Identifying Butterflies in the Field
Now that you know how to find and observe butterflies, the next step is correctly identifying them. By using a few simple clues, you can learn the identity of an unknown butterfly. And, as your butterfly-watching skills increase, recognizing these clues will become second nature.
Size
One of the first and most obvious characteristics to note when you see a butterfly is its size. Although field guides often list wingspan for each species, such numbers are generally of little use in the field. It is easier to think of butterflies as small, medium or large.
Wing Color and Pattern
Butterflies come in a wide variety of colors and patterns. These distinctive wing features are the most valuable field marks and can be used to quickly identify different butterfly species. First, notice its overall ground color. Is the butterfly, for example, primarily yellow, black or white? Then try to spot any major wing patterns. Does the butterfly have distinct stripes, bands or eye spots? Finally, note the color, size and position of major markings and whether they occur on the upper surface (dorsal) or lower surface (ventral) of the wings.
Wing Shape
The shape or silhouette of a butterfly's wings also provides a valuable clue to its identity. Even if you can't discern any markings, wing shape will help you narrow down the family to which it belongs.
Flight Pattern and Behavior
Butterflies are active creatures. The way they fly, feed or even rest often differs a great deal among species. Thus flight pattern becomes a good identification clue. Does the butterfly flutter slowly with a weak, relaxed motion or whiz past with a strong, rapid flight? Does it fly low to the ground or soar far overhead? Does the butterfly bob up and down or periodically glide following a series of quick wing beats?
Range
Many butterfly species are found only in certain regions of the state. Before making a wild guess, consult a field guide range map and always start with the most probable identification.