The tufted duck and the greater scaup are two species of diving ducks that belong to the genus Aythya. Both species are found in North America and Eurasia and can be difficult to distinguish in the field due to their similar size and coloring. However, there are some key differences between these two diving ducks in terms of physical features, habitat, diet, breeding behavior, and conservation status.
Physical Features
The tufted duck and greater scaup have similar body shapes and sizes. Adult males of both species have black heads, necks, breasts, and tails contrasting with white flanks and bellies. Females have more subdued brownish-gray plumage overall. However, there are several physical differences that allow for identification:
Tufted Duck
– Black back and upperwing coverts
– Long, drooping black crest on the head
– Yellow eyes
– Blue-gray bill with black tip
Greater Scaup
– White sides and back
– Rounded head shape without crest
– Pale blue eyes
– Blue bill with black nail near tip
The tufted duck is slightly smaller, weighing 1.1-1.4 lbs on average compared to the greater scaup at 1.5-3.3 lbs. Wingspans are around 26 inches for tufted ducks and 30 inches for greater scaups.
Habitat
Both species inhabit lakes, ponds, rivers, estuaries, and coastal waters. However, there are some habitat differences:
Tufted Duck
– Favors small ponds and lakes
– Tolerates brackish and saltwater habitats
– Often found close to shore
Greater Scaup
– Prefers larger, deeper lakes and bays
– Rarely ventures into saltwater
– Tends to stay further from shore
Tufted ducks do well on urban waters and are more tolerant of human disturbance. Greater scaups prefer more pristine wetlands and keep their distance from areas of heavy human activity.
Diet
As diving ducks, both species feed underwater on aquatic invertebrates and vegetation. However, their diets differ somewhat:
Tufted Duck
– Feeds mainly on insects, snails, and other invertebrates
– Also eats seeds and vegetation from pond bottoms
– Makes shallow dives, less than 10 feet deep
Greater Scaup
– Consumes mostly mollusks like clams and mussels
– Also eats some crustaceans and aquatic plants
– Can dive up to 60 feet to forage
The greater scaup has a more specialized diet focused on mollusks which it is able to access by diving much deeper than the tufted duck. The tufted duck is a bit more of a generalist.
Breeding
The breeding behaviors of these species have some similarities but also some key differences:
Tufted Duck
– Nests near water in reeds and vegetation
– Lays 6-15 eggs
– Incubation lasts 24-28 days
– Ducklings can feed themselves shortly after hatching
Greater Scaup
– Nests farther from water in grasslands or open forests
– Lays 8-12 eggs
– Incubation lasts 21-27 days
– Ducklings require parental care for feeding and protection
Tufted ducks begin breeding at age 1 year while greater scaups start at age 2. Tufted ducks are more social and nest closer together than the solitary nesting greater scaup.
Conservation Status
The tufted duck and greater scaup have differing population trends and conservation concerns:
Tufted Duck
– Population increasing overall
– Listed as Least Concern by IUCN
– Tolerant of human activities and habitat changes
Greater Scaup
– Population declining significantly
– Listed as Least Concern but with decreasing numbers
– Vulnerable to wetland loss and degradation
Greater scaup numbers have dropped by an estimated 65% since the 1980s, potentially due to acid rain impacts, pollution, and loss of breeding habitat. Their specialized diet may also make them more sensitive to ecosystem changes. More conservation focus is needed for the greater scaup.
Identification Tips
Here are some quick tips for identifying these similar diving duck species:
Tufted Duck
– Crested head
– Yellow eye
– Black back
– Small size
– Found on ponds and lakes
Greater Scaup
– Round head
– Blue eye
– White back
– Large size
– Found on bays and large lakes
Getting a clear look at the head profile and eye color is most helpful. Also note the habitat as greater scaups prefer larger, deeper water bodies.
Conclusion
In summary, while the tufted duck and greater scaup share similarities as diving ducks, there are clear differences in physical features like the head crest and back color, preferred habitat and diet, breeding behaviors, and conservation status. Being able to distinguish between these two species is important for bird identification and supporting conservation efforts, particularly for the declining greater scaup population. Paying attention to field marks like eye color and head shape along with behaviors and habitat can help anyone become better at identifying these birds. With a little practice, telling a tufted duck from a greater scaup becomes a much easier task.
