Sandra Critelli/Barcroft Media

Sandra Critelli/Barcroft Media

Sandra Critelli/Barcroft Media

Sandra Critelli/Barcroft Media

It was the end of this June when amateur photographer Sandra Critelli , who was looking for whale sharks, found herself in the right place at the right time to experienced nature at its best. Her boat was surrounded by thousands of rays swimming together like autumn leaves floating in a sunlit pond... gently moved by the wind. The images speak for themselves.The spectacular scene was captured as the magnificent creatures made one of their biannual mass migrations to more agreeable waters as they follow the clockwise current from Mexico's Yucatan peninsula to western Florida in schools of as many as 10,000. These particular kind of rays are known as Cow-nose rays (Rhinoptera bonasus) due to their distinctive, highdomed heads, giving them a curiously bovine appearance. They measure up to 7ft (2.1 metres) from wing-tip to wing-tip and have a long poisonous sting on their tail capable of killing a human even though they are pretty shy and rarely become dangerous.