See more beautiful images from under the sea
Life underwater is a fascinating world as this set of stunning images from ocean explorer William Winram shows.
The keen diver was navigating the waters of the Cabo Pulmo Marine Protected area in Baja California, Mexico, when a school of fish formed a vortex in the waters around him.
Winram, 50, had been in the region tagging tiger and bull sharks as part of a conservation project. But due to a band of warm water known as 'El Nino', the sharks were staying in the deeper water. He managed to capture these amazing images while waiting for the sharks to emerge - all while holding his breath.
The Canadian conservationist said: 'We saw some extraordinary sights and had some amazing encounters while diving on a breath-hold. The images, all taken with natural light, show just what can happen when you create a protected area and manage it effectively.'
Winram explained that he witnessed an increased in biomass, size and numbers of marine creatures since he last visited 25 years ago but conceded that some of the bigger specimens had been fished out of the waters.
He added: 'All in all, it was impressive to see the changes in the area for the better and to also see that it is the local population that is managing, protecting and enforcing within the marine protected area.
Photographer William Winram