Least Auklet vs Cassin's Auklet
Aethia pusilla compared with Ptychoramphus aleuticus
Side-by-Side Comparison
| Attribute | Least Auklet | Cassin's Auklet |
|---|---|---|
| Scientific Name | Aethia pusilla | Ptychoramphus aleuticus |
| Order | Charadriiformes | Charadriiformes |
| Family | Alcidae | Alcidae |
| Conservation Status | Least Concern | Near Threatened |
| Length | — | — |
| Wingspan | 18.9 cm (7.4 in) | 24.2 cm (9.5 in) |
| Weight | 84.33333333333333 g (2.97 oz) | 175.0 g (6.17 oz) |
| Diet | -- | -- |
| Clutch Size | 1 | 1 |
| Population Trend | — | — |
Habitat Comparison
Conservation Status
Least Concern
Least Auklet
Near Threatened
Cassin's Auklet
About These Birds
Least Auklet
Least Auklet, 15–16 cm, is the smallest auk, breeding in immense colonies (millions) on rocky Aleutian and Bering Sea islands. Dark above, streaked white below; a tiny white plume above the eye. Planktivore; sieves copepods and euphausiids at sea. Makes loud buzzing display choruses at colony.
Cassin's Auklet
Cassin's Auklet, 21–23 cm, is a small, almost entirely dark grey auklet breeding in burrows on rocky North Pacific islands from Baja California to the Aleutians. Feeds almost exclusively on zooplankton — euphausiids and copepods — at night. Highly colonial; winters near shore.