Years ago, when I was much younger and learning tricks to better identify birds in the field, I remember learning about “diagnostic” traits to key in on when identifying wild birds flitting about in the underbrush or canopies, flying overhead or at eye level or perched on limb or line.
Two special birds readily come to mind—the hairy woodpecker and the downy woodpecker.
Both species look nearly identical. Yet one of them, the hairy woodpecker, is much larger than the diminutive downy. Yet despite this notable size differential, and if the two species are not observed side-by-side, a novice birder might still misidentify either of the two species of woodpeckers.
Other species of wild birds come to mind, too. The American crow vs. the common raven is one prime example of two different species that look similar, as are numerous others including sandpiper species, wood warblers, certain sparrows and finches, hawks and falcons, waterfowl and many others.
The trick I learned about distinguishing between hairy and downy woodpeckers, is to focus on a certain anatomical structure that each possesses but each are different—their beaks. Whereas both species of course have beaks, the bill of the hairy woodpecker is longer than that of the downy woodpecker. So, you ask? So are the birds!
Indeed, if the bill of the woodpecker is as long as its head is, then your bird is a hairy woodpecker. And if the beak of the bird you’re observing is only half as long as its head, then your bird is a downy woodpecker. Simple as that.
A good field guide to birds will include diagnostic traits/distinguishing features for identifying birds, and it’s precisely these key pieces of information that novice and expert birders alike must pay attention to whenever attempting to correctly identify wild birds.
As mentioned, crows and ravens are a couple of other species that are somewhat difficult to identify when the two species’ ranges overlap and observed either together in the field or separate. In the case of these species, vocalizations are definitely diagnostic features, though audible instead of visible. Hard to describe via written word, once the calls of each species are heard and compared, it’s a cinch to distinguish between the two species of lookalikes.
However, when voice won’t do the trick, then your eyes have to do the work that your ears cannot. Like downy and hairy woodpeckers, the size difference between crows and ravens, though not as stark as the difference between the two aforementioned woodpeckers, are notable—ravens are larger than crows are.
Another couple of diagnostic traits that will help you distinguish between crows and ravens are somewhat subtle, but different nonetheless. The tail of the raven, for example, when observed in flight, is broad and wedge-shaped. The crow’s tail is not wedge-shaped. Ravens soar more than crows do, too. Additionally, the beak of the raven is much heavier in appearance than that of the crow.
Feathers of each of the species are somewhat different as well. Whereas the crow has a more sleek appearance, up close one will note that the feathers of a raven are “rougher,” somewhat disheveled if you will, especially on the throat and breast, than that of the crow.
Other species that come to mind are the sharp-shinned and Cooper’s hawks. These two accipiters are already made difficult to quickly identify because each occur in similar habitats. And though the Cooper’s hawk is larger than the sharp-shinned hawk, the Cooper’s more rounded tail has a white-terminal band, whereas the sharp-shinned hawk’s tail is not rounded and lacks the white terminal band. Key differences, albeit subtle.
Certainly, the list goes on and on when it comes to correctly identifying similar looking species of wild birds in the field. By concentrating on traits that are unique to the species, one can quickly and accurately identify our feathered friends as we get and enjoy the great outdoors.