Sixgill Sharks Spotted in Palau’s German Channel

Our Corps of Exploration spotted these hexanchoid sharks during the H2085 dive exploring the German Channel in Palau. While most sharks today have five brachial arches or gills, these six gill sharks with an extra set are among the most primitive of all sharks. Also known as cow sharks, this deepwater species is rarely seen at shallower depths like this one at 390 meters. Sixgill sharks are ovoviviparous, meaning in their reproductive cycle eggs hatch inside the mother before being expelled in what resembles a live birth. 

This expedition, the last of ten from the 2024 season, is focused on surveying the oceanography and current flow around the Palauan Islands and how this affects both near and offshore ecosystems, including those within the Palau National Marine Sanctuary. The team includes local scientists from Palau’s Coral Reef Research Foundation and researchers from the Scripps Institution of Oceanography, along with educators, engineers, scientists, and mariners from OET’s international team. 

Learn more about the NA169 expedition, funded by NOAA Ocean Exploration via the Ocean Exploration Cooperative.