Birds come in all sorts of eye-catching hues, which makes them easier to spot in busy backdrops. But colour isn’t always the best place to start when trying to identify a species. Bluebirds aren’t always blue, goldfinches aren’t always gold.
Scientists have grouped avians in dozens of families by their traits. Noting that a bird is gray isn’t as useful as recognising that it’s a gray owl, or a gray gull, or a gray sparrow-like bird. Hone it down to the family level, or to a group of families, and you’ll be halfway done.
A bird’s shape lets you place the bird in its right group. No two species share the same exact shape. Sandpipers differ in leg height, bill shape, neck length, and other elements of shape.
You can view a mystery bird in direct comparison to one you recognise. For instance, observe whether that bird is smaller than a robin or larger than a coot, etc.
Sometimes, we become so captivated by a bird’s good looks that we fail to notice what it’s actually doing. Is the bird hopping on the ground, climbing a tree trunk, wading in water, or flitting in the treetops? Is the bird all alone or part of a flock? These behaviours point to its identity.
Habitat is an excellent clue. You might see a Horned Lark on the ground in a plowed field and a Red-eyed Vireo in a forest treetop, but you’re very unlikely to see them trade places.
Birds are surprisingly predictable when it comes to timing — for many it’s a matter of life or death. For example, in United States, the easiest way to tell two rusty-capped sparrows apart is to glance at the calendar: Chipping Sparrow if it’s summer, American Tree Sparrow if it’s winter.
Trademarks such as a white ring around the eye, a pale stripe above it, body marked with round spots, lengthwise stripes, crosswise bars, white outer tail feathers, etc. will often pin down the species for you.
Most birders start with a visual identification and don’t really tackle birding by ear until later. But if your mystery bird is making some distinct sound, it’s worthwhile to make a note of it.