Parts of the body and plumage
Here a description of the commonly used terms to describe birds' bodies and plumages. For more terms see the glossary. There is a separate page on birds' field of vision.
Below we show the most frequently used terms regarding a bird's body and plumage. This is best done by using a sideways (lateral) view.
Lateral view of an Olive-backed Oriole; for a description of the wing plumage see below
The wing plumage can be best seen when birds spread their wings. Here an example of the underwing feathers.
Magpie Goose stretching its wings
The wing plumage can be best seen when birds spread their wings. Here an example of the upperwing feathers.
Black-necked Stork hunting in shallow waters, casting a shadow with its outstretched wings
Some birds have prominent ceres, i.e. bare, fleshy parts just above their bills, in which the nostrils are located. The cere can sometimes used for identification purposes. Often the ceres of immature birds have different colours compared to those of adult bird. Or, as in the case shown below, the ceres of males and females differ.
Close-up portrait of a male Budgerigar, with its blue cere; females have fleshy-coloured ceres
Many birds have crests, consisting of a number of feathers that can be erected. Some crests are inconspicuous, giving a bird's head a helmet-shaped appearance, others are prominent and colourful, as e.g. the Sulphur-crested Cockatoo's.
Prominent, colourful crest of a Sulphur-crested Cockatoo
Four small feathers on a bird's remnant "thumb" are called alula. Often they are inconspicuous, but sometimes they can be seen quite clearly, as shown below.
Prominent alula on the wing of a White-bellied Sea-Eagle
Ventral view of a White-necked Heron banking to land; in the process the bird is maximising its lift and sideways stability, which requires the use of the alulas
Some birds have iridescent feathers in their wings. One special kind of such iridescence is a patch found on the upperwings of ducks, called "speculum".
Preening Australian Wood Duck displaying its speculum
Many bird species are "dimorphic", i.e. there are differences, e.g. between male and female, in size and/or plumage. The most notable dimorphisms are
- sexual dimorphism - when the male's plumage is different from the female's
- seasonal dimorphism - when a species has different breeding and non-breeding (eclipse) plumages