Last update: January 19th, 2020 at 8:00 am
A deep sea ray and sea whip coral as observed from Alvin, an active predator of the deep sea, not uncommon we believe, but the encounter of the ray with Alvin was not common for us, and quite exciting. In this photo is also a deep sea coral, a sea whip, of the Order Gorgonacea. Deep sea corals are unique creatures, related to those that inhabit and populate tropical coral reefs, though these live in a world without light.
Also deep sea ray and sea whip coral are found in warm temperate, subtropical and tropical waters. Both species are pelagic; M. birostris migrates across open oceans, singly or in groups, while M. alfredi tends to be resident and coastal. They are filter feeders and eat large quantities of zooplankton, which they gather with their open mouths as they swim. Gestation lasts over a year, and mantas give birth to live pups.
Both species are listed as vulnerable by the International Union for Conservation of Nature. Anthropogenic threats include pollution, entanglement in fishing nets, and direct harvesting for their gill rakers for use in Chinese medicine. Their slow reproductive rate exacerbates these threats.
A deep sea ray and sea whip coral as observed from Alvin are protected in international waters by the Convention on Migratory Species of Wild Animals, but are more vulnerable closer to shore. Areas where mantas congregate are popular with tourists. Only a few public aquariums are large enough to house them.