Common Names for Whitetip Reef Sharks around the World English
language common names include whitetip reef shark, blunthead shark,
blunt-head shark, light-tip shark, reef whitetip, reef whitetip
shark, white tip reef shark, white-tip reef shark, whitetip shark,
and white-tip shark. Common names in other languages include
aileron blanc de lagon (French), arava (Tuamotuan), cazn (Spanish),
cazn coralero trompacorta (Spanish), daaha (Somali), endormi requin
(French), eno-eno (Gela), faana miyaru (Maldivian), gursh (Arabic),
ikan yu (Malay) libaax (Somali), maog (Niuean), malu (Samoan),
mamaru (Tahitian), man ll kea (Hawaiian), marracho de covas
(Portuguese)
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Where Whitetip Reef Sharks are found in the World
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Geographical Distribution The whitetip reef shark has a wide
range in the Pacific Ocean, including South Africa and the Red Sea
to Pakistan, Sri Lanka, Burma, Indonesia, Viet Nam, Taiwan, Riu Kiu
Islands, Philippines, Australia and New Guinea. It is common in
Polynesia, Melanesia, and Micronesia, northward to the Hawaiian
Islands, and southwest to the Pitcairns. In the eastern Pacific,
the whitetip reef shark lives in waters off the Cocos and Galapagos
Islands, and Panama north to Costa Rica. It is one of the most
common reef sharks in the Pacific Ocean, along with the blacktip
reef shark (Carcharhinus melanopterus) and the grey reef shark
(Carcharhinus amblyrhynchos).
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Habitat The whitetip reef shark typically lives along the
bottom in clear, shallow waters surrounding coral reefs. It has
been reported at depths to 1,083 feet (330 m). Rarely coming to the
surface, this shark is capable of lying motionless on the bottom
substrate for long periods of time. During daylight hours, whitetip
reef sharks form aggregations in caves, sometimes appearing stacked
up like a pile of logs. The same sharks often return repeatedly to
the same cave for long periods of time, changing location only
periodically. The whitetip reef shark is most active throughout the
night. Site fidelity is strong with each shark maintaining a small
home range for months or years at a time.
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Coloration The whitetip reef shark earns its common name for
the distinct white tips on the first dorsal and upper caudal fins.
The body is dark gray to brownish, fading to a light ventral
surface. Small dark spots may be present over the entire body. The
remaining fins may also have white tips, however this may not
always hold true.
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Size, Age, and Growth The whitetip reef shark grow to a maximum
length of just under 7 feet (2.13 m), however individuals are rare
at lengths over 1.6 m (5.25 feet). Males mature at about 3.4 feet
(1.05 m) and generally reach 5.5 feet (1.68 m) in length. Females
reach maturity at 3.4- 3.57 feet (1.05-1.09 m) and grow to at least
5.18 feet (1.58 m). This species is known to reach a maximum age of
at least 25 years.
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Physical Anatomy
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The whitetip reef shark feeds during the night on benthic
prey.
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Foods for whitetips sharks. This shark is a specialist in
capturing bottom-dwelling prey in caves and crevices, feeding
primarily on octopus, lobsters and crabs. It also feeds on bony
fishes including eels, squirrelfishes, snappers, damselfishes,
parrotfishes, surgeonfishes, and triggerfishes. During the night,
this shark becomes very active, searching for prey items along the
bottom substrate. When a prey item is located, the shark will
pursue it into a crevice and jam itself in after it. The tough
skin, slender build, blunt snout, and protective eye ridges make it
possible for the whitetip reef shark to hunt successfully within
these very small spaces.
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Predators Predators of the whitetip reef shark include large
piscivorous fishes such as the tiger shark (Galeocerdo cuvier) and
giant grouper (Epinephelus lanceolatus).
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Tiger Shark
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Importance to Humans The whitetip reef shark is fished in the
waters off Pakistan, India, Sri Lanka, and Madagascar. Although
data on the commercial fishery involving this shark are lacking, it
is also probably fished in other waters throughout its range. It is
caught with floating and bottom gillnets and longlines. The liver
and flesh is marketed for human consumption, although it has been
reported to cause ciguatera poisoning.
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Danger to Humans This shark is relatively harmless to humans
due to its easygoing disposition and small teeth. It avoids close
contact with humans, swimming off when approached by swimmers and
divers. Often attracted to food, divers have been able to hand feed
individual whitetip reef sharks. However, on occasion, a shark will
become overly excited by spearfishing or when bait is present,
resulting in a bite to a diver. This species is also known to bite
if harassed. In Hawaii, some families regarded this shark as
'aumakua', a guardian spirit. They would feed rather than hunt
whitetip reef sharks.
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Conservation The whitetip reef shark is currently listed by the
World Conservation Union (IUCN) as "Near Threatened" at this time.
The IUCN is a global union of states, governmental agencies, and
non- governmental organizations in a partnership that assesses the
conservation status of species. Due to restricted habitat and depth
range as well as small litter size and late age at maturity, this
shark may become threatened with increasing fishing pressure.
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Scientific Article Encountered by divers, very little has been
written other than distributional records. The purpose of this
paper is to review what is known of the biology of this shark and
to present some original data on its life history. These data were
assembled incidentally to other projects, as the opportunity arose,
beginning December 1966. CLASSIFICATION Carcharias obesus was
described by Rtippel1 (1835: 64, pI. 18, fig. 2) from a specimen
from Jeddah, Red Sea. The choice of the specific name is
unfortunate, for obesus is a slender species. Klausewitz (1960:
291, pI. 42, fig. I, text-fig. 4) illustrated the holotype and its
teeth; it is housed at the Senckenberg Museum, Frankfurt, under
number 3149. Miller and Henle (1837) proposed the genus Triaenodon,
selecting obesus as the type species of the genus. Until recently
most authors, including Bigelow and Schroeder (1948), have placed
Triaenodon in the Triakidae.