(noun) A type of plumage coloration that features dark upperparts and pale underparts. This provides dark coloration to the parts of the bird that are normally exposed to the most light, and light coloration to the parts that are frequently exposed to shadows. This pattern breaks up the outline of the bird to any predator, helping with camouflage to keep the bird protected. Even when viewed from the side, countershading helps disrupt the bird's outline and keep it concealed. The exact colors in countershading can vary greatly and may include shades of brown, gray and black above with white, buff and light gray below.
Many different types of birds have countershading patterns in their plumage, but this type of coloration is most noticeable with birds that are regularly viewed from both above and below, making the plumage pattern more effective for camouflage from every angle. Shorebirds, waterfowl, penguins, seabirds, diurnal raptors and swallows all exhibit countershading to varying degrees.
In addition to birds, countershading is also a prominent coloration pattern for many fish, insects, squirrels, deer and other animals that may regularly be viewed from different angles, particularly from both above and below.
Photo – Spotted Sandpiper © Mike Baird, flickr.bairdphotos.com
KOWN-terr-SHAY-deeeng
Thayer's Law
Counter-Shading, Counter Shading


