Pacific Hagfish

Pacific Hagfish, Eptatretus stoutii

Pacific Hagfish, Eptatretus stoutii. Fish provided by the commercial fishermen of the greater San Diego area, San Diego, California, October 2014. Length: 25 cm (10 inches).

The Pacific Hagfish, Eptatretus stoutii, is member of the Hagfish or Myxinidae Family, and is known in Mexico as bruja pintada. Although they are not eels, they are commonly known as Slime Eels, and have developed a reputation for being the “most disgusting” of all sea creatures due to their unusual feeding habits and slime-producing capabilities. The Hagfish represent an ancient extremely primitive form of life and have remained virtually unchanged since the Paleozoic Era, 450,000,000 years ago, when fish first evolved. Globally, there are seventy-eight members of the Myxinidae Family that have been placed in six genera, of which four are within the genus Eptatretus, and all four are found in Mexican waters of the the Pacific Ocean.

The Pacific Hagfish has a cylindrical elongated body that move in a snake-like motion using their paddle-like tail. They are uniformly colored ranging from tan to brown or gray dorsally and being slightly lighter ventrally. They have a white area around their gill openings. They are a cartilaginous fish that lacks scales, paired fins, a stomach, and true jaws. Their eyes are rudimentary (eye spots) and are only capable of detecting light. They have a keen sense of smell and touch. Their jawless mouth contains 2 parallel rows of pointed keratinous teeth, which are secured to rasp-like dental plates. They have a series of barbels around their head that are used as sensory organs to detect food. They have a row of 10 to 14 pores or slime glands on both sides of their body. When agitated, they are capable of producing copious amounts of slime in a very short period of time which they use as a strong defense mechanism to avoid predation. They also have the ability to tie themselves in a knot, also to avoid predation.

The Pacific Hagfish is a demersal species that is found from the mesopelagic to the abyssal levels on the continental shelves and upper slopes of the ocean in and around silt and clay bottoms at depths between 17 m (55 feet) and 1,158 m (3,800 feet). They are most active at night and spend their days in burrows with their heads exposed. They reach a maximum length of 82 cm (2 feet 8 inches). They are opportunistic feeders with a keen sense of smell that attack dead or dying fish and marine animals that descend from the pelagic zone in massive schools. They burrow into their prey by making a hole with their rasp-like teeth or enter through an existing opening to consume their prey inside out, leaving only the skin and bones behind when they are done. They also have the ability to absorb nutrients through their skin, which is unique among all 50,000 vertebrates. They are believed to be the culprit behind partially eaten fish taken by longliners and related fish gear, used for example by the halibut commercial fishery. They consume polychaete worms and other bottom fauna on a limited basis. As such they play an important role in the ecosystem enhancing global cycles of carbon, nitrogen, and phosphorous. They have a slow metabolism and can survive for up to 7 months without eating. They are preyed upon by California Sea Lions, Northern Elephant Seals, and Harbor Seals and their eggs are preyed upon by Sablefish, Elephant Seals, and other Pacific Hagfish. Males are slightly more abundant than females. They reproduce via external fertilization with each female producing between twenty and thirty eggs per annum. The Pacific Hagfish The Acapulco Damselfish is poorly studied with very limited information available about their lifestyle and behavioral patterns including specific details on age, growth, longevity, movement patterns, diet, habitat use, and reproduction.

The Pacific Hagfish is is a resident of Mexican waters of the Pacific Ocean but has a limited distribution being found from Guerrero Negro, Baja California, northward along the central and northwest coasts of the Baja.

The Pacific Hagfish is easily confused with a series of other Hagfish, the most common being the Black Hagfish, Eptatretus deani (deeper water; purplish black color; shorter head; lacks white area around gill covers).

From a conservation perspective the Pacific Hagfish is currently considered to be Data Deficient. Due to the heavy demand for hagfish and related heavy fishing pressure, their populations are believed to be in decline. Conservation measures along the West Coast of the United States are not currently in place but are pending. They are a targeted commercial species along the West Coast of North America with fish being caught with deep water traps. Fish are either frozen at sea or maintained live. Frozen fish are exported to Asia at a level of 800 tons annually (with about 65% of the fish being Pacific Hagfish) for the production of leather goods. Live fish are sold at ethnic markets along the West Coast of the United States. They are occasionally caught by recreational anglers. Hagfish skin is used to produced “eel skin” clothing, belts, and other accessories. There has been new interest is the use of hagfish slime as a replacement for artificial materials such as nylon to produce more environmentally friendly products such as women’s clothing and in microsurgery for sutures.

Please join us on October 20 to share in the celebration of National Hagfish Day!