Frederique Olivier / Two Blackchin dolphins (Lagenorhynchus australis) surfacing in a fjord, Patagonia, Chile.

Chris & Monique Fallows / Dusky dolphins (Lagenorhynchus obscurus) porpoising, Puerto Madryn, Peninsula Valdez, Argentina, December.

Chris & Monique Fallows / Dusky dolphins (Lagenorhynchus obscurus) porpoising, Puerto Madryn, Peninsula Valdez, Argentina, December.

Chris & Monique Fallows / Dusky dolphins (Lagenorhynchus obscurus) porpoising, Puerto Madryn, Peninsula Valdez, Argentina, December.

Ammonite / Small pod of Atlantic white-sided dolphins (Lagenorhynchus acutus) breaching, Azores, Portugal, July.

Richard Herrmann / Pacific White-sided Dolphin (Lagenorhynchus obliquidens) pod, Nine Mile Bank, San Diego, California

Mark Carwardine / Pacific white-sided dolphin / Lag (Lagenorhynchus obliquidens) swimming fast, showing dorsal fin, Johnstone Strait, Vancouver Island, British Columbia, western Canada

Mark Carwardine / Dusky dolphin breaching {Lagenorhynchus obscurus} Kaikoura, New Zealand

Brent Stephenson / Dusky dolphin (Lagenorhynchus obscurus) somersaults from the water, Kaikoura, Canterbury, New Zealand. February.

Brent Stephenson / Dusky Dolphins (Lagenorhynchus obscurus) porpoising as they swim beside a boat. Off Kaikoura, Canterbury, New Zealand, October.

Martin Camm / Carwardine / Illustration of Pacific white-sided dolphin / Lag (Lagenorhynchus obliquidens), Delphinidae (Wildlife Art Company).

Shattil & Rozinski / Pacific white-sided dolphin (Lagenorhynchus obliquidens) surfacing off the coast of British Columbia, Canada, September