Tagging Sharks to Study the Twilight Zone

Former WHOI Joint Program graduate student and current University of Washington postdoc Camrin Braun and his team on the charter fishing vessel Machaca managed to tag two porbeagles, a relative of the goblin shark, about 30 miles east of Chatham, Mass. One was a female nearly seven feet long and weighing 270 pounds. A male came alongside the boat while the team was tagging her and, when they were finished, they quickly hooked the curious male, which measured 6.5 feet and weighed 230 pounds. Both fish are now equipped with fin-mounted SPOT satellite tags, which will report their location each time they surface and can last up to five years. For the Ocean Twilight Zone team, the big predators are an important indicator of where mesopelagic animals are collecting deep below the surface. In short, the predator will go where the prey is.