamericanos deberian ser en español gracias

  • Claudio Chapuisat

    Please, publish in Spanish language also. Thank you.

  • Claudio Chapuisat

    Excellent information, as always very interesting. Please, also publish in Spanish language for Spanish-speaking countries. Thank you

  • estella

    Those sharks may have been “brought up by a bycatch” but the article although clearly says that the net was lowered to 2000 meters!!
    So lower than a normal “regular fishing operation”!!!
    Also you write: “They’d be rolling back and forth on their fat bellies [on the ship], which is really cute, but hard when you’re trying to take a picture of them,”
    What is cute about a fish fighting for a breath and rolling on a boat???
    That’s no science nor research to me, sorry!!!
    You have to study those fish, alive, in their own environment!!! 🙁

  • Akiva Sharma

    “Clerkin collected a few representatives of each shark species he encountered while recording data like length, gender, and sexual maturity. ”
    “I took back a ton of sharks,” he said.
    Is it necessary to take them out of their natural habitat in order to study them?

  • julia

    how are you different than little kids who torture and kill cats and dogs? maybe because you go around bragging about all the rare species you’ve killed and demand our admiration? bunch of psychopaths who use science as a cover up for their abuse.

  • Dona Gray


  • Elena Naskova

    Is “collecting samples” a scientific word for killing?

  • Nicholas L.

    I am 5 years old, and I want to know why the ghost shark is called the ghost shark?

    • Jane J. Lee

      Hi Nicholas! I’m not sure why the ghost shark is called the ghost shark, but I can email the researcher to see if he knows.

  • Ryan

    For anyone who is adamantly against the processes of these Ichthyologists have a few questions:

    How are the people who killed these sharks for science any better or worse then the people who were using these nets to catch food? Why is it that the fish being killed are some how of lesser value? Aren’t they both killed for a legitimate reason? One for food and the other for research?

    Secondly, how else do you suppose these scientist study these sharks? Should they swim down there to 3000 feet below and take pictures of these sharks?

    It’s so much easier to sit behind your keyboard and try to correct the only people doing something productive in this world – the scientist – then to drive out in the middle of the ocean and catch fish no one has ever seen before! Why don’t you become a deep water shark researcher and show them how it’s done?

    I understand we should be good stewards of this world. And that we should try to conserve this population. But from a Utilitarian perspective these actions could be the greater good. The more we can learn form these sharks the better we can be at preserving the species. We can learn more about their habitat, diet, mating habits ect. by analyzing a dead specimen then we could in 100 years just swimming around looking at them!

  • Eugenio Allende

    disculpen mi ignorancia, yo admiro la naturaleza y las creaciones de nuestro padre, es muy importante la investigación, lastima que tuvieron que morir esos pobres animales, la culpa no es solo de uno, a parte de sacarnos las ignorancia de encima creo que deberíamos de respetar el trabajo de los científicos, para eso ellos están, con esto no los defiendo, solo quiero que piensen un poco mas allá, total todo lo que sabemos fue alguna vez investigado, el mismo cuerpo humano esta. la gente que critica solo demuestra su ignorancia y los que apoyan su interés, a mi me interesa mucho y me gustaría alguna ves ser como ustedes. gracias.

  • Jake

    Cool discovery. Theres a lot more life out there then we know.

  • Benton Ward

    its supprising how ignorant people can be. All the comments complaining about how the sharks are “killed for science.” do you all even know what bycatch is? The sharks were caught on accident and and die in the nets. If these scientists werent there to document them, they would just be thrown overboard. Which would be a complete waste. i hope these individuals dont go spreading information that they falsly interpreted.

  • Rexx

    If it was rolling around on its belly, it was not dead. Also, why is there so much “bycatch” in fishing? 1.3 tons- of accidental death?

  • dennis oleary

    I call BS…who goes “fishing” at 4000 feet depth? what commercial fish lives there?

  • Bree

    I suspect by normal fishing the article is referring to deep sea fishing, which is still controversial in my opinion.

    I can’t speak to the funding but we do have ways of getting down there, if not in person. I believe there are at least robotic mechanisms that can get that far.

    The reality is though, science is typically more concerned with knowing and understanding than conservation. If something seems like a good opportunity to study an organism they wouldn’t normally have access to, they’re going to jump at the chance.
    How that sort of research impacts a population or if the fact that these sharks are being brought up in deep sea fishing is a problem doesn’t seem to come up until either public outcry or something bad happens and it becomes very clear that they’re having a negative impact. Preemptive conservation efforts are uncommon in pretty much every field from what I’ve seen. The general idea seems to be that just by studying a creature they’re on the positive end of the spectrum and helping to conserve.

    I would say that’s not always the case, but I also don’t feel that we need to know or understand everything if it means disrupting nature. Not a super popular opinion in the science world.

  • Glenn

    I am in total agreement with Eric. If they were all Bycatch, as Jane states, and they kept and researched only those dead, then my assumption would be those living were released back to the sea correct? Seems to me that if the species is rolling back and forth on deck, they are probably still alive? But you have stated they were bycatch and already dead?? A pile of crap.Commercial Fishing is destructive and Unsustainable – well put Eric!!

  • Kooni

    u can make a lot of money selling those rare sharks


    I’m all for discovering new species and such, but TRAWLING @ 6,600FT seems a bit much. The ONLY things your after at depths like that are elusive and possibly extremely rare species. Orange Roughy my ass at depths like that…they go to maybe 6000 if your lucky and Like other slimeheads, the orange roughy is slow-growing and late to mature, resulting in a very low resilience. They are extremely susceptible to overfishing because of this! Going that extra 600 feet..they knew exactly what they were doing and what would happen.

  • Kayleigh Smith

    This is so fascinating 🙂

  • Dwayne LaGrou

    It is only through the dedicated scientists that we can learn as much as possible about these little understood species. It was through the same kind of research that fishermen were able to redesign their nets to allow species like sea turtles and dolphins to escape through a special door in the net. Maybe they will be able to design them to limit the amount of by catch accidentally caught now. Also, there is extremely important research being done regarding the sharks apparent ability to not get any types of cancer. We are all stewards of this earth and it is through the hard work of researchers that allows us as human beings to live much longer than the typical human did just a thousand years ago. Imagine how much better we as humans will be living in another thousand years!

  • Evey H.

    I don’t care whether or not these were caught fishing or not. They are obviously new species and should be catalogued by science. those who have a problem with that, then stop reaping the benefit science has given mankind. Plain and simple. Otherwise, stop being a stupid hypocrite.

  • Jim McGowan

    There is scarcely a commercial or sport fishing activity that does not involve some level of “bycatch” — the capturing/killing of a non-target species. In SOME developed countries, quotas are set on bycatch as well as on the target species. In these fisheries, when you reach a certain level of bycatch, you must cease all fishing activity. This motivates the fishermen to devise fishing techniques that result in less bycatch, so they can continue to harvest the target species. There is progress here. But developing nations have not gotten on board on this — they are still trying to feed their populations. And the pirate nations, most notably Japan, view the ocean and its inhabitants (fish and sea mammals) as an unlimited buffalo herd that they can wantonly vacuum up without regard to any consequences.

    What to do? If you are in the US, write to your Senator and urge him/her to vote to ratify the United Nations Convention on the Law of the Sea. While the US helped with the drafting of this treaty, in 1982, it has still not signed off on it. The Republican minority in the US Senate continues to block ratification.

    Whether you are in the US or not, pressure your representatives to commit to setting and abiding by sustainable fisheries management goals. While that latter phrase is ambiguous, such a commitment opens the door to a process and dialog that can be helpful in the long term.

  • Geogroom

    It’s not like the scientist were on the pissing boat and I highly doubt the fishermen gave a crap whether the fish died or not.


    Amazing shark

  • Loren

    I would be inclined to believe that fishing at 6600 feet is a bit fishy…I would also think any creature brought up from that depth pressure wouldn’t survive even if released immediately.

  • aurelio ordonez talob

    marami pa palang isda ang di pa nakikita sana up date nyo ako pag may bago salamat po.

  • Dan

    My my my. You green bleeding hearts need to just die or something. Commercial fishing while seemingly destructive and unnecessary is just about all we have to work with.. Fish farms are a viable addition to this to minimise the load on commercial fisheries.. but if u take out these commercial fishing endeavours you don’t have fish in the markets or making it to your plates. and then jobs are lost.. lively hoods gone. families destroyed. there is always a bigger picture than what’s in front of your noses. Science is a wonderful thing and scientists having access to these species whether its in bycatch or targeted species is an awesome thing. Having said that though, Trawling at that depth? really common. 6600 feet is a bit of a “clutching at straws” escapade. still wonderful to see species that are rarely seen.

  • Duane Fonseca

    Guess the devil shark is called so cause nature decided to a pull a few strokes together all by itself instead of relying on us humans to add a bit of ominous fiction to make a somewhat natural living thing. Imagine this turning up in one of those Jaws films… in that scale of course… would scare the living daylights out of the bravest of braves ahahahaha!!!

  • David Williamson

    To those of you referencing the comment about the filetail catshark rolling around one the deck of a fishing vessel out at sea, LOOK AT THE PICTURE OF THE SHARK! Any Vessel out at sea, no matter what the size, pitches and rolls with the waves. I can understand how an already dead shark like that would roll around on the deck. Before you condemn someone, pay attention to all of the available information.

  • James K

    There are a lot of misinformed comments on this article. First off, it has been stated many times that the sharks that were documented by Paul were DEAD when they arrived at the surface. Paul did not kill them or catch them with the intent of letting them suffer a cruel death. If some came up that were alive, they died shortly afterwards. These sharks would have been thrown overboard anyway and wasted. Paul was graciously allowed onto a commercial fishing vessel (which don’t always allow outside observers onboard), so that he could document what is being caught out there. Scientists have no idea what species of sharks, rays, and chimaeras are being caught is this area of the world. If we do not know what exists where, then it is next to impossible to protect these species.

    Another common point being made is that commercial fishing is a destructive and bad thing. This is not necessarily the case. Fishing provides people and communities with jobs and food, especially in developing countries. Are you going to tell someone that they can’t fish for something that will feed their family? If you were in their shoes, would you let your children starve because someone half-the-world away said, “You shouldn’t do that, it is bad for the environment?” I know that if my life depended on it, I would fish for my sustenance. Instead of decrying fishing as a terrible thing, we should educate local communities on the damage that unregulated fishing can do for their livelihoods.

    Also, commercial fishing is not a wholesale slaughter of species. Especially in the U.S. and Europe there are strong regulations on what can and can’t be taken. Bycatch is unfortunately hard to control, especially with bottom trawlers, but mankind is making amazing progress in creating nets that exclude certain species from being caught.

    As for farming species, this is not always a good thing or practical. It is true that fish farms can alleviate the loads on commercial fisheries and can help sustain species, but aquaculture farms have also been shown to destroy local ecosystems by allowing large amounts of waste material into the area. In some farming practices, this biological waste from the farmed fish can cover bottom habitats and suffocate the local environment, thereby killing everything in the area. Also, it is not practical to try and farm certain species. Deep water species cannot survive in surface farms, and some species need large expanses of open water to survive, which is not provided by a farm.

    Another common comment is that there is no reason to fish down to 2,000 meters. The fishing vessel in this study was specifically targeting roughies and alfonsinos, which occur at that depth. To fish at shallower depths would result in no targeting fish being caught, which makes no sense to those people who are commercially fishing for these species. As for why scientists cannot just go down to the bottom of the ocean and take pictures of the sharks instead of catching them, it is money. It is incredibly expensive to send a submarine down to look at the species in their natural environment, let alone a research station at the bottom of the ocean! Even if researchers get grant money to do this, the species might just avoid that large, noisy, brightly-lit vehicle that comes up to them. Scientists can’t get much information out of a species that avoids them.

    I urge those reading this article to think critically about what is being said here and not just spout out with uninformed, biased opinions. Ask intelligent, thoughtful questions. If you ask questions and still do not like what you see, then try to make a difference by writing to politicians and informing the public in considerate ways. Do not just yell from behind a keyboard at someone who is trying to better understand the natural world for the betterment of mankind, so that we may eventually be able to protect Western Indian Ocean sharks, rays, and chimaeras.

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  • G R H

    You stated that these sharks were caught by fishermen. What I don’t understand is what species of fish those fishermen were looking to catch at 4,200 feet. What viable food fish are caught that deep. Something doesn’t seem right. Were your calculations off? I hope so.

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