Not just Shark
Pictures: Elasmodiver contains photos of sharks, skates, rays, and
chimaera's from around the world. Elasmodiver began as a simple web
based shark field guide to help divers find the best places to
encounter the different species of sharks and rays that live in
shallow water but it has slowly evolved into a much larger project
containing information on all aspects of shark diving and shark
There are now
more than 5000 shark pictures and sections on shark evolution,
biology, and conservation. There is a large library of reviewed
shark books, a constantly updated shark taxonomy page, a monster
list of shark links, and deeper in the site there are numerous
articles and stories about shark encounters. Elasmodiver is now so
difficult to check for updates, that new information and pictures
are listed on an Elasmodiver Updates Page that can be accessed here:
Bluntly rounded snout. Seven gill slits, posterior slits very short. Single
dorsal fin set well back on body. Upper body sprinkled with small black spots
and usually some white spots. Large size.
At birth 34-45cm. Males mature at 130-170cm. Females mature at 200cm. Maximum
recorded size 290cm. May possibly grow to 400cm.
Coastal sandy bays and rocky shorelines up to the surf line.
Larger individuals inhabit deeper channels. Recorded at 136m but usually found
and distribution: Temperate
coastal waters around the world. Southern Australia, New Zealand, Japan,
Southern Africa, east and west coasts of south South America, and west coast of
North America to Alaska.
Cruises steadily along bays in search of food moving in and out with the tides.
Prefers low visibility - night, turbid water, overcast conditions. Known to
aggregate possibly for mating. Footage from the documentary Shark Quest shows a
group of Broadnose Sevengill Sharks feeding together on a stingray carcass.
Preys on sharks and rays, bony fishes and marine mammals.
Litter size 67-104. but may be higher. Gestation probably around one year
followed by one year of recovery.
Broadnose Sevengill Sharks have been observed spy hopping - holding their heads
above water and seeming to look around. This behavior is rare among sharks but
has been regularly observed in Great White Sharks. It may be an adaptation
to aid in the capture of marine mammals.
The IUCN lists this shark as 'Data Deficient'. However the IUCN notes that the
broadnose sevengill's flesh is sought after in some markets. It is also taken in
some areas for its hide and liver oil. Intensive commercial and sports fisheries
in San Francisco Bay targeting it for its fine meat caused a marked local
decline in numbers during the early 1980s. It is utilised in China for its skin
and liver. Pollution may be a possible threat to inshore bays which are
Although wide ranging in temperate waters and moderately common where not
heavily exploited (e.g., southern Africa), this large shark has a limited
inshore bathymetric range in heavily fished temperate waters and is often
concentrated in shallow bays. This exposes it to intensive inshore bycatch and
sometimes targeted commercial, sports and semi-commercial fisheries over most of
its range, particularly off China, California, Argentina, Namibia and South
Africa (Compagno in prep. a). Catch statistics are not reported, except for the
west coast of the USA, which show a peak in landings of 1.55 t in 1981 with a
sharp decline to less than 0.1 t in 1986 (Compagno in prep. a).
The Bluntnose Sixgill Shark (Hexanchus griseus) has a very similar body
shape but lacks the seventh gill slit and has less or no spots. The Sharpnose
Sevengill Shark (Heptranchias perlo) has much larger eyes, a more pointed
snout, and flattened, elongated pelvic fins.
Reaction to divers:
The Broadnose Sevengill sharks tend to ignore divers but they will turn and swim
away when intercepted. Sevengills can become aggressive in baited situations e.g.
towards spear-fishermen. In captivity it has bitten aquarium divers.
Although this shark has a broad distribution it is not commonly encountered by
divers in most areas. However, Miller's Point off of Simon's Town
near Cape Town, South Africa offers extremely reliable sightings.
Sevengill shark sightings along the coast of Southern California are also
increasing. La Jolla Cove is a particularly good site where multiple sharks can
sometimes be seen on a dive. Divers sometimes carry bait in this area to
Other colloquial and foreign names for Notorynchuscepedianus: