'MONSTER' SHARK BIGGER THAN A SUBMARINE FILMED BY SCIENTISTS AS IT TRIES TO EAT THEIR GUN
team of researchers has captured incredible footage of a close encounter with an ancient species of shark known as the bluntnose sixgill.
The team, led by Dean Grubbs, from Florida State University, were conducting dives in a submersible called "Nadir" as part of an expedition organized by OceanX to tag one of the sharks in their deep-sea environment.
During one of the dives, the team were fortunate to come up close and personal with a huge female bluntnose—=one of the largest sharks in the world—which one of the researchers in the video can be heard describing as "definitely bigger than the sub is long."
The sub crew were left in a state of awe by the encounter: "My goodness that is amazing," one of the team comments, while another can be heard saying, "This is a monster. She is huge." At one point the shark even tries to nibble on the spear gun attached to Nadir.
The bluntnose (Hexanchus griseus) is part of an old lineage of sharks that can be traced back 180 million years in the fossil record. In fact, it represents perhaps the oldest living lineage of sharks in the world, the researchers say. They are highly distinctive due to the fact that they have six large conspicuous gill slits, hence the name. Most sharks only have five.
"They have a single dorsal fin that is placed far back on the midline near the tail," Gavin Naylor, one of the scientists on the expedition from the Florida Program for Shark Research at the Florida Museum of Natural History, told Newsweek. "They are reported to grow to over 5 meters [16 feet] long and weigh more than a ton. They are live bearing. Females can have over 80 pups in a litter. They are likely primarily carrion feeders, but may also take live prey when the opportunity arises. Females are larger than males."
Bluntnose sixgills are distributed across tropical and temperate waters around the world usually living at depths of between 650 and 3,300 feet, although they have been spotted up to 5,000 feet below the surface. However, researchers know very little about this mysterious species. Tagging them could enable scientists to learn more about their biology and behavior, and protect them from threats.
"Approximately half of all living species of sharks on the planet live their entire lives in the deep sea," Grubbs told Newsweek. "Yet we know virtually nothing about their biology and ecology. Contrast this with the volumes of scientific information on species like white sharks and tiger sharks. Yet as commercial fisheries globally move deeper, deep sea sharks are being increasingly caught, particularly as bycatch."
"It is often assumed that these deep sea sharks would die if released," he said. "We began this project in 2005 to begin investigating whether deep sea sharks caught and brought to the surface survive if released. Since this time we have tagged more than 20 bluntnose sixgill sharks with archiving satellite tags and another 50 with simple identification tags. But all of these were tagged by bringing the sharks to the surface and tagging them alongside the boat or even bringing them onto the deck of ship."
