(DRAFT) - Taxonomy
Species hagfish, Atlantic
Species Id M010135
Date 27 AUG 96
TAXONOMY
NAME - hagfish, Atlantic
OTHER COMMON NAMES - Atlantic hagfish, northern hagfish, hagfish, slime eel and Fr. myxine du nord
ELEMENT CODE -
CATEGORY - Fish
PHYLUM AND SUBPHYLUM - Chordata, Vertebrata
CLASS AND SUBCLASS - ,
ORDER AND SUBORDER - Myxiniformes,
FAMILY AND SUBFAMILY - Myxinidae,
GENUS AND SUBGENUS - Myxine,
SPECIES AND SSP - glutinosa,
SCIENTIFIC NAME - Myxine glutinosa
AUTHORITY - Linnaeus, 1758
TAXONOMY REFERENCES - 258 and 1717
COMMENTS ON TAXONOMY -
A small family of ancient, bottom-living jawless marine fishes inhabiting
deeper parts of the shore waters of temperate seas of the world; principally
on continental shelves and slopes, near or on muddy bottoms, where they feed
on dead and dying fishes and invertebrates. They may also attack living
prey. Unlike the lampreys, they are hermaphroditic and have no larval
stage. Upon hatching from the egg, the young resemble the adults.
Five genera with about 32 species; only 1 species occurs in the Canadian
Atlantic area.*258*
Taxonomy - 1 (DRAFT) - Status
Species hagfish, Atlantic
Species Id M010135
Date 27 AUG 96
STATUS
REFERENCES FOR STATUS - 258
COMMENTS ON STATUS -
The Atlantic hagfish is of no direct commercial importance, but is does
constitute a nuisance to commercial fishing activities since it attacks and
eats dead and dying fishes caught on line trawls and in bottom gill nets,
destroying such fishes for commercial use. Attacks on commercially caught
fishes occur principally when the gear is on the bottom.
It is of importance in biomedical reseach and has been studied extensively,
mainly because it is the most primitive of living vertebrates. Detailed
knowledge of its biology, especially its physiology, may aid in our
understanding of the evolution of fishes. It also has three hearts, one
without nerves. Studies of these and other organs have been conducted in
hopes of providing insight into cardiac function and activity in mammals.
Detailed studies of blood chemistry, endocrine system, and immune responses,
to name only a few areas of interest, have been made.*258*
Status - 1 (DRAFT) - Distribution
Species hagfish, Atlantic
Species Id M010135
Date 27 AUG 96
DISTRIBUTION
Distribution - 1 HABITAT ASSOCIATIONS
HABITAT - MARINE
REFERENCES FOR HABITAT - 258
LAND USE -
Bays and Estuaries
Water
REFERENCES FOR LAND USE - 258
COMMENTS ON HABITAT ASSOCIATIONS -
Atlantic hagfish live on soft, muddy bottoms, usually in depths of 30 m
or more, at times to a depth of 958 m. They require the high-salinity
(about 30 ppt or more) and low-temperature (below 12 degrees C)
conditions usually found in deeper waters. Aquarium observations
indicate that they burrow in the soft bottom and may assume a position
with the head emergent from the bottom. However, they may also remain
completely buried in mud for long periods, suggesting that the species
is facultatively anaerobic. Certainly they may remain inactive for
long periods. They are nocturnal, being more active at night than in
daylight hours, although they are blind.
They must be quite abundant in certain locations, such as in
Passamaquoddy Bay, NB, judging from the number caught in traps. A trap
made from a 25 gal. steel drum, baited with flounder and set overnight
in 50 m, may catch upwards of 500 or more hagfish in a single
night.*258*
ANIMAL/PLANT SPECIES ASSOCIATIONS -
Predation and Competition: The Atlantic hagfish has few known enemies,
although small hagfish have been found in the stomachs of cod and white hake
and six hagfish eggs were taken from the stomachs of halibut caught over
eastern Sable Bank. It would seem to be risky for a cod, however, to
attempt to eat a large adult hagfish because of the great quantities of
viscous slime hagfish can produce. Indeed, the production of large
quantities of slime may be related to feeding, for a fish predator, upon
grasping a hagfish in its mouth, would likely find its mouth and gills
suffused with the viscous, suffocating slime, which could cause death, thus
providing the intended victim with a meal. As a scavenger, the hagfish must
compete with other creatures of similar food habits, such as crabs, that
also feed on dead organisms found on the ocean floor.*258*
Habitat Associations - 1 (DRAFT) - Food Habits
Species hagfish, Atlantic
Species Id M010135
Date 27 AUG 96
FOOD HABITS
TROPHIC LEVEL -
SCAVENGER
REFERENCES FOR TROPHIC LEVEL - 258
LIFESTAGE FOOD FOOD PART
General Polychaetes Not Specified
General Crustaceans Not Specified
General Fish See Comments
General Malacostraca Not Specified
Important Crustaceans Not Specified
REFERENCES FOR GENERAL FOOD - 258
COMMENTS ON FOOD -
Food: Atlantic hagfish comsume the internal organs and flesh or dead and
dying creatures found on the sea floor. They will attack, burrow into, and
eat fishes caught on bottom longlines or bottom gill nets. The fishes are
attacked and entry to the body gained by using the sharp lingual or tongue
teeth in a rasping manner, or by biting onto the skin or the dead fish and
pulling against the bitten skin until a piece is removed; or entry may be
via the mouth or anus, the viscera being eaten first and then the muscle,
leaving only skin and bones.
European studies indicated that many invertebrates, such as polychaete worms
and crustaceans are also consumed.
Few food studies of wild-caught Atlantic hagfishes have been conducted but a
study of gut content over 100 North Sea specimens suggested that the species
may be a more active predator than previously thought. It was found that
shrimp, Pandalus borealis, was an important food item. The evidence
presented suggests that P. borealis was selected and preyed upon by the
hagfish examined. Thus the Atlantic hagfish may be an active predator on
shrimps and possibly other species.*258*
Predation and Competition: The Atlantic hagfish has few known enemies,
although small hagfish have been found in the stomachs of cod and white hake
and six hagfish eggs were taken from the stomachs of halibut caught over
eastern Sable Bank. It would seem to be risky for a cod, however, to
attempt to eat a large adult hagfish because of the great quantities of
viscous slime hagfish can produce. Indeed, the production of large
quantities of slime may be related to feeding, for a fish predator, upon
grasping a hagfish in its mouth, would likely find its mouth and gills
suffused with the viscous, suffocating slime, which could cause death, thus
providing the intended victim with a meal. As a scavenger, the hagfish must
compete with other creatures of similar food habits, such as crabs, that
also feed on dead organisms found on the ocean floor.*258*
Food Habits - 1 (DRAFT) - Environment Associations
Species hagfish, Atlantic
Species Id M010135
Date 27 AUG 96
ENVIRONMENTAL ASSOCIATIONS
Environment Associations - 1 (DRAFT) - Life History
Species hagfish, Atlantic
Species Id M010135
Date 27 AUG 96
LIFE HISTORY
Description: Body elongate, eel-shaped, round in cross section anteriorly,
compressed posteriorly; a single gill pore on each side just anterior to
ventral fin fold origin; line of nucous pores, low on each side of body,
from behind gill openings to beyond anus. Mouth lipless, with one pair of
smaller barbels directed posteriorly and one pair of smaller barbels
directed anteriorly on either side of single nostril at tip of snout;
jawless and toothless, orange-colored tongue (or lingual) teeth present
which can be everted for burrowing into host; eye blind, covered by skin and
layer of muscle. Fins; no paired fins, no fin rays, a fold of skin
resembling a fin begins dorsally about two-thirds back from snout and just
before anus and continues around tail, continuing forward on ventral surface
to about one-third distance behind snout. Size 46-61 cm long, rarely
longer. Color uniformly brown, reddish, or gray above; sometimes mottled.
Reproduction: Spawning apparently occurs throughout the year. Female
hagfish may carry 1-30 horny-shelled large eggs, each up to 25 mm in length.
The eggs are whitish, ovoid in shape, with a cluster of filaments at each
end. Hagfish eggs are seldom found in the wild but have been taken in the
Bay of Fundy, on Georges Bank, and off the south coast of Newfoundland.
Atlantic hagfish are not functional hemaphrodites but each sexually mature
individual possesses undeveloped gonadal tissue of the opposite sex.
Growth: Newly hatched Atlantic hagfish resemble the adults and thus do not
have a larval stage. The smallest individuals that have been seen are about
6.0-7.0 cm long. The rate of growth is unknown and there is no known way to
age them. Specimens taken in Passamaquoddy Bay average about 35.0 cm
TL.*258*
Predation and Competition: The Atlantic hagfish has few known enemies,
although small hagfish have been found in the stomachs of cod and white hake
and six hagfish eggs were taken from the stomachs of halibut caught over
eastern Sable Bank. It would seem to be risky for a cod, however, to
attempt to eat a large adult hagfish because of the great quantities of
viscous slime hagfish can produce. Indeed, the production of large
quantities of slime may be related to feeding, for a fish predator, upon
grasping a hagfish in its mouth, would likely find its mouth and gills
suffused with the viscous, suffocating slime, which could cause death, thus
providing the intended victim with a meal. As a scavenger, the hagfish must
compete with other creatures of similar food habits, such as crabs, that
also feed on dead organisms found on the ocean floor.*258*
Life History - 1 (DRAFT) - Management Practices
Species hagfish, Atlantic
Species Id M010135
Date 27 AUG 96
MANAGEMENT PRACTICES
Management Practices - 1 (DRAFT) - References
Species hagfish, Atlantic
Species Id M010135
Date 27 AUG 96
References
258 * Scott, W.B., M.G. Scott. 1988. Atlantic Fishes of Canada.
Canadian Bulletin of Fisheries and Aquatic Sciences (219) (ed.).
University of Toronto Press Toronto, Canada:731.
References - 1