White Tip Reef Shark

White Tip Reef Shark

These guys belong to a group of sharks we call requiem sharks which includes other species such as the lemon shark and blue shark. Compared to their cousins, white tips are a relatively small species reaching on average a length of 1.6m. White tips also have another difference to most of their cousins in the requiem shark family, and that is the way they breathe. The majority of requiem sharks are what are known as ram breathers or ventilators, this means that they must be swimming constantly so that water moves across their gills allowing them to breath. White tips can remain stationary on the seafloor in caves and under ledges and still breath, this is because they use buccal pumping to breath. Buccal pumping involves water being pumped through the mouth and then through the gills providing the shark with oxygen. The motion of this pumping gives the appearance that the shark is huffing and puffing after a long hard swim.

This species has quite a wide distribution and can be found in waters across the whole Indo-Pacific region. Here in Australia they can be found from the north west region of Western Australia around the north and then south to the Southern Queensland coast. Their habitat is coral reefs and they are most often found under ledges and in caves and crevices in the reef. They prefer to stay as close as possible to the bottom and can be found at depths ranging from 8 meters on the shallow coastal reefs down to 40 meters on the deeper reef slopes.

They are quite easily recognised for their small size and slender body shape. Their head shape is also quite distinct, it is short and broad not the stereotypical pointed torpedo shape and has two tubular skin flaps at each nostril. Their mouth is turned down at the corners which gives them a perpetual grumpy expression and is full of up to 50 teeth at a time. These teeth are tri-cuspid which means they have 3 points, a large centre point flanked by much smaller points. Their colouring is grey to brown with random small dark dots down their side and their dorsal and caudal (tail) fins are tipped with white, the reason for their common name.


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Like all sharks white tip reef sharks are predators, the have a nocturnal nature and are most active at night time. During the day they are quite docile sharks and can usually be found resting, sometimes in groups which is unusual for a shark as they are not generally social animals. They are so calm and docile during the day that fish are not even scared of them and will spend the day swimming around them, annoying them and even rubbing themselves up against the sharks rough skin to scratch the parasites from their scales. However as soon as the sun goes down this changes. The white tips wake up and turn into voracious little predators and will eat anything that is unlucky enough to be caught out of their hiding spot, this includes fish, crustaceans and molluscs like octopuses.

Even though they are fearsome little predators the white tip reef shark is not considered particularly dangerous to humans and will rarely show aggression towards us. All recorded attacks from this species were considered provoked, usually spear fisherman getting a nip while the shark was trying to snack on their catch or people who had been attempting to hand feed them. The sad part is that these little sharks are listed as near threatened by the IUCN. This classification is the direct result of human interference and activity. We don’t like to eat them as they are considered toxic due to ciguatera contamination, a result of the sharks diet, so they aren’t considered to be overfished. However as our human industries spread over and into the world's oceans, the coral reef habitats of these sharks are dwindling, which causes the same thing to happen to their numbers. As they are quite slow to reproduce and have small litter sizes it is quite difficult for this species to bounce back after a population decline.