Principles of Genetics and Breeding

14.1.11. The Goldfish

The goldfish has long been the most domesticated fish and now seems to be better adapted to confinement than to a ‘free life’. The wild goldfish is native to China, the southern Amur River basin and Korea. It was introduced to Japan from China between 1502 and 1620.

Domesticated goldfish had to come by boat from China and must have been very expensive. As such their owners would guard them from release into natural waters. Invasions from aquaria and garden pools into all suitable habitats around the world came later.

Purnell’s Encyclopedia of Animal Life (Burton, 1969) makes the following statement with regard to goldfish: ‘The more fancy breeds of goldfish are freaks, no matter how attractive some of them may look. To recite their names is enough to make this point: veil tail, egg fish, telescope, calico, celestial, lion head, tumbler, comet or meteor and pearl scale. There are also the water bubble eye, blue fish, brown fish, brocade, pompon and fantail and many others. Some breeds are monstrosities rather than freaks’.

The creation of ‘monstrosities’ in shape, in addition to colour aberrations, was closely related to the keeping of indoor aquaria, which became a very popular hobby after 1548. The goldfish became the pet of the masses, a popular pastime in many homes everywhere.

Unintentional artificial selection and crossbreeding played an enormous role in the production of more and more bizarre individuals. For example, most of the future red goldfish appear black when young and so severe culling had to be applied several times in succession to raise a few ornamental individuals. So, in the short span of 97 years, between 1547 and 1643, at the end of the Ming Dynasty, new varieties were produced with an increasing degree of variation.

Varieties such as golden helmet, golden saddle, stork’s pearl, brocaded back, seven stars, red head-and-tail, purple eyes, snow eyes, the three tails, four tail, nine tail, bulging eyes, the bicaudal and the dragon eye have became quite common.

The double tail was first mentioned in 1579 and the dragon eye in 1592; by 1596 the short body was already in existence, the dragon back without the dorsal fin appeared by 1726, and the duck’s-egg fish by 1780.

By 1848 goldfish breeders in China were already using deliberate artificial selection and obtained the lion-head, goose head and the narial bouquet goldfish.