Greater Scaup
Aythya marila
- KingdomAnimalia (Animals)
- PhylumChordata (Cordats)
- ClassAves (Aus)
- OrderAnseriformes
- FamilyAnatidae (Anàtids)
- GenusAythya (Scaups, Pochards, and Allies)
- SpeciesAythya marila (Greater Scaup)
The greater scaup (Aythya marila), just scaup in Europe or, colloquially, "bluebill" in North America, is a mid-sized diving duck, larger than the closely related lesser scaup and tufted duck. It spends the summer months breeding in Iceland, east across Scandinavia, northern Russia and Siberia, Alaska, and northern Canada. During the winter, it migrates south to the coasts of Europe, eastern Asia, and North America. Male greater scaup average slightly larger than the females but with much overlap; they have a light blue-grey bill and yellow eyes. Their heads are dark, with a green to purple (depending on light angle) gloss; the breast is black, the belly white, the upperparts pale grey, and the wing shows a strong white stripe. The females are mostly brown, again with white on the wing. Wikipedia →
Closest Relatives at Isle Royale National Park
Canvasback
Aythya valisineria
Ring-necked Duck
Aythya collaris
Lesser Scaup
Aythya affinis
Redhead
Aythya americana
Common Merganser
Mergus merganser
Canada Goose
Branta canadensis
Red-breasted Merganser
Mergus serrator
Common Goldeneye
Bucephala clangula
Mallard
Anas platyrhynchos
Trumpeter Swan
Cygnus buccinator
Bufflehead
Bucephala albeola
Hooded Merganser
Lophodytes cucullatus
📅 Monthly Probability
Fewer than 5 records of Greater Scaup at Isle Royale National Park — not enough to chart months honestly.
☀️ When They're Spotted
Most active during daytime hours (6am–6pm) · across all parks (global)
Global Distribution
Where this species is recorded worldwide. Restricted to human observations from 2019 onwards — the same kind of record and the same period the probabilities on this page are built from, so collar-tracking studies, camera-trap arrays and museum specimens are excluded. Around Santa Rosa that removes 5,924 GPS fixes from a handful of tagged jaguars.
where this species is recorded (GBIF density — it tracks where observers go, not how likely a sighting is) · parks where it occurs — tap a pin for the sighting probability there