Baby shark enchants researchers

December 6, 2018 Catshark embryo filmed in the Caribbean

From October 30 to November 20, 2018, NOAA and its partners conducted an expedition with the research vessel "Okeanos Explorer". The expedition took place in Puerto Rico and the U.S. Virgin Islands to explore the deep sea in these areas of the Caribbean.

One of the most impressive observations the researchers made with the aid of the autonomous UW vehicle "ROV Deep Discoverer" is a lively catfish embryo in its egg case. The images show the embryo with yolk sac that moves - swimming movements to pump fresh water through the permeable walls of the egg case.

Cat sharks lay fertilized eggs that are attached to algae or invertebrates by means of long threads at their four corners. A yolk sac inside the egg capsule supplies the embryo with the necessary nutrients for its development. After a few months, the little shark hatches, is able to swim and can feed itself.