Not just a
huge collection of
Elasmodiver.com contains images of sharks, skates, rays, and a few
chimaera’s from around the world. Elasmodiver began as a simple web
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 photography.
now more than 10,000 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
Snout laterally pointed.
Well developed labial furrows. Eyes small and round. Interdorsal ridge absent.
Dorsum grey with indistinct white line on flank. Ventrum white. Distinct
and boldly delineated black tips on all fins except pelvic and upper caudal.
Anal fin more ‘hooked’ than in most large reef sharks. Angular torso with well
defined lateral line. Teeth narrow cusped.
length 278cm. Size at birth 60-75cm.
Continental coastlines from inshore to edge of shelf. Surface waters to bottom
at 75m. Also above surface when breaching!
and distribution: Western Atlantic from
Carolinas to Gulf of Mexico. Also southern Brazil. Occasional Caribbean and
northern Brazil. Eastern Atlantic around western Africa and Southern
perimeter of Indian Ocean from Madagascar to South Africa. Also India, South
East Asia and Australia. North Pacific Japan and Philippines.
to undertake mass migrations; aerial footage of enormous
schools of spinner sharks off of eastern Florida have been used by the media to
exaggerate the dangers of beach swimming. When feeding, vertical upward attacks
on surface fish sometimes lead to spectacular spinning jumps from the water,
hence common name.
Diet: consists mainly
of bony fishes but some stingrays and cephalopods are also consumed.
Yolk sac placenta. Recorded litter size 3 to 15. Litter size increases with size
Gulf of Mexico, Louisiana,
Because of its extensive range it is difficult to list every carcharinid shark
that looks somewhat similar to Carcharhinus brevipinna. Field
identification is difficult but the spinner shark’s highly laterally pointed
head, distinct black fin tips (except anal and upper caudal) and unique
breaching behavior are a good place to start.
Reaction to divers:
The spinner shark is very hard to approach. Although it is commonly seen by
fishermen when breaching, it quickly moves away when divers enter the water. The
grainy image above was taken from a distance while surface snorkeling with a
large school of silky sharks. Two spinners were attracted by the chum slick but
they refused to approach the bait and stayed far below the much bolder silkies.
Video from Western Australia indicates that spinner sharks grow much more
aggressive around bait balls and may ignore divers completely.
IUCN Red List status: Near threatened. Vulnerable to fishing
pressure and habitat degradation.
logistics: Please email elasmodiver with information on sites where
scuba diving or snorkeling with spinner sharks is possible.