Thousands of Golden Rays off the coast of Mexico

Thousands of Golden Rays are seen here gathering off the coast of Mexico. The spectacular scene was captured as the magnificent creatures made one of their biannual mass migrations to more agreeable waters.

Gliding silently beneath the waves, they turned vast areas of blue water to gold off the northern tip of the Yucatan Peninsula. Sandra Critelli, an amateur photographer, stumbled across the phenomenon while looking for whale sharks.

Measuring up to 7ft (2.1 meters) from wing-tip to wing-tip, Golden rays are also more prosaically known as cow nose rays.

They have long, pointed pectoral fins that separate into two lobes in front of their high-domed heads and give them a cow-like appearance. Despite having poisonous stingers, they are known to be shy and non-threatening when in large schools.

The population in the Gulf of Mexico migrates, in schools of as many as 10,000, clockwise from western Florida to the Yucatan .

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