SOUTH PADRE ISLAND - The largest fish species on Earth was spotted off Rio Grande Valley shores.

Professor of biology, Dr. Tim Bonner was fishing in Port Mansfield, off the jetties Tuesday.

"And we noticed then it was a bait ball there at the surface."

The slow-moving whale shark came as close as one of the sand bars for a meal.

These species roam the tropics all around the world and are often seen off the coast of the Yucatan Peninsula.

Bonner says they've been spotted out there before; they're drawn to warm water.

He suspects the water off Port Mansfield is now warm enough to support them.

"He's probably sticking around because he was getting some meals," says Bonner.

The whale shark will keep moving, keep feeding on plankton and fish and fueling its large body.

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