The whitetip reef shark is relatively small, reaching average lengths of about 1.6 meters (5.2 feet).  The heaviest recorded whitetip reef shark was 18.3 kilograms (40 pounds). While large for this species, it still is not nearly as big as the majority of other sharks.

Triaenodon obesus has a thin body with a short head and flattened snout, evolved over time to be able to better reach into crevices in the rock for prey. According to the study “Contribution to the Biology of the Whitetip Reef Shark” (performed by John E. Randall, 1977), these sharks also have 43 to 50 teeth in each jaw, in two rows. It is also “closely associated with coral reefs and is often seen at rest in caves.” (Randall 143)

Their skin is also very smooth, also in order to reach higher swimming speeds when chasing after prey, as well as more ease of entry when sliding through gaps in the rock after those same animals. Whitetip reef sharks possess structures called dermal denticles, or non-growing, flexible scales the coat the body. It is these denticles that allow the sharks to have such smooth skin, since they have about 7 horizontal ridges and are very small, allowing much overlap between them.

The whitetip reef shark has oval-shaped eyes with vertical pupils, very much like a cat’s eye. This is, according to the study “Comparative visual function in elasmobranchs: Spatial arrangement and ecological correlates of photoreceptor and ganglion cell distributions” (performed by Lenore Litherland and Shaun P. Collin, 2008), a specific evolution to allow the sharks to see better at night, when there is not much light to rely on. The slit pupils allow the remaining light to be focused inside of the eye, giving the shark a clearer picture of what is going on. Their eyes have reflective plates passing light back through the retina a second time.

Triaenodon obesus also has a very acute sense of smell. Like most sharks, this sense is extremely well-developed, far beyond anything a human could achieve. They have the ability to detect small scent particles carried to them by ocean currents. Whitetip reef sharks could smell even a few drops of liquefied tuna in an area the size of an average  swimming pool.

Unlike many sharks, Triaenodon obesus does not need to keep swimming in order to stay alive. In reality, they spend many of the daylight hours sitting on the bottom of the reef. The whitetip reef shark has the ability to move water over its gills as they lie at the reef floor, staying still for periods of hours at a time. This is both to conserve energy for hunting later, as well as a method to camouflage themselves from potential prey.

Perhaps the most obvious identifying factor of the whitetip reef shark are the white tips on its fins. Other than those white tips, these sharks follow a fairly standard coloration, being gray on the ventral side and white on the dorsal end. This is for camouflage purposes as well, to ensure animals looking from above will only see the dark ocean, and from below, the bright sunlight.

Home Nutrition