Pacific hagfish

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Pacific hagfish
Pacific hagfish Myxine.jpg
Conservation status
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Myxini
Order: Myxiniformes
Family: Myxinidae
Genus: Eptatretus
Species: E. stoutii
Binomial name
Eptatretus stoutii
(Lockington, 1878)

The Pacific hagfish (Eptatretus stoutii) is a species of hagfish. It lives in the mesopelagic to abyssal Pacific ocean, near the ocean floor. It is a jawless fish, a throwback to the Paleozoic Era when fish evolved. Deep-sea diving equipment is known to have been fouled by large amounts of hagfish slime near the bottom of the ocean, extruded by the eel-like fish when they are alarmed.

The hagfish is notorious for its slimy skin. When disturbed, it oozes proteins from slime glands in its skin that respond to water by becoming a slimy outer coating, expanding it into a huge mass of slime. This makes them very unsavory to predators. Hagfish create large amounts of slime in just minutes. One scientist researching this protein excretion concluded that a single hagfish could fill an entire barrel with slime in less than 100 minutes.[1]

In many parts of the world, including the US, hagfish-skin clothing, belts, or other accessories are advertised and sold as "yuppie leather" or "eel-skin"[2] (hagfish are not true eels, which are bony fish with jaws).

The hagfish is eaten in Korea and other Asian countries, along with its eggs and its slime. The section of the fishing industry devoted to hagfish-fishing has grown in recent years.

The hagfish has feelers that enable it to find food more easily. It is an opportunistic feeder, and eats dead and rotting animals that float down from the pelagic zone of the ocean. Swarms of hagfish will descend upon and penetrate the carcass and devour it from the inside out. This mode of marine waste disposal allows the hagfish to efficiently gain nutrients. The resultant rarity of rotting animals on the sea floor is one of the factors that modulates global cycles of phosphorus, carbon and nitrogen.

This fish is often referred to as the "slime eel". This is an incorrect common name / nickname.

Eating habits[edit]

The pacific hagfish has a property of being able to absorb nutrients through its skin; it is unique among all 50,000 vertebrates, and it is believed that is the closest animal we can get to the first vertebrate. The fish burrows into dead carcasses, exposing its skin to super nutrient-rich decomposing matter, and eating away at the dead animal. Chris Glovet, at the University of Canterbury in Christchurch, New Zealand, tested his theory by putting skin samples of the hagfish in between nutrient rich seawater and a solution similar to the hagfish's body fluids. They found out that in fact amino acids flowed right through.[3][4]

Pacific hagfish at 150 metres' depth, Cordell Bank National Marine Sanctuary, California.

Fertilisation[edit]

Hagfish have both male and female specimen and they fertilise their eggs externally meaning they fertilise after the female lays her eggs. On average females lay about 28 eggs over five millimetres in diameter and they carry them around where ever they swim. However, females try to stay in the dens that they burrowed to ensure the protection of their eggs and the protection of themselves.[5]

Hagfish slime[edit]

The Pacific hagfish produces prodigious quantities of slime and particularly, it seems, when responding specifically to situations where it serves as protection, or more generally to stress. The Pacific hagfish creates its thick, gooey slime by opening a valve that scientists believe pushes water into its olfactory organ. The slime is notoriously difficult to remove from fishing gear and equipment. Because of the slime they make, Pacific fisherman, who collect hagfish to sell in Asian markets to use as leather or food, have nicknamed the creature the slime eel.[6]

References[edit]

  1. ^ Muse magazine, 2006
  2. ^ Barss, William (1993), "Pacific hagfish, Eptatretus stouti, and black hagfish, E. deani: the Oregon Fishery and Port sampling observations, 1988-92", Marine Fisheries Review (Fall, 1993), retrieved April 21, 2010 
  3. ^ Bucking, Carol. "Digestion under Duress: Nutrient Acquisition and Metabolism during Hypoxia in the Pacific Hagfish.". Retrieved 6 December 2011. 
  4. ^ Barras, Colin. "The hag with impeccable table manners". Retrieved 6 December 2011. 
  5. ^ Barbs, William. "Pacific hagfish, Eptatretus stouti, and black hagfish, E. deani: The Oregon fishery and port...". National Marine Fisheries Service. Retrieved 6 December 2011. 
  6. ^ Theisen, Birgit. "The Olfactory System in the Pacific Hagfishes Eptatretus stoutii, Eptatretus deani, and Myxine circifrons.". Blackwell publishing. Retrieved 6 December 2011.