The White Reef Shark is desribed as a bottom shark and classified as a Requiem Shark. It occupies a wide range of habitats and has a remarkably wide range of distribution. Considered an unaggressive shark, it is commonly the first shark encountered by a new diver.
One of the most often seen and photographed sharks in the Pacific region is the Whitetip Reef Shark – a small, slender shark that is generally indifferent to divers. Because of its wide distribution and great abundance, the Whitetip Reef is often the first shark encountered by a new a diver and, while it may not be large or threatening, it is still a thrill to see.
The Whitetip Reef is often described as a bottom shark – the type of shark that spends a good deal of the day resting on the bottom. It is capable of pumping seawater through its gills and does not need to swim in order to breathe.
Although this shark is classified as a Requiem Shark, it does not resemble any of the classic members, such as the Gray Reef, Silvertip, Caribbean Reef or Oceanic Whitetip.
The Whitetip Reef Shark’s scientific name is Triaenodon obesus. It has no near relatives and does not seem to be part of a group in its genus. It is small in comparison to other sharks encountered on the coral reef. It generally ranges in size from three and a half to five and a half feet. The largest ever caught measured seven feet but this is quite rare.
The Whitetip can vary considerably in color and sometimes in pattern. Most of these sharks have a basic body color that is either darkish gray or slightly brown on the top and sides. The body coloration fades to white on the underside. Occasionally, a Whitetip Reef Shark will have a few dark spots or blotches randomly spaced along the top or sides of its body.
The Whitetip has a fairly distinctive body and head shape and has white fin tips. The body is generally slender and this animal often swims with an almost snake-like motion. The Whitetip’s head is flattened, with a blunt snout and very conspicuous nasal flaps on the underside. At first glance, these flaps look like barbells. The mouth of this shark is forward of the eyes, similar to that of the Nurse Shark.
The fins of the Whitetip Reef Shark are perhaps one of the best ways to identify this species. All of the fin tips are pointed. There is a conspicuous white tip on the first dorsal fin as well as the upper lobe of the caudal fin (tail). The rest of the fins are the same color as the shark’s body. This shark is quite distinctive in appearance and is rarely confused with other sharks. It has no close look-alikes.
The Whitetip Reef Shark has a remarkably wide range of distribution. It can be found throughout the tropical waters of the Pacific, extending from Central America all the way to Australia. Its range extends into the western region of the Indian Ocean as well. This shark species is very common in such areas as Cocos Island, the Galapagos Islands, Hawaii, Micronesia, Fiji, Papua New Guinea and Australia.
The Whitetip Reef Shark inhabits the shallow regions of coral reefs, lagoon areas and the outer faces of drop-offs. It can be found at a wide range of depths from 10 to 130 feet. It has even been observed by submersibles at 700 feet.
The Whitetip occupies a wide range of habitats. It is often found lying on the bottom of channels or passes that lead from the open sea to shallow lagoons. Whitetips are also found lying in coral caves, under coral ledges, in sand gullies, between rocks and in shallow lagoons.
If a Whitetip Reef Shark has taken up residence in a coral cave, it is likely to return to this same cave every day – sometimes for years. In Hawaii, these sharks often occupy lava tubes or caves. At Cocos Island, the same species of shark can be found lying around the base of huge boulders and sometimes under these rocks.
The Whitetip Reef Shark exhibits distinctively different behavior night and day. During daylight hours, Whitetips often lie on the bottom in small groups – clustered close together. At night, the same sharks become active, split up and hunt for food on an individual basis.
In areas where Whitetip Reef Sharks occupy channels or coral passes, they are often affected by tidal rhythm as well as darkness. They become active and hunt for food during slack water periods and then resume resting on the bottom when the current picks up.
Whether feeding at night or during slack tide, the Whitetip Reef Shark is basically a bottom feeder. It spends most of its time hunting in the cracks and crevices of the coral reef for small fish, octopus, crabs, lobsters and other crustaceans. This species is exceptionally tenacious about digging its prey out of a coral crevice or hole by forcing its head into small places.
The Whitetip Reef Shark is considered an unaggressive shark. It is neither attracted nor frightened by scuba divers and will actually let them approach within 10 feet before it begins to move away.
Should you encounter a sleeping Whitetip inside a small cave, do not block the entrance or its escape route. Preventing the shark from departing can cause it to panic and begin bouncing off the cave walls and thrashing the bottom. The ensuing chaos and decreased visibility could result in an accidental bite.
Divers should not attempt to sneak up behind a Whitetip Reef Shark that is sleeping or resting on the bottom and yank on its tail. Such actions could result in a bite. The slender, sinewy body of the Whitetip is remarkably flexible and can bend in almost a horseshoe shape – snapping at its tormentor.
The Whitetip Reef Shark is surprisingly intelligent and quickly develops a response to new stimulus. Needless to say, the availability of food is one of its strongest stimuli. If spearfishing is conducted in a specific area of the coral reef on a frequent basis, the Whitetip Reef Shark will soon associate the sounds with a potentially easy meal. The noise of firing spearguns is quickly linked with the vibrations of wounded fish – easy prey for a speedy Whitetip. It isn’t long before the noise of the outboard engine or the first firing of the speargun brings the Whitetip Reef Shark out of its cave.
As with most sharks, the Whitetip’s behavior is drastically altered by spearfishing activity. It will become aggressive in its attempts to grab the speared fish before the diver can reel it in. Most Whitetip bites are accidental and associated with the confusion and mayhem that occurs during spearfishing activity.