Subject:
A Whitetip Reef Shark (Triaenodon obesus) patrols a Balinese reef in the Lombok Strait. Thanks to their wide geographical range, Whitetip Reef Sharks are among the most common shark species on the Indo-Pacific coral reefs. They are probably the most encountered shark species by scuba divers.
Although the Whitetip Reef Shark's maximum length in reference books is 210cm/6.9ft, their actual size rarely exceeds 160cm/5.2ft. The average weight of this shark is between 15kg/33lb. and 20kg/44lb.. They are easily recognised by their slender, grey-coloured body and the white stripe on top of their first dorsal and upper caudal fin.
The Whitetip Reef Shark is a nocturnal hunter, and during daylight hours, they are often found resting on the bottom and in small caverns and overhangs. At night, the Whitetip Reef Shark becomes active and patrols the tropical reefs and coastal waters of the Indo-Pacific for food. They feed on a wide variety of bottom-dwelling fish species, as well as crustaceans like crabs and lobsters, and some mollusk species, mainly octopus. Their slender body is well adapted to squeeze in-between coral heads and can easily enter small openings in caves and caverns. They often find their food in those places on the reef that are inaccessible to other requiem sharks (Carcharhinidae) species.
The Whitetip Reef Shark hunts primarily using their smell and hearing capacities. Wounded and injured fish produce low-frequency sounds (25–100 Hz) to which the Whitetip Reef Shark reacts.
Unlike many shark species, it does not need to constantly swim in order to breathe. The Whitetip Reef Shark has the ability to pump water across its gills without having to move forward. Therefore, these sharks are often encountered lying on a sandy bottom. Although non-territorial, they are quite attached to a particular cave or coral reef. They might easily spend most of their lives in the same area.
Technique:
A strategically placed GoPro can be a great aid in underwater filmmaking. More than ten years ago, we observed a Whitetip Reef Shark on a Balinese reef in the Lombok Strait, the body of water that separates Bali from Lombok. We noticed that the shark swam the same pattern over and over again. So we decided to position the little action camera where we were sure the shark would swim by. We positioned ourselves about 15m/50ft away from the camera to be sure that the action camera didn't capture us in the scene. The GoPro we had at that period in time was one of the very first models on the market and lacking a screen on the back. Placing this little underwater camera in the right position wasn’t that easy and a little luck was welcome. However, with luck on our side this move paid off and resulted in a very close encounter, at least for the camera, with a beautiful predator and some very nice underwater video footage.
We almost never use our GoPro camera, but sometimes, and in a few rare cases, it is a great tool that can deliver that special shot too difficult to obtain with most handheld underwater cameras. By observing marine wildlife, the underwater videographer might be able to predict swim patterns and anticipate animal behaviour, making filming underwater creatures a little easier.
This shot was used in our multiple award-winning documentary “The Indonesian Throughflow” (https://www.youtube.com/watch?v=zqAuJPzop3Q).
Join us on a journey of discovery and entertainment as we explore fascinating marine wildlife topics and explore the many exciting underwater adventures on our YouTube channel and our Facebook page!
Also you can capture the magic of the underwater world with our online Marine Wildlife Videography course!