Deep Sea Monsters: The Hagfish

(Photo credit: Gatsbys Monologue)

(Photo credit: Gatsby's Monologue)

When asked to name a fearsome sea creature, common predators such as the Great White Shark and the Killer Whale come to mind. But what about the Hagfish?

What on earth is a Hagfish? The Hagfish (Myxine glutinosa) is an extant primitive creature that inhabits the cool or deep parts of all the oceans in the world. There are currently over 35 species of the Hagfishes and some can even be found in areas that are over 2400m deep1. Hagfishes are nearly blind and they find their way with their highly developed sense of smell. can grow up to a metre long, even though some species are usually about 20cm long. While the Hagfish may look like an eel, it is actually a closer relative to lampreys and than it is to eels and fishes2. Even though this little creature does not give the best of first impressions, its appearance certainly reveals nothing of what it is capable of doing.

The Hagfish consumes worms and dead carcasses from the seabed. However, it has also been documented to penetrate the gills of fish much larger than itself, and then eat them from inside out3. The Hagfish feeding behavior of the Hagfish is so unique that it deserves an article in its own right. However, in addition to its peculiar feeding habits, the Hagfish is also notorious for its defense mechanism. Unlike other sea creatures that uses common tactics such as disguise to hide from their predators or toxin to immobilise their predators, the Hagfish has a totally different way of coping with predators: Slime.

(Photo credit: Journal of Young Investigators)

(Photo credit: Journal of Young Investigators)

When provoked, the Hagfish secretes small amounts of mucus via the hundreds of slime pores found all along its body. Once the mucus comes into contact with water, an amazing chemical reaction takes place and a few millilitres of mucus can quickly turn into a few hundred mililitres of slime. It has been documented that an adult Hagfish can produce over 20 litres of slime in just 5 to 6 minutes4. Predators preying on the Hagfish risk getting their gills clogged by the slime and choking to death. The hunted now becomes the hunter and can easily devour its “predator” from inside out.

Take a look at how good this small creature is at producing slime:

Fun facts:
1. The Hagfish is ranked as one of the “Top 10 Animal Gross-Outs” by Animal Planet5.
2. Fear Factor has used the Hagfish in one of its episodes where contestants have to transfer the Hagfish out of a glass box, all the while being submerged inside the tank of slime which the Hagfish are producing.

Fear Factor – Hagfish Transfer (YouTube)


  • [1]^ Martini, F. H. (1998) The ecology of hagfishes. Cambridge: International Thomson Publishing
  • [2]^ Creatures of the Deep Sea – The Atlantic Hagfish (retrieved on 06 April 2010)
  • [3]^ Tree of Life – Hagfishes (retrieved on 06 April 2010)
  • [4]^ Downing, S.W., Salo, W.L., Spitzer, R.H., Koch, E.A. (1981). The hagfish slime gland: a model system for studying the biology of mucus. Science, 214, 1143-1145.
  • [5]^ TOP 10 ANIMAL GROSS-OUTS : Hagfish (retrieved on 06 April 2010)
  • Male/Female or what?

    Clownfish or anemonefish, Amphiprion sp are fishes from the subfamily Amphiprioninae in the family Pomacentridae.

    Many people do not kclownfishnow that clownfish are actually transsexuals! Clownfish are hermaphrodites that have both female and male gonads. Once the clownfish are hatched, the female gonads are suppressed and so all clownfish start life as males, no females.

    After the early part of their lifecycle, upon finding a suitable host sea anemone, clownfish will settle down on it. The clownfish will gently touches the anemone’s tentacles over a period of several hours or days, until they form a layer of mucus that is resistant to the stings. Usually, a small group of clownfish live in one large sea anemone. And in each sea anemone, there exists a strict hierarchical system between the clownfishes. The highest rank is the female breeder, following next is the male which mate with the female breeder. Only one male clownfish ( which is ranked number two) mate with the female breeder. And at the bottom of the ranks will be up to four smaller, non breeding clownfishes.

    clownfish on flickr

    Ocellaris clownfish HD video at Haus des Meeres on Flickr – Photo Sharing!

    And when the female clownfish die, her mate changes sex and becomes female! At the same time, the largest of the non-breeding clownfish becomes the functioning male. Other fishes also moved up a rank. Another interesting obervations is that clownfish regulate their size in order to remain in the community. Each clownfish will keep its size smaller than the clownfish directly above its rank. Clownfish that grow bigger than clownfish above its rank could be rejected by the community. This adaptation of clownfish ensure continuous reproduction.


    ” Social hierarchies: Size and growth modification in clownfish,” by  Peter Buston. Nature 424, 145-146, 10 July 2003 URL:

    (accessed on 07/04/2010)
    “Nemo puts clownfish in spotlight,” by Ann Kellan. CNN, Monday, August 4, 2003 URL:

    (accessed on 07/04/2010)
    “Ocellaris clownfish HD video at Haus des Meeres” by john.nousis. flickr from yahoo URL:

    (accessed on 07/04/2010)

    “Splash Zone Coral Reef Animals” by montereybayaquarium      URL:

    (accessed on 07/04/2010)

    “Cave under Ras Muhammad” by Leigh Cunningham. X-ray MAG57,58 ,2008   URL:

    (accessed on 07/04/2010)

    “Clownfish” by beest. flickr from yahoo URL:

    (accessed on 07/04/2010)