Alex Mustard / Striped mackerel (Rastrelliger kanagurta) shoal swimming with open mouths, filtering for zooplankton. Marsa Shouna, Port Ghalib, Marsa Alam, Egypt. Red Sea

Doc White / Blue Whales (Balaenoptera musculus) throat inflated, filter feeding at sea surface. California, USA. Sequence 1 of 2.

Alex Mustard / Basking shark (Cetorhinus maximus) rear view of shark feeding at the surface on plankton, Cairns Of Coll, Isle of Coll, Inner Hebrides, Scotland, UK, North East Atlantic Ocean, June

Alex Mustard / Basking shark (Cetorhinus maximus) feeding at the surface on plankton, Cairns Of Coll, Isle of Coll, Inner Hebrides, Scotland, UK, North East Atlantic Ocean, June

Alex Mustard / 2020VISION / Light-bulb sea squirts (Clavelina lepadiformis), a colonial filter feeding invertebrate, fluoresce green when photographed under deep blue light. Shetland Islands, Scotland, UK, June. Did you know? Se...

Alex Mustard / 2020VISION / Light-bulb sea squirts (Clavelina lepadiformis), a colonial filter feeding invertebrate, fluoresce orange when photographed under deep blue light. Shetland Islands, Scotland, UK, June. Did you know? L...

Alex Mustard / 2020VISION / Light-bulb sea squirts (Clavelina lepadiformis), a colonial filter feeding invertebrate, Shetland Islands, Scotland, UK, June

Doug Perrine / Reef manta ray (Manta alfredi formerly Manta birostris) barrel roll filter feeding on plankton, Hanifaru Bay, Baa Atoll, Maldives, Indian Ocean, October

Doug Perrine / Reef manta rays (Manta alfredi formerly Manta birostris) vortex / cyclone feeding on plankton, Hanifaru Bay, Hanifaru Lagoon, Baa Atoll, Maldives, Indian Ocean, October

Doug Perrine / Reef manta rays (Manta alfredi formerly Manta birostris) filter feeding on plankton among Silverside fish that are also feeding on the plankton, Hanifaru Bay, Hanifaru Lagoon, Baa Atoll, Maldives, Ind...

Andy Rouse / Whale shark (Rhincodon typus) filter feeding, surrounded by other smaller fish, Ningaloo Reef, Western Australia

Andy Rouse / Whale shark (Rhincodon typus) filter feeding, surrounded by other smaller fish, Ningaloo Reef, Western Australia

Anup Shah / Lesser flamingo {Phoeniconaias minor} chick learning to filter-feed in water, Lake Nakuru NP, Kenya

Jurgen Freund / Whale shark filter feeding {Rhincodon typus} Indo-pacific

Georgette Douwma / Manta rays filter feeding at sea surface, Red Sea off Sudan

Martin Dohrn / Mosquito {Culex pipiens} larvae filter feeding at surface of water. UK

Norbert Wu / Goose Barnacle (Lepas sp) group filter feeding, attached to fisherman's float, North Pacific

Pete Oxford / Whale Shark (Rhincodon typus) filter feeding at floating fishing platform, Cenderawasih Bay, West Papua, Indonesia

Norbert Wu / Whale Shark (Rhincodon typus) feeding on plankton off Isla Mujeres, Mexico

Hiroya Minakuchi / Blue Whale (Balaenoptera musculus) filter feeding, pleated throat expands during feeding, Sea of Cortez, Mexico

Flip Nicklin / Gray Whale (Eschrichtius robustus) bottom feeding, Vancouver Island, British Columbia, Canada

Flip Nicklin / Gray Whale (Eschrichtius robustus) filter feeding, Tofino, Vancouver Island, British Columbia, Canada

Nick Upton / Acorn barnacles (Balanus perforatus) filter feeding underwater in a rock pool, Rhossili, Gower Peninsula, Glamorgan, Wales, UK, August.

Nick Upton / Acorn barnacles (Balanus perforatus) filter feeding underwater in a rock pool, Rhossili, Gower Peninsula, Glamorgan, Wales, UK, August.

David Hall / Red-trumpet calcareous tubeworm (Serpula columbiana) Browning Pass, Queen Charlotte Strait, British Columbia, Canada. September.Most of this worm is hidden within a hard, calcareous tube; the visible...

Shane Gross / Whale shark (Rhincodon typus) feeding on fish spawn, Isla Mujeres, Mexico. August.

Shane Gross / Whale sharks (Rhincodon typus), two, feeding on fish spawn, Isla Mujeres, Mexico, non-ex

Tui De Roy / Reef manta ray (Manta alfredi) tourists swimming with mantas filter feeding, Dhikkurendho Reef, Raa Atoll, Maldives

Tui De Roy / Reef manta rays (Manta alfredi) filter feeding on plankton, Dhikkurendho Reef, Raa Atoll, Maldives

Tui De Roy / Reef manta rays (Manta alfredi) filter feeding on plankton, Dhikkurendho Reef, Raa Atoll, Maldives

Tui De Roy / Reef manta rays (Manta alfredi) filter feeding on plankton, Dhikkurendho Reef, Raa Atoll, Maldives

Tui De Roy / Reef manta rays (Manta alfredi) tourists swimming with mantas filter feeding on plankton, Dhikkurendho Reef, Raa Atoll, Maldives

Tui De Roy / Reef manta rays (Manta alfredi) filter feeding on plankton, Dhikkurendho Reef, Raa Atoll, Maldives

Tui De Roy / Reef manta rays (Manta alfredi) filter feeding on plankton, Dhikkurendho Reef, Raa Atoll, Maldives

Tui De Roy / Reef manta rays (Manta alfredi) filter feeding on plankton, Dhikkurendho Reef, Raa Atoll, Maldives

Tui De Roy / Reef manta rays (Manta alfredi) filter feeding on plankton, Dhikkurendho Reef, Raa Atoll, Maldives

Tui De Roy / Reef manta ray (Manta alfredi) filter feeding on plankton. Madhivafaru Reef, Raa Atoll, Maldives

Tui De Roy / Reef manta ray (Manta alfredi) filter feeding on plankton. Madhivafaru Reef, Raa Atoll, Maldives

Tui De Roy / Reef manta rays (Manta alfredi) filter feeding on plankton Hanifaru Bay, Raa Atoll, Maldives

Tui De Roy / Reef manta rays (Manta alfredi) filter feeding in atoll passes and lagoons Hanifaru Bay, Raa Atoll, Maldives

Tui De Roy / Reef manta rays (Manta alfredi) filter feeding in atoll passes and lagoons Hanifaru Bay, Raa Atoll, Maldives

Tui De Roy / Reef manta rays (Manta alfredi) filter feeding in atoll passes and lagoons Hanifaru Bay, Raa Atoll, Maldives

Tui De Roy / Reef manta rays (Manta alfredi) filter feeding in atoll passes and lagoons Hanifaru Bay, Raa Atoll, Maldives

Tui De Roy / Reef manta ray (Manta alfredi) filter feeding on plankton. Vandhoo Thila, Raa Atoll, Maldives

Tui De Roy / Reef manta rays (Manta alfredi) filter feeding on plankton. Vandhoo Thila, Raa Atoll, Maldives

Tui De Roy / Reef manta rays (Manta alfredi) filter feeding on plankton. Vandhoo Thila, Raa Atoll, Maldives

Tui De Roy / Reef manta ray (Manta alfredi) filter feeding on plankton. Vandhoo Thila, Raa Atoll, Maldives

Tui De Roy / Reef manta rays (Manta alfredi) filter feeding on plankton. Vandhoo Thila, Raa Atoll, Maldives