By Neil Nachbar
In the deepest, most remote parts of the ocean, there are species of sharks that have rarely been observed.
A video system developed by Brennan Phillips, University of Rhode Island assistant professor of ocean engineering, has led to the discovery of sharks in some very secluded areas.
On an expedition to an underwater volcano in the Solomon Islands in 2015, Phillips’ deep-sea camera revealed hammerheads and silky sharks living inside a crater. Known as the “Sharkcano,” Phillips’ sightings were documented in Oceanography magazine and in a video produced by National Geographic.
Having learned of Phillips’ camera work in the Solomon Islands, marine scientist Austin Gallagher asked the professor to join him and his crew on a trip to a semi-enclosed deep ocean trench in a region of the Bahamas known as the Tongue of the Ocean in May 2018. Gallagher is the chief executive officer of Beneath the Waves, a non-profit organization dedicated to the conservation of sharks and their habitats.
“There are only a few examples of these deep-drop camera systems, so I was on Austin’s radar as a potential collaborator,” said Phillips.
Using a baited remote underwater video system (BRUV) that he designed at URI, Phillips recorded the first in situ observation of a sharpnose sevengill shark in the Tongue of the Ocean.
The video system consisted two GoPro cameras attached to a carbon-fiber frame. One camera recorded 4K video, while the other recorded still images every five seconds. Two LED lights illuminated the seafloor. A small bait bag was attached to a pole to attract sharks. An acoustic-release system was used to release an expendable drop weight of 20 kilograms, enabling the system to return to the surface upon command, where it was located by GPS and retrieved.
At a depth of 718 meters, the shark circled the video system for about 10 minutes before moving on. Phillips’ work was chronicled in a video produced by Beneath the Waves.
“Brennan has an incredible wealth of knowledge and experience on ocean imaging and technology,” said Gallagher. “I really appreciate his ability to integrate engineering and exploration. He makes it easy for everyone to understand the science involved in his work.”
This month, Phillips and Gallagher will return to the Tongue of the Ocean in search of more sharks.
“The Tongue of the Ocean in the Bahamas is one of the most unique deep-water features in the subtropical Atlantic,” stated Gallagher. “It is home to many species of endemic deep-water sharks. We know from our tagging work that many surface-dwelling sharks will actually spend a fair amount of time at depths of 300-600 meters, which is incredible.”
On this trip, Gallagher will be searching for tiger sharks. His goal is to record where they are found, how they behave, and what their residency is like at various depths.
Phillips described the partnership with Gallagher as a mutually-beneficial collaboration.
“Austin wants to bring in the latest deep-sea technology to advance his research,” said Phillips. “As a result, he’s able to collect meaningful data on sharks and I get to test and refine my equipment.”
If time allows, Phillips hopes to test a newer version of the DEEPi camera he designed. The camera is compact and affordable. Encased in a 3D-printed epoxy-filled housing, the camera can be attached to baited underwater video systems, remotely operated vehicles and autonomous underwater vehicles. It can also be connected to a local network for syncing and livestream broadcast.