Identification:
Hexanchus griseus
have six gill slits (the majority of sharks have only five gill slits)
and with only one dorsal fin set near the tail it is most distinctive.
Mature specimens from 3.5 m to nearly 5 m total length (TL) spend all their
lives in very deep waters from 500 m to 2000 m, with possible excursions
to shallows waters at night to feed but very little is known about their
behaviour. Mainly the juveniles and immature specimens are seen when
caught from close inshore and in deeper waters from depth of 30 m to 500
m. These small specimen are rarely larger than 2.5 m ( 8') TL, @ 91 kg
( 200.5 lb). When I say small, they are compared to a very large
stout bodied, round bluntly pointed headed, mature female of 4.82 m (15.4
feet) TL, and more than 650 kg (1432.6 lb). Smaller in size and
weight among the predatory sharks only to the 7 m Great White shark, and
the deep water Sleeper shark (Somniosus microcephalus) that grows
to 6.4 m, and was also filmed at 2200 m deep.
Colours range from dark
brown to dark silvery grey with large, opalescent eyes.
Breeding:
Biology; Females H.
griseus mature at about 4.20 m to 4.50 m TL. They are ovoviviparous,
which means that the eggs hatch inside the mother body, so the young are
born alive and fully formed. H.griseus has a remarkable high fecundity
(litter size), producing 22 to 108 live pups in every litter at about 0.65
m TL, @ 1.2 kg. A captured female of 4.21 m TL from off Church Rock, California,
contained 51 near term embryos.
Food:
Large, fast moving
prey species, numerous shark and ray species (especially spurdog), any
bony fish ( large deep water hake are a major prey item), squid, crabs,
shrimps, swordfish, cetaceans and other marine mammals.
Range:
This very large but little
known shark is a rare visitor to our coastal waters. A few specimens of
up to 54.3 kg, have been caught recently by boat anglers around Dingle
Bay and Kinsale Bay, County Kerry off South West Ireland.
Habitat:
Found when feeding on the
large stocks of deep water fish in commercial fishing grounds around the
UK. Marine Biologists survey the deep waters for fish and sharks, along
the edge of the continental shelf.
Reports:
16
June 2009
A
rod caught Blunt-nosed Six-gilled
Shark, Hexanchus griseus,
was landed on board the Clare Dragoon
out of Carrigaholt,
County
Clare, south-west Ireland. The fish which weighed in at 480 kg, (1056
lb), beats the existing European angling record which stands at
466 kg and was landed in the Azores.
The
shark was caught
about three miles off Loop Head in County Clare Ireland. I believe the
official length was 12 ft 6 " and weight 1056 lb. It was caught
by a 70 year old man who had it on for 35 minutes . It could not be brought
on board as it was so big so they tied a rope around its tail and towed
it into Carrigaholt pier. I have added some more photos. The guy with his
foot in the picture is a size 12 to give some idea of its size. I think
its gerth was 8 ft.
c.
13 October 2006
Sport
angler Anton Kristiansen
was out fishing with Turid Kvammen
at Smøla, off the coast of Nordmøre, northwest Norway when
he hooked and landed a Six-gilled Shark, Hexanchus
griseus, called kamtannhaiin
Norwegian. It measured 2.5 meters long and weighed 120 kg (264 lb).
This
shark is a deep water predatory species that is rarely caught by commerical
fishermen and even less often by anglers..
BMLSS
Sharks
I saw
A six gill around July 25 1999. It was in the Gulf of Mexico (EB
160A), at 935 ft. I was on bottom in a Hardsuit. It was about
14-15 ft long. The suit video was on, and I do have a copy of it.
The shark came out of the darkness, and passed within a couple feet of
me. The video shows this very clearly, making identification easy.
It was very exiciting.
Russ DeMille (Hardsuit
pilot)
You
may view a 25 foot six gill in streaming video! http://www.subpilot.com
Gary
Montemayor
Deep
Sub Pilot
Research
Submarine Production
1008
E. Mallory St.
Pensacola,
Fl. 32503
fax-419-791-5255
My
name is Damion and I live in Texas. My occupation is commercial shrimping.
I own my own trawler and occasionally
work
between 200 and 300 fathoms. This past March through May 2000 I have caught
and released approximately 12 sharks ranging in size from 8ft to 16ft off
the east coast of Florida,between Ft.Pierce and Ft.Lauderdale. Also on
the south side of Florida, between Key West and Dry Tartugus. But the largest
of the 12 was caught around Desoto Canyon in the Gulf of Mexico south of
Mobile, Alabama and Pensacola,Florida. If I find them any where else I'll
let you know.
Shark Enthusiast
Damion
Additional
Notes:
Bluntnosed
Six-gilled Shark Page 2
Sharp-nosed
Seven-gilled Shark, Hepranchias
perlo
Information wanted: Please
send any records of this fish, with location, date, who discovered it,
how it was identified, prevalence, common name and any other details to
Shorewatch
Project EMail Glaucus@hotmail.com.
All messages will receive
a reply.
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