For many divers, their first glimpse of a shark will be a whitetip reef shark. Not to be mistaken for oceanic whitetips, whitetip reef sharks can often be seen resting on the seabed during the day and offer little, if any, threat to humans. As one of the most common sharks found on dive sites throughout the Indo-Pacific, knowing where they like to hang out and how to identify them will come in handy on your next dive trip. So, without further ado, here's our top ten whitetip reef shark facts.
1. Whitetip Sharks: Oceanic or Reef?
Whitetip reef sharks are commonly called 'whitetips,' but in some locations, such as the Red Sea, divers may also encounter the oceanic whitetip shark. While both species have a white-tipped fin, they are remarkably different. Physically, whitetip reef sharks are smaller and somewhat cigar-shaped, while oceanic whitetips are bigger and bulkier. As one of the ocean's top predators, oceanic whitetips also prefer to spend their time out in the blue, while whitetip reef sharks tend to stick to reefs.
2. How to Identify Whitetip Reef Sharks
Whitetips have a 'fishier' appearance than most sharks. These slender sharks seldom reach two metres in length and tip the scales at 22 pounds, which is the same average size as a king salmon. True to their name, they have white tips on their first dorsal and caudal fins. The first dorsal fin also sits quite far back on the body, behind the rear margin of its pectoral fins. If you catch these docile sharks swimming, you'll notice the upper body is grey which fades to a light underbelly below.
3. They Can Rest on The Bottom
Similar to other shark species, whitetip reef sharks use ram ventilation - swimming to propel water through their gills - to breathe. However, whitetips can also breathe by buccal pumping, whereby the shark will drop its lower jaw to suck water into its mouth and over its gills. This allows them the luxury of resting on the ocean floor throughout the day. So, if you see a whitetip shark lying motionless with its mouth wide open, don't fret, it's still breathing.
4. Whitetips Are Night Owls
Whitetips are nocturnal hunters and prey on the fact that many of their favourite meals (like octopuses, fish and crustaceans) will be caught off guard or asleep.
This nocturnal lifestyle means the sharks need to rest during the day, which is why you can often see them stationary on sandy patches or snoozing under overhangs.
5. How Do They Find Prey in The Dark?
While whitetips can detect movement, they don't have full night vision. To combat this, they use an array of senses - like smell and hearing - to find their favourite prey. Alongside other sharks and rays, whitetips are also blessed with a series of electroreceptors in their snouts, known as the ampullae of Lorenzini. These receptors allow sharks to detect electromagnetic impulses, such as those emitted by a fish's heartbeat.
6. Where to Dive with Whitetip Reef Sharks
Whitetip reef sharks can be found on shallow reefs across the entire Indo-Pacific, from Tanzania and Mozambique on the east coast of Africa, to Cocos Island and the Galapagos Islands off the west coast of Africa. In the Revillagigedo Archipelago - commonly known as Socorro - in Mexico, it's not uncommon to see piles of whitetip reef sharks resting on top of each other in the caves and ledges of Roca Partida.
7. Favourite Hangouts
During the day, you'll often spot these sluggish sharks taking a kip on quiet sandy patches, caves and overhangs. Whitetips are a social bunch and can often be seen resting in groups, especially in cave areas, such as Gato Island in Malapascua and Siaes Tunnel in Palau.
On dive sites with deep walls, such as Blue Corner in Palau, whitetips are often seen cruising up and down the reef's edge, where the strong currents can sometimes push unsuspecting prey up the steep walls.
8. Whitetip Reproduction
As with other members of the Carcharhinidae family of sharks, whitetip sharks are viviparous, meaning their young develop inside the female before being born live. If you're lucky enough to plan your trip to coincide with whitetip mating season, you will notice trains of white tips, with the female being followed nose-to-tail by five or six males. When a male successfully grabs a female's pectoral fin, the pair will slowly sink to the bottom, where copulation and fertilisation will hopefully occur.
9. They’re Guardian Spirits
In Hawaiian mythology, an 'aumakua is a personal or family guardian spirit, and these can take the form of an owl, bird, octopus or even a whitetip shark. Hawaiian-born actor Jason Momoa, also known as Aquaman, has a tribal shark-tooth pattern tattooed on his left forearm that is a tribute to his family's 'aumakua, which is a shark.
10. Whitetip Conservation Status
The most dangerous predator of the whitetip reef shark is, unfortunately, humans. The IUCN has listed whitetips as 'Near Threatened' on its Red List of Threatened Species. They are fished commercially for tropical markets, while their shallow dwellings also make them susceptible to becoming bycatch. In the ocean, they are also preyed upon by larger sharks, such as the tiger shark (Galeocerdo cuvier) and silvertip shark (Carcharhinus albimarginatus).