Alex Mustard / Blacktip reef sharks (Carcharhinus melanopterus) circling over a shallow coral garden (Acropora spp.). Misool, Raja Ampat, West Papua, Indonesia. Misool Marine Protected Area. Ceram Sea. Tropical West...

Alex Mustard / Western clown anemonefish (Amphiprion ocellaris) poses with a large, dominant female behind. The clownfish in the foreground is probably a juvenile. Bitung, North Sulawesi, Indonesia. Lembeh Strait, M...

Georgette Douwma / Kaleidoscopic image of soft corals (Dendronephthya sp.) and a red sponge. Egypt, Red Sea.

Georgette Douwma / Kaleidoscopic image of Brittlestar (Ophiothrix sp.) on Sea pen (Virgularia sp.). Rinca, Indonesia.

Georgette Douwma / Kaleidoscopic image of soft coral. West Papua, Indonesia.

Shane Gross / Caribbean reef shark (Carcharhinus perezi) patrolling coral reef with Schoolmaster snapper (Lutjanus apodus) and other fish. Caribbean Sea off Gardens of the Queen National Park, Cuba.

Alex Mustard / Hard corals (Acropora microclados) growing in shallow water, reflected in the surface, Gubal Island, Egypt. Strait of Gubal, Red Sea.

Alex Mustard / Soft corals (Dendronephthya hemprichi) growing in very shallow water in the shade provided by a jetty, while a school of Silversides (Atherinomorus lacunosus) circle. Berenice Jetty, Aqaba, Jordan. Gu...

SCOTLAND: The Big Picture / Anemones (Sagartia sp) living amongst a kelp forest, North Rona, Outer Hebrides / Western Isles, Scotland, UK, July.

Tony Wu / Paguritta coral hermit crabs (Paguritta sp) looking out from burrows in coral, Papua New Guinea

Tony Wu / Hardyhead silversides (Atherinomorus lacunosus) swarming around the coral-encrusted remains of a portion of the jetty at Samarai Island in Milne Bay, Papua New Guinea

Tony Wu / Hard coral (Platygyra) in shallow blue water, Ambon, Indonesia