Scientists have discovered a site off the Texas coast that they say is the world’s first known manta ray nursery.
Joshua Stewart, a marine biology graduate student at Scripps Institution of Oceanography at the University of California San Diego, worked with experts from NOAA’s Office of National Marine Sanctuaries to make the remarkable find.
The oceanic manta ray nursery is located at Flower Garden Banks National Marine Sanctuary, and is the first of its kind to be described in a scientific study, according to a statement released by the University of California San Diego.
The marine sanctuary is located in the Gulf of Mexico, about 100 miles south of the Texas coast.
“The juvenile life stage for oceanic mantas has been a bit of a black box for us, since we’re so rarely able to observe them,” said Stewart, in the statement. “Identifying this area as a nursery highlights its importance for conservation and management, but it also gives us the opportunity to focus on the juveniles and learn about them. This discovery is a major advancement in our understanding of the species and the importance of different habitats throughout their lives.”
The graduate student also serves as executive director of the Manta Trust, a global manta conservation program.
Sites where the large plankton-eating manta rays congregate are typically far from coastal areas, making it hard for scientists to study the animals in the wild. “Baby mantas are virtually absent from nearly all manta populations around the world, so even less is known about the juvenile life stage,” explained the University of California San Diego, in its statement.
After studying 25 years of dive log and photo identification data, Stewart and marine sanctuary staff found that about 95 percent of the mantas visiting the Flower Garden Banks site are juveniles. The manta rays had an average wingspan of 7.38 feet. Oceanic manta rays can reach an adult wingspan of 23 feet.
“Nowhere else in the world has a manta ray nursery area been recognized — which heightens the importance of the sanctuary for these pelagic species,” said George P. Schmahl, superintendent of Flower Garden Banks National Marine Sanctuary.
“The discovery of the sanctuary as a nursery area for the species raises many more questions, some of which we can hopefully start studying with Josh Stewart and other partners.”
The results of the research are published in the journal Marine Biology.
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