Hundreds of whale sharks, the largest fish in the world, have met up for their annual summer congregation in the Gulf of Mexico.
The enormous fish converge in the coastal waters off Cancun from May to September.
Some 250 whale sharks have been sighted so far in a positive sign for the species, New Zealand's 3 News reports.
A record was set in 2009 with 420 whale sharks reported in a single aerial survey.
Local biologist Rafael de la Parra says marine species such as dolphins, stingrays, tuna fish and the whale shark come to the Isla Mujeres, in the Gulf of Mexico, and feed on plankton, algae, krill and small fish or squid, NZ's 3 News says.
De la Parra, of government conservation group Project Domino, thinks the sharks come to reproduce.
Biologists had thought increased sightings indicated that Isla Mujeres was a point along the sharks' migration route, but recent research indicates otherwise.
Meanwhile, the U.K's Daily Mail reports that a man came very close to being swallowed by one of the sharks as he was photographing them.
Mauricio Handler, 49 and father of two, said he was leading an expedition of photographers down there when the moment was captured on camera.
"The picture of the diver staring into the gaping jaws of the shark was an incredible adrenaline rush," the Daily Mail reports.
"They don't have very good eyesight but the diver managed to get out of the way. If he had have been sucked into the massive mouth the shark would have just spat him out."
The Daily Mail reported there were about 600 sharks feeding at the time.
The whale shark is mainly gray in color with a white underside. It is not dangerous to humans and can live between 60 to 150 years.
Whale sharks have been recorded up to 46 feet in length and 15 tonnes in weight, but the average whale shark measures 25 feet in length.
They only swim at about 4.8 kilometers per hour and, unlike many other sharks, they swim by moving their entire bodies from side to side.