DISCOVERY IN GREAT WHITE SHARK BEHAVIOUR
Most of what was known about Great White Sharks was limited to information received from electronic tagging and direct observation. That all changed when an automated unmanned vehicle (AUV) was utilised to swim amongst, and study, these magnificent creatures.
According to the Woods Hole Oceanographic Institution, the drone (named REMUS) picks up special acoustic tags which allow it to track and follow sharks. It is equipped with 6 cameras, giving scientists a panoramic as well as a rear view.
Marine biologists had a chance to witness the predatory behaviour of Great White Sharks first-hand as the drone was attacked nine times during the thirteen hours of footage. Amongst the sharks observed was Deep Blue, a massive shark with a length between 6 and 7 metres – possibly the biggest Great White Shark ever observed.
The drone became unexpected bait several times, finding itself between the jaws of these mighty beasts, although not all the sharks attacked the drone. Some of the great white sharks merely swam up to the AUV to inspect, bump and nudge it, showing territorial behaviour.
The sharks use depth to their advantage as they ambush their prey from the darkness. Their victims swim unknowingly above; their silhouette giving away their position as the shark lurks in the pitch black depths, locking onto its target.
This predatory behaviour was previously only a subject of speculation without any hard evidence. Now there is proof of how the shark uses light to hunt. It is believed that Great White Sharks dive down almost 200m to get their advantage.
Although we have been given some interesting insights into the Great White Sharks’ predatory behaviour, things such as their social lives and where they reproduce are still relatively unknown. One of the big reasons for this has been the lack of close observation after they disappear into the depths of the ocean.
This drone technology could help us answer some of the basic questions about this predator. Not only that, it can also be used to study a range of things from marine life to conservation of the oceans. REMUS allows us a spectacular view into sea life.
The king of the ocean has been an elusive predator, but now these drones have allowed us to dive deeper into the mysterious world of the Great White Shark.