Alex Mustard / Two Whale sharks (Rhincodon typus) feeding on fish eggs at the surface, Isla Mujeres, Quintana Roo, Yucatan Peninsula, Mexico, Caribbean Sea.

Alex Mustard / A school of lesser devil rays (Mobula hypostoma) flying through sunbeams as they feed. Isla Mujeres, Quintana Roo, Yucatan Peninsula, Mexico. Caribbean Sea.

Alex Mustard / Whale shark (Rhincodon typus) silhouette of shark feeding on floating fish eggs (not visible) just below the surface in calm weather, with snorkeller taking photos nearby, Isla Mujeres, Quintana Roo,...

Alex Mustard / Whale shark (Rhincodon typus) feeding on fish eggs (visible as white blobs) at the surface in calm weather, with another whale behind. Isla Mujeres, Quintana Roo, Yucatan Peninsular, Mexico, Caribbean...

Alex Mustard / Whale shark (Rhincodon typus) silhouette, feeding on floating fish eggs (not visible) just below the surface in calm weather. Note the bow wave ahead of the shark. Isla Mujeres, Quintana Roo, Yucatan...

Pete Oxford / Two Common Bottlenose Dolphin (Tursiops truncatus) in shallow water. Punta Allen, Sian Ka'an Biosphere Reserve, Quintana Roo, Yucatan Peninsula, Mexico.

Pete Oxford / Red Mangrove (Rhizophora mangle) and fish. Sian Ka'an Biosphere Reserve, Quintana Roo, Yucatan Peninsula, Mexico.

Pete Oxford / Beach trash, Sian Ka'an Biosphere Reserve, Quintana Roo, Mexico

Pete Oxford / Beach trash, Sian Ka'an Biosphere Reserve, Quintana Roo, Mexico

Robert Smith / Diver exploring a freshwater Limestone sinkhole / Cenote called 'The Pit' - a traverse to 'The Blue Abyss' with stalactites and stalagmites, Tulum, Quintana Roo, Mexico, September 2008. Model released

Doug Perrine / Female Bull sharks (Carcharhinus leucas) in seasonal breeding aggregation with Sharksuckers (Echeneis naucrates) Playa del Carmen, Cancun, Quintana Roo, Yucatan Peninsula, Mexico (Caribbean Sea)

Alex Mustard / An extreme close up using circular fisheye lens of the mouth of a Whale shark (Rhincodon typus) as it feeds on fish eggs at the surface, Isla Mujeres, Quintana Roo, Yucatan Peninsula, Mexico, Caribbea...