In most of New Jersey, swan identification is not a big issue. Most of them are Mute Swans. Mute Swan is generally not a favorite among local birders and naturalists. A native to Europe and Asia, this species was first introduced into North America back in the late 1800s, though fossil evidence indicates it’s natural presence here in relatively recent times. In any case, the current, growing population of Mute Swans is considered highly invasive. Their large size and aggressive nature disrupts or displaces other wetland species, and their consumption of submerged aquatic vegetation has been shown to cause declines in several native waterfowl species. But despite the negative side to their presence here, they are certainly beautiful birds that are worth admiring from a purely aesthetic standpoint. And while you are looking at them, you may as well see if you can find a different species of swan hiding among them. The only other swan species likely to be seen in Cape May and elsewhere in New Jersey is Tundra Swan. They are fairly common but local in the state, though they are seldom seen in large numbers in Cape May. Small groups pass through in November and December and a few birds may remain through the winter and early spring. A third swan species, the Trumpeter Swan, has been seen in Cape May and elsewhere in the state on several occasions. This primarily western species historically occurred along the Atlantic Coast and has been reintroduced in the Great Lakes and Upper Midwest regions. This reintroduced population is growing and some of these birds have been showing up in the Mid-Atlantic states.
Identifying swans can be very tricky. Bill color in adults is usually distinctive and often settles the issue quickly. (Note, however, that some Tundras may show minimal yellow on the bill, and a few even may show a trace of fleshy color to the gape, a character more typical of Trumpeter.) However, structural features are sometimes necessary to really nail down the identification of an odd individual. The photo captions below cover the most useful features in adults. Immature swans can be much more difficult and are beyond the scope of this article. Structural features, much like on adults, are often the most reliable clues. Voice is also a helpful feature on both adults and immatures.
|
Figure 1) Adult Mute Swan, December, New Jersey. This should be a familiar image to most of us. Adult Mute Swan’s orange bill with swollen black knob at the base is very distinctive. Note also the very long tail, a trait unique to Mute Swan. Although not evident here, territorial Mute Swans often take on a characteristic pose with wings lifted as a sail and neck curved in an S-shape. Contrary to their name, they are not entirely mute. They give an odd, relatively soft growling call, quite different from that of other swans. They also hiss at you if you get too close! Photo by Michael O’Brien. |
 |
|
Figure 2) Adult Tundra Swan, December, New Jersey. The black bill with yellow loral spot is distinctive. Note also how much shorter the tail is on this species than on Mute Swan, a helpful field mark on sleeping birds when the bill is tucked away. Formerly known as “Whistling Swan” (before being lumped with the Old World “Bewick’s Swan”), Tundra Swan’s voice is a beautiful, distinctive, deep whistle with a slightly descending quality, which may also be likened somewhat to the bugling call of a crane. Flocks of Tundra Swans flying high overhead are often heard before they are seen. |
 |
|
Figure 3) Adult Trumpeter Swan, January, New Jersey. The most obvious difference from Tundra Swan is the lack of a yellow loral spot on the bill (always lacking in Trumpeter). However, a few Tundra Swans may lack this spot so careful scrutiny of bill structure is necessary to be certain of a possible stray Trumpeter Swan. In particular, note how the bill looks slightly heavier overall with a straighter culmen (upper edge) and a wider area of black where the bill meets the eye (on Tundra, the black looks “pinched” in front of the eye, so the eye often stands out more). Also note how the line from the eye to the gape is straighter on Trumpeter, and more curved on Tundra. As on Tundra Swan, the tail is distinctly shorter than that of a Mute Swan. As their name implies, Trumpeter Swan’s voice is a distinctive trumpet-like bugling (sometimes likened to the noise made by a French taxi cab) with lower, shorter, more resonant notes than Tundra. |
 |
|
Figure 4) Adult Tundra Swan, December, New Jersey. In this head-on view, note how the bill meets the forehead in a relatively straight line, an important distinction from Trumpeter Swan. This bird is missing its right eye, making it difficult to judge the width of black at the lores. |
 |
|
Figure 5) Adult Trumpeter Swan, January, New Jersey. Compared to Tundra, note the more V-shaped juncture between the bill and forehead feathering and also the wide area of black where the bill meets the eye. |
 |
|
Figure 6) Adult Mute Swan, December, New Jersey. When the bill is not visible it is probably impossible to distinguish Tundra and Trumpeter Swans, but this Mute Swan is still readily identifiable by its long tail. Photo by Michael O’Brien. |
 |