SARASOTA, Fla. -- They’re known as one of the giants of the ocean. Manta rays can reach 28 feet across and one, a younger smaller one, was spotted off Pinellas County.

“Manta Ray sightings are rare along this coast,” said Kim Hull, senior scientist at Mote Marine.

Fishermen say in the 1950s they would see schools of giant manta rays swimming off Sarasota beaches. But they suddenly disappeared. A few days ago one was spotted off Pinellas near Shell Key Preserve by Tampa Bay Watch. They were doing boat safety drills when they spotted one measuring between 7-9 feet.

Hull said, “It looks like a juvenile sighting. Manta rays are born at 5-6 feet across get quite large, up to 25-27 feet for the giant mantas. We’ve only had six confirmed sightings since I started with the research program here in 2009. This sighting is very exciting.”

Hull says it’s unusual to see one in shallow water in the gulf and to see it this time of year.

“Most of our sightings are late summer to early fall, but manta rays are filter feeders. They eat small planktons in the water, so there might be a plankton bloom they’ll be attracted to. Is there more food closer to shore for them to feed?”

Overfishing has hurt the manta ray population. Hull says they were harpooned or caught with nets or entangled in nets for other catch.

In the late 1800s and early 1900s, manta rays were caught for sport. President Theodore Roosevelt harpooned a few in his day.

The animal is protected in international waters and many countries have bans in place (Florida they're a protected species) but humans still have an impact.

“A new thing is microplastics in the ocean … these guys are filter feeders, and all the plastic sits in the ocean,” said Hull.

Mote has been able to tag only one manta ray in the gulf in 2013.

“We got a satellite tag on it. We followed it for 30 days stayed offshore between here and off Sanibel Captiva area,” said Hull.

If you are lucky to see one, Hull said enjoy the moment. “Cherish the sighting. It’s an amazing animal to watch fly through the water.”

Scientists say manta rays are mysterious animals, Very little is known.

What we do know is they live between 20 or 30 years. The gestation period is one or two pups a year. If you see one, scientists ask you snap a photo, mark the spot and report it to Mote or FWC.