Japanese quail

The Japanese quail (Coturnix japonica), also known as the coturnix quail, is a species of Old World quail found in East Asia. First considered a subspecies of the common quail, it is now considered as a separate species. The Japanese quail has played an active role in the lives of humanity since the 12th century, and continues to play major roles in industry and scientific research. Where it is found, the species is abundant across most of its range. Currently, there are a few true breeding mutations of the Japanese quail. The varieties currently found in the United States include Pharaoh, Italian, Manchurian, Tibetan, Rosetta, along with the following mutations: sex-linked brown, fee, roux, silver, andalusian, blue/blau, white winged pied, progressive pied, albino, calico, sparkly, as well as non-color mutations such as celadon.

The morphology of the Japanese quail differs depending on its stage in life. As chicks, both male and female individuals exhibit the same kind of plumage and coloring. Their heads are tawny in color, with small black patches littering the area above the beak. The wings and the back of the chick are a pale brown, the back also having four brown stripes running along its length. A pale yellow-brown stripe surrounded by smaller black stripes runs down the top of the head.

The plumage of the Japanese quail is sexually dimorphic, allowing for differing sexes to be distinguished from one another. Both male and female adults exhibit predominantly brown plumage. However, markings on the throat and breast, as well as the particular shade of brown of the plumage, can vary quite a bit. The breast feathers of females are littered with dark spots among generally pale feathers. Contrastingly, male breast feathers show off a uniform dark reddish-brown color that is devoid of any dark spots. This reddish-brown coloration also appears in the male cheek, while female cheek feathers are more cream colored. Some males also exhibit the formation of a white collar, whereas this does not occur in any female members of the species. It is important to note that while this coloration is very typical of wild populations of Coturnix japonica, domestication and selective breeding of this species has resulted in numerous different strains exhibiting a variety of plumage colors and patterns. Most of the strains are sexually dimorphic, however, there are some that can not be distinguished on the basis of plumage colouration, these include Texas A&M, English white, tuxedo and others .

Males tend to be smaller than females. Wild adults weigh between 90 and 100 grams while their domesticated counterparts typically weigh between 100 and 120 grams. However, weight among domesticated lines varies considerably, as commercial strains bred for meat production can weigh up to 300 grams.

Compared to the common quail the Japanese quail has darker upperparts with more contrast and is deeper rufous below. In the breeding season the male of the Japanese quail has distinctive rufous throat feathers. These are replaced by long pale feathers in the non-breeding season. This plumage feature is not observed in the common quail.

Some 28 different call types have been distinguished based on the circumstances in which they are used and the various behaviors that are exhibited during the call. The call types of the Japanese quail differ between male and female, the same stimulus resulting in differing vocalizations. Most of the calls used by this quail are present after five weeks of development; however, they remain relatively changeable until sexual maturity is reached. The typical crow of the Japanese quail is characterized by two short parts that precede a final, major trill.

Crowing of males has been observed to expedite the development of the female's gonads as those exposed to such crowing reach maturity much earlier that those who are not exposed to male vocalizations. Differences in crow patterns have been observed between males with mates and un-mated males.