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the Legacy continues…………………….
Gregory R. Mann, Ph.D. {ret.}

Goblin Shark

“Mitsukurina owstoni”

Goblin Sharks are bizarre, sinister-looking creatures. Growing to a length of over 3.8 meters, they have a soft, flabby body, pinkish-gray color and a peculiar, blade-like snout overhanging long, highly protruding jaws with slender, fang-like teeth. The jaws are highly specialized to rapidly extend and quickly snap up small prey. The Goblin Shark has long, sharp teeth in the front of its jaws used to capture prey; the upper teeth are slightly longer than the lower teeth. Their teeth in the back of their mouth are smaller and used to crush prey. As with other sharks, Goblin Shark teeth are located in rows that rotate into use as needed. They have tiny black eyes that are missing nictitating eyelids found in most sharks, a thin membrane hidden beneath the lower lid of the eye that extends across the eye for protection. The anal fin of this species is large and broadly rounded. Their length at birth is unknown; the smallest free-swimming individual was 1.07 meters long. They reach an average length of about 1.6 meters with the largest on record, a male measured at 3.8 meters; females may grow even larger.

The Goblin Shark is a demersal (dwelling at or near the bottom) to mesopelagic inhabitant of outer continental shelves & slopes found at depths ranging from 40-1,200 meters. They are slow-moving and neutrally buoyant. Many have been caught off Honshu, Japan, at depths of 60-280 meters. They likely use their electrode-sensitive rostrum to detect prey & capture it from close range using a combination of their protruding jaws and pharyngeal suction. They live near the sea bottom in specific locations in the Pacific, Atlantic & Indian oceans. About half of the known specimens were found off Japan, others off the coast of New Zealand and southern Africa. In Australia, Goblin Sharks are found off New South Wales and possibly southern Australia. Records of stomach contents in Goblin Sharks are rare; known prey includes small bony fish, cephalopods and an unidentified crab. This apparently sluggish species feeds in mid-water and possibly on or near the bottom; teeth have been found embedded in submarine cables. 

The Goblin Shark is almost certainly ovoviviparous where embryos feed on yolk sacs and other ova (eggs) produced by the mother and hatch within her body. As in other lamnoids; no pregnant specimen has been collected, thus no data is available on gestation period, number of pups, pupping season or nursery grounds. Males reach sexual maturity at about 2.3 meters, one 3.8 meters specimen had sperm in the seminal vesicles and calcified claspers, indicating probable maturity; no data on size at maturity in females. No data on growth rate, age at maturity or longevity for either sex. The Goblin Shark is fished commercially off Japan and sporadically taken as by-catch while deep-sea long-lining off Portugal. Elsewhere, they are taken primarily as by-catch of deep-water trawls and occasionally with deep-water long-lines, deep-set gill nets and possibly purse seinesThe Goblin Shark is probably harmless, but has rarely been encountered by humans. Although probably common, this species is rarely seen and is thus poorly known; catches should be preserved and reported as soon as possible. This rare species has only been described in the scientific literature about 45 times; half from Japan, the others from New Zealand and southern Africa.

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