Why are Florida's 'urban manta rays' visiting some particularly dangerous spots?
Understanding why marine animals are using some places and not others is crucial to minimizing our impact on them. Recently, Nortek’s new Eco acoustic doppler current profiler has been helping one marine biologist, with no previous experience in using oceanographic instruments, characterize current flows in one of the manta ray‘s more unusual shallow-water coastal habitats with simplicity and ease.
Powerful yet graceful, manta rays top almost everyone’s list of must-see marine animals. While people flock to places like Indonesia or the Maldives to watch these gentle giants, one location has gone relatively unnoticed – South Florida. “I lived in Florida working as a sea turtle biologist, and a lot of data collection involved being on the beach all day,” recounts Jessica Pate, a marine biologist with the Marine Megafauna Foundation. “Sometimes I would notice these big, black shapes swimming right next to shore in less than a meter of water.”
Surprised to see manta rays, Pate searched for more information but found very little. “I know hundreds of people researching sea turtles, and I couldn’t believe that no one was studying manta rays [in South Florida],” she says.
Pate has been working hard to rectify the lack of information on South Florida’s manta rays, and recently published a major study that revealed some key insights about the mantas that frequent South Florida – they are primarily juveniles.
Manta rays favor shallow water with strong currents
With Florida’s coast so highly developed, it is a surprising location for a nursery area. What’s more, these particular “urban manta rays” are also singling out some particularly hazardous locations.
“There’s this man-made inlet [Boynton Beach Inlet] that’s known for being one of the most dangerous inlets because it’s very skinny with seawalls, and boats come flying through. I try to avoid it at all costs,” Pate says.
Despite the risks, and the shallow water (Pate estimates Boynton Beach Inlet’s maximum depth to be around 10 m), the inlet seems to be a popular location for the manta rays. “They will come around and face into the current, which is really strong, and just sit,” says Pate, who sees groups of up to six manta rays sitting in the inlet for hours at a time.“You just watch boat, after boat, after boat go right over them,” says Pate, noting that the manta rays can be in just a few meters of water when the boats are above them. “It seems like a really horrible place to be, so I’m really curious as to why they’re choosing that inlet…”
Read the rest of the story at Nortek.
