As spring creeps up on us, we’re all excited to get out in the field and see what early migrants have shown up. Although not many songbirds are moving yet in March, there are plenty of waterfowl around. One group of waterfowl that regularly creates ID problems is the brown streaky ducks – females of Mallard, Gadwall, Northern Pintail, Northern Shoveler, and Blue-winged and Green-winged Teal. When most of us look at waterfowl, we tend to cheat a little and identify the females at least partially based on the distinctive males they are associated with. Unfortunately, using the associating males as the sole basis of an identification is guaranteed to result in mistakes. However, the males do provide invaluable reference points and can certainly be used to help learn the females. In particular, noticing differences in size and structure between those flashy male ducks will provide some of the most useful hints to the identity of the females. Other features such as leg color and wing pattern are also very useful ID features but are often not visible on swimming birds. The following photo captions highlight some of the most useful features to look for on these species while swimming, when their distinctive wing patterns are usually not visible.
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Figure 1 – Male and female Mallards (closer birds) and Gadwalls, December, New Jersey. The male Mallard and Gadwall are readily distinguished and provide a helpful starting point for sorting out the females. Notice the male Gadwall’s slimmer bill and steeper forehead compared to those of the male Mallard and see if you can detect the same differences between the females. Also notice the female Gadwall’s less contrasting face pattern and different bill pattern with orange confined to the edges. Finally, notice that the Mallard’s longer tail is mostly white. In flight, Gadwall’s different wing pattern and contrasting white belly would add additional field marks. Photo by Michael O’Brien. |
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Figure 2 – Female Northern Shoveler, January, Florida. Like female Mallard, female Northern Shoveler is brown and streaky with a white tail. However, it is also slightly smaller and, more obviously, has a massive bill just like the male’s. It is also worth noticing the shoveler’s prominent white tertial edges, a useful distinction from Mallard when dealing with sleeping birds. Wing patterns are distinctly different on flying birds. Photo by Michael O’Brien. |
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Figure 3 – Female Northern Pintails, January, Florida. Compared to female Mallards, female Northern Pintails are much slimmer and longer-necked (notice the similarity in shape to a male Northern Pintail). Although they don’t have the male’s tail streamers, their tails are still relatively long and pointy. Their overall color is colder brown than Mallard’s though their unpatterned heads are tinged cinnamon (female Mallard is brightest on the breast, not the head). Instead of orange and black, their bills are lead gray. Their legs are also grayish rather than orange. Photo by Michael O’Brien. |
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Figure 4 – Female Blue-winged Teal, January, Florida. Both Blue-winged and Green-winged Teal are considerably smaller than the other four species discussed here, a difference that is obvious in direct comparison but perhaps less so on a lone bird. Compared to Green-winged, Blue-winged has a larger, darker bill and a more even slope from bill to forehead. The face pattern is bolder, with a prominent broken eye ring. Blue-wing’s overall color is a slightly colder brown color than Green-winged though the difference is subtle and somewhat variable. Wing pattern is an easy distinction between the two species though it is typically not visible on swimming birds. Photo by Michael O’Brien. |
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Figure 5 – Female Green-winged Teal, January, Florida. Compared to Blue-winged, notice this bird’s shorter, slimmer bill and more buff-tinged overall color. The face pattern looks dirtier and lacks Blue-wing’s bold eye-ring. A most useful distinction that is often more obvious at a distance than up close is the contrasting whitish stripe on the sides of the undertail coverts. This area is uniformly streaked on Blue-winged, blending in with the rest of the bird. The bold green wing-patch visible here is not a distinction from Blue-winged Teal. All teal have green secondary patches (that’s why they’re called “teal,” after all) though Green-wingeds do display them more commonly than do Blue-wings. Photo by Kevin Karlson. |
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