Fascinating new research has found that young Caribbean manta rays (Mobula yarae) frequently travel with groups of other fish – forming small, moving ecosystems that support a range of marine life.

Researchers from the University of Miami Rosenstiel School of Marine, Atmospheric, and Earth Science, in collaboration with the Marine Megafauna Foundation found that South Florida – particularly the waters off Palm Beach County – functions as an important nursery ground for juvenile manta rays.

For nearly a decade, scientists with the Marine Megafauna Foundation have monitored these young rays, documenting the growing pressures they face from coastal human activity, including boat strikes and entanglement in fishing gear.

“Using video footage collected between 2016 and 2021, we analysed 465 videos to better understand which species swim with manta rays and how they interact,” said Emily Yeager, lead author of the study and a doctoral candidate in the Department of Environmental Science and Policy at the Rosenstiel School. “We looked at which fish were present, how many there were, and where they tended to gather – often around the manta’s gills, eyes, wings, and tail.”

The analysis showed that four families of teleost fish – the largest group of ray-finned fishes – regularly associate with juvenile mantas. The most common companions were remoras, or suckerfish, known for attaching themselves to larger animals using a suction-like dorsal fin. Other frequent associates included jacks and cobia, species that also play an important role in Florida’s commercial and recreational fisheries.

“Understanding ecological interactions between species is essential to conserving the marine environment,” said Catherine Macdonald, an associate professor in the Department of Environmental Science and Policy and director of the Shark Research and Conservation Program at the Rosenstiel School. “Our results suggest that these species may be interdependent and form long-lasting and relatively stable relationships, creating mobile ecosystems where fish may mature, feed, or mate.”

The findings carry particular weight in South Florida, a region heavily used for boating and recreational fishing. Juvenile manta rays often swim near the surface, making them especially vulnerable to vessel strikes and fishing gear, along with the fish communities that accompany them.

“Slowing down in areas where mantas are known to feed near the surface is a simple but crucial step toward protecting these young rays,” said Jessica Pate of the Marine Megafauna Foundation, a co-author of the study. “Responsible boating and fishing can help protect these species and their critical ecological interactions long-term.”

“The findings provide valuable insights for marine conservation and policy, showing that manta rays act as living habitats that support biodiversity in coastal waters.” Yeager added.

The research was supported by the University of Miami’s Maytag Fellowship and a Florida Sea Grant–Guy Harvey Fellowship held by Ph.D. candidate Emily Yeager.

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