Recently, we saw a video of a manta ray, that had dived to a depth of 560 ft. A spectacular sight, this eerie white creature in the dark, deep water, accompanied by a school of tiny fishes. But how deep can a manta ray dive?
Research has shown that manta rays do not swim, but glide down. Gliding is more efficient than swimming. Pop-up satellite archival transmitting tags on nine reef manta rays, Manta alfredi, were used to determine diving behaviors and vertical habitat use. Transmitted and archived data were obtained from seven tagged mantas over deployment periods of 102–188 days, including three recovered tags containing 2,6 million depth, temperature, and light level data points collected every 10 or 15 seconds. Mantas frequented the upper 10 m during daylight hours and tended to go to deeper water throughout the night. Six of the seven individuals performed a cumulative 76 deep dives (>150 m) with one individual even reaching 432 m. This ray species therefore uses several water layers.
More info in the full article in PlosOne:
Diving Behavior of the Reef Manta Ray Links Coral Reefs with Adjacent Deep Pelagic Habitats, by Camrin D. Braun, Gregory B. Skomal, Simon R. Thorrold, Michael L. Berumen
http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0088170
See a manta dive do a depth of 560 feet: