Not just Shark
Pictures: Elasmodiver contains photos of sharks, skates, rays, and
chimaera's from around the world. It began as a simple web based
field guide to help divers find the best places to encounter
different species of sharks and rays but it has slowly evolved into
a much larger project containing information on all aspects of shark
diving and photography. There are now more than a thousand shark
pictures and sections on shark evolution, biology, and
conservation. There is a large library of reviewed shark books, a
constantly outdated shark taxonomy page, a monster list of shark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:
If you're looking for a
broader range of marine life pictures the following links represent
a new area that contains pictures on other marine organisms and on
marine habitats. This expansion of Elasmodiver is in its first
stages but will eventually include pages on everything from sea
stars to nudibranchs. Creating this portal will take time and for
now it consists of a token offering of fish pictures. Please return
regularly to enjoy the progress.
Identification:
Black
tips of pectorals, second dorsal, and lower caudal fin. All other fins may also
be edged in black or appear dusky. Snout long and pointed. Upper body gray to
light gray with a white streak present from above the pectoral fins
backwards joining the white underbelly half way to the tail. No interdorsal
ridge. First dorsal fin high and pointed.
Size:
Maximum
length 260cm. Size at birth 38-72cm.
Habitat:
Turbid inshore waters, lagoons, reef channels, reef drop offs and
seamounts. To 30m.
Abundance
and distribution: Circumtropical
and subtropical.
Behavior: Diet
consists primarily of fish including small sharks and rays. Also consume
crustaceans and snails and octopus. At Rangiroa the Blacktip passes out of the
lagoon on the ebbing tide to cruise the reef face. More active during daylight
hours.
Reproduction:
Viviparous.
Recorded litter size 1 - 10. Gestation period 11 - 12 months.
Observations:
Photographs:Walkers
Cay, Bahamas.
Similar species:
In the Caribbean the Blacktip is often confused with the Caribbean reef shark (C.perezi)
which is not as slender and long in front of the eyes and has a less pronounced
white stripe on its flank. Many other Carchhinids around the world are also hard
to distinguish from the blacktip shark. Commonly seen species include the Grey
reef (C.amblyrhynchos) and the Galapagos shark (C.galapagensis).
Fin tip coloration and proportion is the best clue.
Reaction to divers:Varied. Usually shy but during some
encounters the Blacktip shark can become aggressive making close passes and
bumping divers.
Diving
logistics: This
wide ranging species may be seen in a variety of locations. Drift dives
organized at Rangiroa Lagoon are often well populated with blacktips. The
chumsicle dive at Walkers Cay in the Bahamas is the best location in the
Caribbean to get very close to this shark.
Other diving locations submitted by
readers:
References
and further
reading:
Sharks of Tropical and Temperate Seas. - R.H.
Johnson - Pisces Books
Reef
Sharks and Rays of the World. Scott W. Michael. Sea Challengers.
Sharks
and Rays - Elasmobranch Guide of the World. Ralf M. Hennemann. IKAN.
