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:
Long conical snout. Large blue/black eyes. Lower jaw contains multiple rows of
inwardly curving teeth. Pectoral
fin length shorter than length of head.
Juveniles often have more rounded dorsal and pectoral fins. Well developed
caudal keel. Crescent shaped tail. Back coloration bright blue to purple/slate
grey. Underside off white. In the Shortfin Mako Shark population of the Azores
and Cape Verde Islands the underside of the snout and jaw of large adults are
dusky which is similar to the Longfin Mako's coloration but characteristic
analysis confirms that they are definitely Isurus oxyrinchus.
Maximum recorded size 4.45m but more commonly 2m. Size at birth 60-70cm
and oceanic in depths of up to 500m.Prefers clear water over turbid.
Often seen swimming just below the surface with first dorsal fin visible.
and distribution: Circumtropical
and temperate in waters usually warmer than 16 degrees. Highly
migratory with migrations recorded up to 2500mi.
Diet and Behavior:The
shortfin mako shark cruises
open water in search of prey species.
It's main diet consists of bony fishes and squid. Wounds and scars on the ventral
surface and caudal peduncle of swordfish and tuna indicate that Shortfin Mako
Sharks often attack from below. As well as a large assortment of bony fishes,
Makos also consume a variety of sharks and rays (especially in South Africa) and
larger specimens may attack dolphins and small cetaceans.
Recorded litter size 2 - 10 but may be higher. Gestation has been estimated at
Shortfin Mako Shark Fetus
On a recent trip to Guadalupe
Island I watched a small (1m) Shortfin Mako shark
repeated passes at the shark cage whenever the Great White Sharks disappeared.
Longfin Mako (Isurus paucus). The longfin mako shark is distinguished
from the shortfin mako shark by its significantly
longer pectoral fins, even larger eyes and dark coloration on the underside of
the snout and jaw extending about half way to the gills. Its teeth are also somewhat
Reaction to divers:
Initially makes fast, close passes in the presence of chum then slows
down and retreats to a more wary distance but continues to make occasional
passes. Otherwise difficult to approach. Rarely attacks without provocation but
has bitten divers and swimmers. Also known to attack boats.
Chris Fallows runs an ecotourism operation in South Africa in which Mako and
Blue Sharks are commonly seen.
Until recently there were Blue/Mako Shark operators working out of Southern
California but due to over-fishing fewer and fewer sharks attended the feeds
until shark watching trips were no longer viable.
Divers working fom their own boats should be able to find shortfin mako sharks
by chumming off shore around San Diego CA. Mako sharks generally migrate through
during the mid to late summer months. People interested in trying this should
head about 10 miles from shore and drift chum around the drop offs where cold
water upwellings bring the sharks up to feed on migrating fish.
Other diving locations submitted by
Mako Sharks. Alessandro De
Sharks of the World. Leonard
and Rays - Elasmobranch Guide of the World. Ralf M. Hennemann. IKAN.