Cassin's Auklet Similar Species Comparison
Main SpeciesCassin's Auklet
Adult
Small dark gray seabird with a round head. With close views note pale eye, white crescent above the eye, and pale spot at the base of the bill.
© Yousif Attia / Macaulay LibraryBritish Columbia, September 14, 2014Adult
Small dark gray seabird that shows a thin whitish stripe on the underwing in flight.
© Dorian Anderson / Macaulay LibraryCalifornia, July 08, 2017Adult
Small, chunky dark gray seabird with light gray flanks.
© Gary Maschmeyer / Macaulay LibraryOregon, August 18, 2016Adult
Small seabird with a small dark bill (pale base not always visible).
© Robin Corcoran / Macaulay LibraryAlaska, August 16, 2012Adult
Small dark gray seabird with white crescents above and below the eye. Able to take flight directly from the water.
© Carey Bergman / Macaulay LibraryBritish Columbia, May 27, 2014Similar SpeciesRhinoceros Auklet
Breeding adult
Rhinoceros Auklets are larger than Cassin's Auklets, with larger, longer bills that are yellowish. In breeding plumage, Rhinoceros have two white facial streaks that Cassin's lacks.
© Ken Langelier / Macaulay LibraryBritish Columbia, August 24, 2016Similar SpeciesMarbled Murrelet
Breeding
Breeding Marbled Murrelets are more slender than Cassin's Auklets, with a longer, thinner bill. They are browner with light-colored mottling (or marbling) instead of Cassin's more uniform dark gray color.
© Brian Sullivan / Macaulay LibraryAlaska, May 18, 2012Similar SpeciesMarbled Murrelet
Nonbreeding
In nonbreeding plumage, Marbled Murrelets are boldly patterned white and black, whereas Cassin's Auklets are dark grayish all year.
© Ryan Shaw / Macaulay LibraryWashington, September 17, 2017Similar SpeciesParakeet Auklet
Breeding
Parakeet Auklets have very thick, orange bills and a white chest and belly, unlike Cassin's Auklet's dark bill and uniform grayish coloration.
© Colin Sumrall / Macaulay LibraryAlaska, May 22, 2017Rotate Your Device to Better Compare
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Species in This Family
Auks, Murres, and Puffins(Order: Charadriiformes, Family: Alcidae)
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