There are two yellowleg species regularly found in the United States and Canada. Both species nest in northern Canada and into Alaska. Both migrate south in the winter to all three coasts and into Mexico. The Great Yellowlegs is more widespread in the winter, but both species are generally common during migration and in their winter ranges.
These two long-legged shorebirds can be easy to confuse with each other, and with at least one other species. They are very similar in appearance but can be told apart with a little experience
Lesser Yellowlegs are Killdeer-sized sandpipers, but with long legs that can sometimes be covered in mud. The is bill slightly longer than its head. Most winter in the Tropics. In April they begin to show back up in small flocks as the fly around the Gulf of Mexico, not across it.
A small flock of feeding yellowlegs almost always Lesser and not Greater Yellowlegs. The call is usually one or sometimes more “teewee” sounds, usually of the same pitch.
Greater Yellowlegs have a bill that is about twice the length of its head, and sometimes shows a slight upward curve. It tends to be more heavily barred than the lesser and tends to be loner. The call of the Greater is much stronger than the Lesser, usually 3 or more descending notes.
There is one exception. One of the image pairs has a Solitary Sandpiper instead of the Greater Yellowlegs. See if you can spot it.
The head shapes of these two birds are quite different, adding to the possible confusion in identification. The difference is just from different postures.
All images © Greg Lavaty.
Note the shorter, thinner and more pointed bill of the Lesser. As the name suggests, the Greater Yellowlegs is the larger of the two species, but size can be confusing unless there is a comparison with another species.
The bill of the Greater Yellowlegs is sometimes slightly curved upward, a feature not shown well in this image of a Greater Yellowlegs. In winter-plumaged birds, the bill is two-toned.
The bill on this Lesser Yellowlegs is thin and straight. Lesser Yellowlegs have a slightly less robust appearance the Greaters.