Georgette Douwma / Cock's comb oyster (Lopha cristagalli) covered with encrusting sponge on artificial reef. Mabul, Malaysia.

Magnus Lundgren / Wild Wonders of China / Barnacles and oysters on mangrove in Ha Pak Nai, a mudflat in the Yuen Long District, Hong Kong, China.

Loic Poidevin / Rows of racks used in oyster farming at high tide, Isle de Re, Charente-Maritime, France, July 2017.

Loic Poidevin / Rows of racks used in oyster farming at low tide, Ie de Re, Charente-Maritime, France, July 2017.

Sue Daly / Pacific oyster (Magallana gigas) farm, Herm, British Channel Islands, June 2016

Nick Upton / Pacific oyster / Japanese oyster / Miyagi oyster (Crassostrea gigas) attached to rocks among barnacles, mussels, limpets and anemones, exposed at low tide, Asturias, Spain, August

Philippe Clement / Cultivated oysters (Lophia folium) in bags at oyster farm / oyster park exposed on beach at low tide, Saint-Martin-de-Varreville, Normandy, France, June 2015

Benjamin Barthelemy / Aerial view of oyster hatcheries in Le Banc d'Arguin, Arcachon Bay, Aquitaine, France, June 2014.

Georgette Douwma / Cock's comb oyster (Lopha cristagalli) covered with encrusting sponge on artificial reef. Mabul, Malaysia.

Philippe Clement / Oyster (Ostreidae), barnacles and limpets growing on rock exposed on beach at low tide. Brittany, France, September.

Philippe Clement / Oyster (Ostreidae), barnacles and mussels (Mytillus) growing on rock exposed on beach at low tide. Brittany, France, September.

Ingo Arndt / Giant Pacific Oyster (Crassostrea gigas) colony, invasive species oppresses local Mussel (Mytilus edulis), Sylt Island, North Sea, Germany