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constantly outdated shark taxonomy page, a monster list of shark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 nudibranches. 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.
Nurse
shark, Common nurse shark, Atlantic nurse shark.
Latin Name: Ginglymostoma
cirratum.
Family: Rhincodontidae
Identification: Uniformly
brown or gray body, paling slightly towards belly. Two dorsal fins of almost
equal size close to tail. Head bulbous with small mouth. Mouth has a barbell on
each side. Tail narrow with a large upper caudal lobe and no distinct lower
lobe.
Size: 5 to
9ft max. 14ft.
Habitat: Found
in many environments including reef flats, sandy areas, lagoons, and mangroves.
From intertidal to 150ft.
Abundance: This
is the most commonly encountered shark on most Caribbean reefs. It can be
locally common from Florida to Brazil.
Distribution: On
the Atlantic coast of the Americas from Rhode Island to Brazil. Bermuda and the
Eastern Atlantic from Senegal to Gabon. Also in the Eastern Pacific from Baja
California to Peru.
Behavior: Nocturnal.
Sleeps under overhangs of reefs, or in mangroves during the day. Often found
sleeping in small groups. At night forages for spiny lobsters, crabs, octopus,
and sea urchins etc. May inhabit same area for many years.
Reproduction: Ovoviviparous.
Observations: On
one night dive, I observed a Nurse darting in and out of our flashlight beams,
possibly using the light for hunting but his agitated swimming suggested more
that we were intruding.
Photographs: Sail
rock, Grenadines, St Vincent.
Similar species: Shares
its Eastern Atlantic range with the West African nurse shark – Ginglymostoma
brevicaudatum
Reaction to divers: During
day lies motionless unless closely harassed. Will bite if provoked. Nurse sharks
are opportunistic and become regular visitors to shark feeds.
Diving logistics: Nurse
sharks are extremely common sights in many areas of Florida and the Caribbean.
Until recently banned, Florida shark feeding dive boats out of Fort Lauderdale
and Boca Raton, were guaranteed Nurse watching experiences. The Sea Emperor
wreck off of this same coastline usually has a group of Nurses sleeping under
the bow. More remote places in the Caribbean such as Sail Rock in the Grenadines
usually have Nurses lying under every available overhang. This dive sight is
accessible using Dive Grenadines out of Union Island.
