The following is a list of marine mammals that have been observed in the Salish Sea. It is adapted from a compilation by Gaydos and Pearson first published in Northwestern Naturalist no. 92 (2011): 79-94 and includes both common and extremely rare visitors.
Species by category
Whales, dolphins, and porpoises (cetaceans)
Orcinus orca (Killer Whale)
- Baird's Beaked Whale (Berardius bairdii)
- Beluga Whale (Delphinapterus leucas)
- Bottlenose Dolphin (Tursiops truncatus)
- Bryde's Whale (Balaenoptera brydei)
- Common Minke Whale (Balaenoptera acutorostrata)
- Cuvier's Beaked Whale (Ziphius cavirostris)
- Dall's Porpoise (Phocoenoides dalli)
- False Killer Whale (Pseudorca crassidens)
- Fin Whale (Balaenoptera physalus)
- Gray Whale (Eschrichtius robustus)
- Harbor Porpoise (Phocoena phocoena)
- Hubbs' Beaked Whale (Mesoplodon carlhubbsi)
- Humpback Whale (Megaptera novaeangliae)
- Killer Whale (Orcinus orca)
- Long-beaked Common Dolphin (Delphinus capensis)
- Northern Right Whale Dolphin (Lissodelphis borealis)
- Pacific White-sided Dolphin (Lagenorhynchus obliquidens)
- Pygmy Sperm Whale (Kogia breviceps)
- Risso's Dolphin (Grampus griseus)
- Short-beaked Common Dolphin (Delphinus delphis)
- Short-finned Pilot Whale (Globicephala macrorhynchus)
- Sperm Whale (Physeter macrocephalus)
- Stejneger's Beaked Whale (Mesoplodon stejnegeri)
- Striped Dolphin (Stenella coeruleoalba)
Seals and sea lions (pinnipeds)
Phoca vitulina (Harbor seal)
- California Sea Lion (Zalophus californianus)
- Guadalupe fur seal (Arctocephalus townsendi)
- Harbor Seal (Phoca vitulina)
- Northern Elephant Seal (Mirounga angustirostris)
- Northern Fur Seal (Callorhinus ursinus)
- Ribbon Seal (Histriophoca fasciata)
- Steller Sea Lion (Eumetopias jubatus)
Sea otters (mustelids)
Enhydra lutris (Sea Otter)
- Sea Otter (Enhydra lutris)
Acknowledgements: Special thanks to Joe Gaydos, SeaDoc Society; Jessie Huggins, Cascadia Research Collective; Kristin Wilkinson, NOAA; Scott Veirs; and the Puget Sound Ecosystem Monitoring Program for their assistance in compiling this list.