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62 st / February 2016 www.sea-technology.com SharkCam Gathers Data On Sharks in the Deep The dramatic video footage of a great white shark attacking the "RE- MUS SharkCam" AUV brought some of the highest ratings to Discovery Channel's "Shark Week" 2014 and went viral on the Internet. But while the footage was unprec- edented, the scientifc understanding enabled by the REMUS SharkCam is just as groundbreaking. The AUV was used during a science expedition in 2013 to better understand white shark behavior and represents the frst suc- cessful efforts to autonomously track and image any animal in the marine environment. The research provides critical data for efforts to conserve these animals. Working in the clear waters off Mexico's Guadalupe Island, re- searchers conducted six AUV mis- sions over seven days in November 2013. The team tagged and tracked four sharks over six days using RE- MUS SharkCam, collecting over 13 hr. of video data from the AUV. The team tracked one male and three female great white sharks down to depths of 100 m. Most of the encounters REMUS SharkCam documented were with animals that were not being tracked. The researchers logged 30 interac- tions with 10 individual sharks. The behavior of these sharks flmed by REMUS SharkCam ranged from sim- ple approaches to bumping the ve- hicle and aggressive bites. The observations made by the team constitute the frst observations of predatory behavior well below the surface. The fndings suggest the sharks take advantage of the clear visibility in the waters off Guadalupe to search for seals and to ambush and disable them by attacking from be- low, where the shark is concealed in darker water while stalking the seal, which is silhouetted from above. The team recently returned to Guadalupe to continue tagging, flm- ing and studying great white sharks. The new video will be released in summer 2016 during Discovery Channel's "Shark Week". In the future, the team wants to use a deeper diving REMUS that can swim for longer durations. Future work will center on increasing track- ing durations by using better batteries and integrating the camera systems into the AUV electronics. The SharkCam offers an innovative tool for scientists to better understand the fne-scale behavior of marine animals. There is currently no other method in the world that can get im- agery of white sharks at depth in the open ocean. New Hydrothermal Vent Type Discovered The frst discovery of a new type of hydrothermal vent system in a decade helps explain the long observed dis- connect between the theoretical rate at which the Earth's crust is cooling at seafoor spreading ridge fanks and actual observations. It could also help scientists interpret the evidence for past global climates more accurately. This discovery was made by scien- tists at the U.K. National Oceanogra- ocean research