As there are over a hundred varieties of goldfish, coloration and physical characteristics vary greatly. The common goldfish has two sets of paired fins - the pectoral fins and pelvic fins, and three single fins- the dorsal, caudal, and anal fin. The head lacks scales. Goldfish have very large eyes and acute senses of smell and hearing. Instead of true teeth, goldfish have teeth in their throats which they use to crush food.
Although goldfishes originated in China, they have now spread worldwide in aquariums, ornamental pools, and into the wild.
In the wild, goldfish can be found in slow-moving, freshwater bodies of water. As with their close relative the carp, they thrive in slightly murky water. In captivity, an aquarium with live plants and a dirt bottom is ideal. Bi-weekly water changes are a good idea as a goldfish tank is hard to keep clean. Live plants must be replaced fairly regularly; goldfish enjoy eating them. Small pebbles are a suitable substitute for the pond-like bottom. Typically, goldfish will survive in water temperatures ranging from freezing to 30 degrees centegrade. Goldfish prefer a pH range of 6.5-8.5.
Although there is one report of a pet goldfish who lived 43 years, 25 years is a more reasonable maximum lifespan for a goldfish kept in a pond. In an aquarium, ten years is more likely. In the wild, lifespan is undoubtedly less.
In the wild, goldfish often travel in schools. They are not particularly aggressive fish.
In captivity, goldfish are commonly fed dried flake or pellet food. Good diet supplements include freeze dried Tubifex worms, mosquito larva, bloodworms, daphnia, brineshrimp, and vegetation such as boiled peas and lettuce.
Just about anything that eats fish would eat goldfish.
Introduced populations are due primarily to people releasing their pets into local waterways. Goldfish should not be released into ponds in the wild because they breed quickly and are capable of crowding out native fish species. They are considered pests in most places where they have been introduced.
Goldfish farming has become an industry of notable size. Millions of fish are bred each year and sold to aquarium shops for resale to fish enthusiasts. In North America there is a demand for goldfish to be used as bait by anglers. Pet shops often have feeder goldfish to sell to owners of carnivorous aquarium fish.
Goldfish are quite abundant.
Goldfish and common carp can hybridize.
Robin Street (author), University of Michigan-Ann Arbor.
Living in Australia, New Zealand, Tasmania, New Guinea and associated islands.
living in sub-Saharan Africa (south of 30 degrees north) and Madagascar.
living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.
living in the southern part of the New World. In other words, Central and South America.
living in the northern part of the Old World. In otherwords, Europe and Asia and northern Africa.
having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends.
an animal that mainly eats meat
uses smells or other chemicals to communicate
union of egg and spermatozoan
mainly lives in water that is not salty.
An animal that eats mainly plants or parts of plants.
referring to animal species that have been transported to and established populations in regions outside of their natural range, usually through human action.
offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).
having the capacity to move from one place to another.
specialized for swimming
the area in which the animal is naturally found, the region in which it is endemic.
an animal that mainly eats all kinds of things, including plants and animals
found in the oriental region of the world. In other words, India and southeast Asia.
reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.
the business of buying and selling animals for people to keep in their homes as pets.
breeding is confined to a particular season
reproduction that includes combining the genetic contribution of two individuals, a male and a female
associates with others of its species; forms social groups.
uses touch to communicate
that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).
A Fishkeeper's Guide to Fancy Goldfishes; Dr. Chris Andrews; Tetra Press; 1987.
The Audubon Society Field Guide to North American Fishes, Whales and Dolphins; 1993.
Froese, R., D. Pauly, eds.. 2002. "Species summary: Carrasius auratus" (On-line). Accessed 3 April 2002 at http://www.fishbase.org.