Duck Id: Greater Scaup Vs. Lesser Scaup Vs. Ring-Necked Duck

As a waterfowl hunter, being able to identify ducks on the fly quickly is critical to obeying waterfowl regulations. This isn’t always easy, especially when some duck species look as similar as the Greater and Lesser Scaup; then we throw in the Ring-Necked Duck, a third species with similar characteristics.

Luckily, most waterfowl hunting laws are lenient when discerning between these three species, commonly known as bluebills and ringnecks. However, that doesn’t excuse us as hunters from being able to tell the subtle differences.

In college, I had to take a waterfowl identification test using only pictures; while I passed it, I had to look at the greater and lesser scaup longer than most other species, and the ring-necked ducks almost threw me off. Let’s find out why!

Visual Differences between the Greater Scaup, Lesser Scaup, and Ring-Necked Duck

These drakes look very similar from a distance, with a dark, almost black head, gold eyes, and grayish body. The hens are nearly impossible to distinguish because they’re brown with a white face patch. Except for the ringneck hen, whose bill has a white ring around that can be used to identify the species quickly.

Upon closer inspection of the drakes, you’ll notice lesser scaup are smaller than greater scaup. The greater scaup has a rounded head, whereas the lesser scaup looks less rounded. The lesser also has a taller narrower head.

The ring-necked drake has a solid black back and a cone-shaped head. The bill is the quickest way to identify the difference between ringneck drakes and scaup drakes.

The bills of the scaup are shaped differently, but it’s easiest to see that the bill of the lesser will be smaller because it’s a smaller duck. The ring-necked duck has two white rings on its bill, and the black tip is more pronounced.

The head colors also begin to reveal themselves as we get closer, and this is probably the easiest way to quickly identify the birds though it can be a little tricky.

Greater scaup have green heads, and less scaup have purple heads. I remember it by green=greater.

Both species can have a touch of both colors, but the majority of the great scaup drakes head will be green.

For ringnecks, the drakes have a dark iridescent reddish-brown and black head. Their name comes from the reddish-brown ring at the base of their necks.

Another way to identify the differences between the three species is to look at the differences in where they tend to be found.

Typical Ranges

Whenever the annual duck surveys are conducted, greater and lesser scaup are counted together because they’re difficult to distinguish at a distance.

While they are found in similar areas at specific times of the year, such as when the surveys are conducted, during other times, you’re more likely to encounter one species over the other in certain areas.

Lesser scaup often prefer freshwater over saltwater, whereas greater scaup prefer saltwater over freshwater. So you’ll find lesser scaup in the Central and Mississippi flyways more often than you will find greater scaup.

You’ll also find ringnecks primarily in the Central and Mississippi flyways.

However, you can and will find scaup together across various flyways, primarily on large open water bodies. They’re diving ducks, which means they dive to feed.

Ring-necked ducks prefer to dive in shallow water for aquatic plants, insects, snails, and clams.

Bluebills mainly feed on muscles and submerged vegetation, depending upon the season and what’s locally available. According to scientific studies, greater scaup tend to eat more snails and plants than lesser scaup, whereas lesser scaup tend to eat more mussels than greater scaup.

Parting Shots

Though the differences in size, head color, body color, habitat, and diet preferences are subtle, they’re sometimes needed to identify between the species, especially from a distance.

Not only are greater scaup larger, but they also have green heads, while lesser scaup have purple heads.

Green=Greater scaup

The ringneck bill is a dead giveaway for identifying this species, compared to scaup species, which is why it’s typically the first thing I look at, followed by the head.

That’s how I aced my duck identification test in college, and I continue to use it when identifying ducks in the field!