Tsaiya in fact comes in two colors: brown is the oldest that came from southern China, and white, bred from male muscovy and female tsaiya under strict protocols (officially known as Yilang white duck, 宜蘭白鴨). The brown tsaiya is raised mostly for its eggs, and white, for meat.
The red-faced black muscovy is the ferocious territorial kind. Its meat has a distinct flavor often used in the preparation of the ginger-duck-soup (薑母鴨) (below), a winter-time favorite for the Taiwanese. White muscocies were introduced from Australia in 1962, later also from the Netherlands and the US, and in 1984, France.
The lovely Peking duck, originally from northern China, was imported to Taiwan in 1954. Then there are the hybrids: male Peking + female tsaiya = kaiya (改鴨), and male muscovy + female tasiya = mule duck (土番鴨), bred for speedy maturation and increasing weights.
Consumption of duck eggs gradually shifted to chicken eggs after the introduction of large-scale chicken farming into Taiwan in 1961. These days, just like in the US, duck eggs are hard to find in supermarkets. And because of the elevated fatty contents of duck meat especially the skin, it has also fallen into disfavor for some consumers (even though there has been no evidence linking duck fats with cardiovascular diseases). The challenge now is how to breed ducks with lean meat.