Gray Reef Shark
The Grey Reef Shark is also known
as black-vee whaler, gray shark, gray whaler shark, longnose blacktail
- GRAY REEF SHARK
Scientific Name.... Carcharhinus Amblyrhynchos
gray reef shark is gray in color and has a moderately long, broadly
rounded snout, eyes usually rounded, they have no interdorsal ridge,
large second dorsal fin with short rear tip. Pectoral fins are
narrow and falcate.
maximum size of the gray reef shark is approximately 8.3 feet long,
but the average size is 5.8 feet. Females mature at 49-55 inches,
while males mature at 48 to 57 inches.
have narrow triangular, serrated upper teeth.
gray reef sharks are gray above , and white below. First dorsal is
plain or irregularly to prominently white-edged, obvious broad black
posterior margin to entire caudal fin, blackish tips to other fins.
These sharks feed on small bony fishes such as needlefishes,
butterflyfishes, morays, squirrelfishes, scorpionfishes,
surgeonfishes, parrotfishes. There diet also includes squids,
octopuses, and crustaceans, lobster and shrimps. Studies suggest
that the gray reef shark feeds more on bottom-dwelling marine life,
than mid-water species. Groups of these sharks have been observed
herding schooling fish up against the reef before attacking them.
They will also follow jacks and will scavenge on the leftovers
resulting from the jack feeding events.
Gray reef sharks are a social species, aggregating by day in or near
reef passes or lagoons. Often cruises near bottom but will visit
surface to investigate food sources and venture several km offshore
before returning to home site. Even more active at night, when
groups disperse. Inquisitive, several sharks may approach divers
closely in seldom-dived areas, but soon disperse and seldom reappear
except at a distance during repeated dives. They display an
intimidating threat by by their exaggerating swimming pattern with
head and tail wagging in broad sweeps, back arching, head lifting,
pectoral fin lowering and sometimes horizontal spiral swimming is
performed if approached too closely or startled, unless food is
present. Display varies from almost immediate flight, to a series of
figure-eight loops to biting then fleeing. Gray reef sharks are
inquisitive and is attracted to the low-frequency underwater sounds
and commotion caused by a speared fish, with many stories of a gray
reef shark taking a fish off the end of an unsuspecting
spear fisher's spear.
are found in Central Pacific to Madagascar and occurs at depths of
3.4 to 905 feet. They inhabit near coral reefs, where it occurs in
lagoons, on the reef face and fore reef slope. It is most abundant
on outer reef slopes, and at the entrances of reef passes. In some
regions this species is more common around low, coral islands and
atolls, rather than around high islands, and is reported to be more
common on the leeward side of these islands. It is less likely to be
present in shallow, intertidal habitats in regions where it
co-occurs with the blacktop reef shark an apparent competitor. The
young favour shallower water than adults.
longevity is believed to be around 25 years.
sharks are viviparous, yolk-sac placenta, and give birth to 1 to 6
pups. The gestation period is 10-12 months, and females breed
biannually. Pups measure about 20 to 24 inches at birth and reach
maturity after about 7 years.
are very active strong swimmers.
attacked if threatened. These sharks have severely bitten and
injured divers, to threaten them, not to eat them. They should be
treated with respect, although most dive encounters with it are
According to IUCN List ( International Union for Conservation of
Nature and Natural Resouces ) they are near threatened. Formerly
common in clear tropical coastal waters and oceanic atolls, now
under threat because of restricted inshore habitat, site fidelity,
small litter size, relatively late age of maturity and increasing
unmanaged fishing pressure. More valuable protected for dive tourism
than for fisheries.