An Introduction to Bird Colours

Colour is a great tool, but if you rely on it too much you might miss out on other key features when trying to identify a bird. Start with size, shape, and context clues before focusing on colour.

In the below images you’ll see that these birds are boldly black and white, but colour won’t be enough to help you find these birds in a guide book or if describing them to another person.

Bonaparte's Gull perched on a spruce tree. It's head is very black with black bill, and breast is white. — Bonaparte’s Gull

Black-necked Stilt standing in water. It is a shorebird with a long bill. Black back, black on the head, and a white breast. — Black-necked Stilt

Black and White warbler, is black and white streaked all over. Perched on a branch, singing. — Black and White Warbler

Colour can vary a lot! Some species will have different coloured plumage as they age, or throughout the seasons as they moult feathers. The males and females of some species may also look dramatically different if focusing solely on colour. And finally, colour can sometimes be hard to see. If the sun is behind a bird, it may appear much darker than it actually is.

We always recommend combining colour with the other identification tools you’ve already learned in this course.

Moult

Moulting is when birds shed their old feathers to make way for new ones. Moulting helps birds get rid of old or damaged feathers, so that they’ve always got feathers that are in good condition. Moulting can take a lot of energy, so birds will often molt when they’re not busy with breeding or migrating. Some species may molt several times per year, while others may only molt once.

For some species, moulting will help them transition between their non-breeding and breeding plumage which can be seen in the Snow Bunting images below. Snow Buntings nest in the high Arctic in the summertime, and when they finish breeding, they migrate south to the more densely populated regions in Canada. Unless you live in the very far north, you’re most likely to see Snow Buntings in their non-breeding plumage in the winter time.

Two images side by side. The first shows a Snow Bunting in non-breeding plumage. It has a creamy white breast and copper brown markings on the breast and face. The other Snow Bunting is in breeding plumage and is bright white with black wings, no copper colour. — Snow Buntings. Summer or breeding plumage is bright white (right), while they become more brown in their non-breeding plumage during the winter (left).

Age

Another major variation in colour within the same species could be the result of the age of the bird. Sometimes it’s very obvious when you’re looking at a chick. You’ll likely be able to tell by the size and shape, and from the way it interacts with the adult. However, once chicks move into their “awkward teenage” phase, they can be much trickier to identify. These birds are referred to as immature, which is a term that describes birds that have not reached sexual maturity yet. You may also hear the terms fledgling, for birds that have recently started to fly, or juvenile, for birds that are a little older than fledglings.

A Common Loon family on the water. Two adults and two chicks. — Common Loons feeding chicks. Water birds are often easy to see with their young.

Juvenile birds are typically able to fly and are independent, and are often a similar size and shape as adults. They have not developed the bold colours that are typical of breeding adults because they haven’t reached that stage yet. They may be more streaky or spotted, or may have duller colours, sometimes resulting in them being mistaken for females. This immature stage can last for a single year or a few years, depending on the species.

When you’re just starting to identify birds, it’s really helpful to know about these life stages, but you don’t need to focus on them too much. If you see a bird that looks familiar, but isn’t quite what you expect, it could simply be an immature bird. You’ll be more likely to see these individuals later in the summer.

Two images, well described by the caption. — Notice how the adult American Robin on the left has a bold orange breast, while the chicks that it is feeding are very speckled. On the right we see a robin that is the same size and shape as an adult, but is very speckled – this is an immature bird.

Gull species take 2-5 years to reach maturity. The next time you see a flock of gulls, try to spot the wide variety of colour patterns. These may all be part of the same species but could be different ages. You’ll have to look for additional clues to identify their species, such as the size and shape, markers on the bill, and you’ll want to also consider which gull species may live in your area.

Two images. The juvenile gull is very mottled, white the adult gull has a crisp clean white plumage. — The Ring-billed Gull on the left has mottled brown and white plumage that is typical of a juvenile, while the bird on the right has the clean white plumage of an adult.

Sexual Dimorphism

A third factor that could make birds of the same species look different from each other is sexual dimorphism. In some species the male and female can look dramatically different. Male’s might have flashier plumage during the breeding season, size may vary between the sexes, and there may even be different features or shapes to consider.

On the flip side, some bird species will look the same regardless of sex, such as the Black-capped Chickadee, Mourning Dove, or House Wren.

Bufflehead. The males are boldly white and black, while the females are a duller and dark colour overall, with a distinct white patch on the cheek.

Wood Duck. The male has very intricate plumage with a green crest and bold white markings on the face. The female is more drab, brown overall, with white around the eye.

House Finch. The males are rosy red on the face and breast, while the females lack the red colour. Both have streaking on the underparts.

Evening Grosbeak. Males have prominent yellow, white and black colours. Females are mostly gray with white and black wings, and a tinge of yellow near the face.

As you’ll see above, a wetland is a great place to start looking for sexual dimorphism as many waterfowl species exhibit this trait. You will also notice this at your bird feeders with species like the Pine Grosbeak, Northern Cardinal, House Sparrow, American Goldfinch, or Baltimore Oriole – to name a few.