The Crossley ID Guide: Eastern Birds

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Richard Crossley – My Philosophy of Birding

SIZE

Somewhat surprisingly, perhaps, it turns out that we’re remarkably good at judging an individual’s height, in fact to within a 2% degree of accuracy on most occasions. The truth is that we spend most of our lives practicing. And practice makes perfect. So, not surprisingly, adults tend to be much better at judging height than children. We all judge relative size in birds to some degree, but often put little emphasis on this in the field. You should always focus on size and try to make as accurate an assessment of this feature as you can. Compare the bird you’re trying to identify with other nearby birds that you have already identified. With practice, you can become accomplished at determining size, which is critical since it is the least variable character that birds possess. Naturally we can also get this wrong, particularly when views are brief or distant, so the secret is to know your limits.

STRUCTURE / SHAPE

Along with size, structure and shape are fundamental to the identification of nearly all birds. Shape is remarkably consistent in individual species. Color and lighting have little or no effect in our determination of a bird’s shape and structure. Always try to describe a bird’s shape in language that makes sense to you. We each interpret or understand words such as’ fat’, ‘rounded’, ‘slim,’ and ‘long’ differently. While, as an author, I’m compelled to use these terms when describing a bird, ultimately you should create your own language and sense of scale to describe the same bird in terms that resonate with you.

BEHAVIOR

Learning the ‘personality’ of a bird is hugely important. This obviously takes longer to master than assessing a bird’s size and shape. Knowing the behavior of birds with which we are familiar is essential in the field. Behavior encompasses many aspects of identification, just as it does with our interrelationship with other humans. For instance, consider the type of habitat a species favors, how it moves, and whether it‘s a loner or gregarious. For example, a Sanderling is instantly recognizable when it relentlessly chases waves along the beach, a clinching identification feature regardless of color or shape.

PROBABILITY

We use probability in bird identification, sometimes more than we would credit. Does the bird usually or always occur in this location and in this habitat? When you go birding in an unfamiliar area you always start with this basic question, consciously or subconsciously. On your local patch you would naturally be more confident since you have built up experience of species’ occurrence and distribution. For instance, if you come from Massachussetts and find yourself birding on the Delaware River in New Jersey, you need to ask yourself: Is it Carolina or Black-capped Chickadee I’m likely to see here?

I estimate that I identify approximately 90% of the birds I see as silhouettes or simple black-and-white images — a flock of European Starlings swirling around, a Cooper’s Hawk chasing a Mourning Dove, a Northern Cardinal darting across a road, and a huge, dense flock of hirundines that will almost certainly be Tree Swallows. These are almost subconscious, reflex identifications built on years of careful field observation, and a just reward for learning to look.

COLOR

We love the myriad color of birds, and stunning photographs that capture them in all their astonishing beauty. Often we can’t help but be overwhelmed by a blast of color as we happen upon a stunning red-and-black Scarlet Tanager. The problem is that Scarlet Tanager (a bird that is consistent in size, shape, and behavior, and also spends most of its life in uniform habitat) changes its colors. In one season it is usually yellow, green, and black; but of course it has to change its feathers (molt), and so it has a period when it shows a complex combination of different feathers and therefore a changing pattern of colors. I won’t dwell on the challenge of learning plumages of females, juveniles, one-year-old males, and so forth! And there are other important factors that influence identification such as time of day, whether it is sunny or cloudy, position of the sun, amount of shade, feather wear and fading, aberrant (abnormal) plumage, and of course just the normal variation between individuals within the same species.

Of course, we are naturally attracted by color. Even so, always try to stick to identification basics: Is the bird in front of me the correct size and shape for the species I believe it to be? Does the species I’ve identified even occur here? Color can be extremely variable so it is important to focus less on the tone of the color itself and more on the overall pattern it creates, i.e. the relative colors of different parts of the body. For example, the shades of yellow in a Yellow Warbler are variable from bird to bird, but the lightest and darkest parts on each and every bird are remarkably consistent.

Ultimately, color is undeniably important in bird identification, and for beginners, in particular, it will almost always be the first feature to attract the eye. But the secret is to learn how to use color in combination with all of the other identification factors described above, and always to remember that most misidentifications are made because of a reliance on color as the key to successful field identification.