Flower Garden Banks – A Manta Ray Nursery

manta nursery
A diver photographs a juvenile, a denizen of the manta ray nursery at Flower Garden Banks, off the Texas coast.

MANTA RAYS ARE FOUND IN OCEANS WORLDWIDE, BUT MANTA RAY JUVENILES ARE RARELY SEEN. Except, it develops, in the newly recognized manta ray nursery in the Gulf of Mexico’s Flower Garden Banks National Marine Sanctuary.

When visiting manta specialist Josh Stewart told Flower Gardens staff he had spotted only the second juvenile he had ever seen, their response was: they see them all the time. Apparently, they assumed the smaller mantas were a different species rather than juvenile offspring of the adults oceanic manta rays (Manta birostris) that frequent the sanctuary.

Nobody realized that Flower Garden Banks was a manta ray nursery all along.

SIZE IS A KEY TO IDENTIFYING MANTA RAY JUVENILES

Adult oceanic mantas grow to “wingspans” of 10 – 23 ft/3 – 7 m. Many of the mantas found in Flower Gardens come more like 7 feet. Studying records kept over 25 years, Stewart and his Flower Gardens colleagues concluded that most of the mantas found in the sanctuary are juveniles, the complete opposite of open ocean manta populations.

Manta rays’ bodies each have distinctive patterns of spots and blotches, making it possible to identify individuals. The sanctuary maintains a catalog of dozens of known Manta birostris specimens. Stewart and his colleague from the sanctuary reported on their findings in the journal Marine Biology.

PROTECTION IMPORTANT IN THE MANTA RAY NURSERY

What factors work to make Flower Gardens’ a manta ray nursery? While adults typically move between shallow and deep waters in their pursuit of zooplankton, the smaller, more vulnerable juveniles may find that the relatively shallow habitats of the sanctuary may offer them better and safer conditions to grow in. Also, sanctuary waters are protected from commercial fishing.

For a sidebar article on Manta Ray Facts, click here.

PRINCIPAL SOURCES: Manta birostris, Florida Museum, University of Florida;  “Research raises possibility that Flower Garden Banks National Marine Sanctuary is part of manta ray nursery,” NOAA: “Nursery For Giant Manta Rays Discovered In Gulf Of Mexico,” NPR; “Rare Manta Ray Nursery Discovered,” National Geographic; “Rock-a-bye manta ray, in the ocean: The first manta ray nursery is found,” Durham Herald-Sun; “Research raises possibility that Flower Garden Banks National Marine Sanctuary is part of manta ray nursery,” NOAA; “Manta Catalog,” Flower Garden Banks National Marine Sanctuary; “Important juvenile manta ray habitat at Flower Garden Banks National Marine Sanctuary in the northwestern Gulf of Mexico,” (Abstract) Marine Biology.