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<br />22 Foreign Nonindigenous Carps and Minnows (Cyprinidae) in the U.S.-A Guide to their Identification
<br />
<br />Ecology
<br />
<br />Goldfish may reach 59 em TL and up to 3.0 kg
<br />(IGFA, 2001); however, they generally reach only 15-
<br />20 cm TL and weigh 100-300 g (Szczerbowski, 2001).
<br />Lifespan is typically 6-7 years, but has been reported as
<br />long as 30 years (Essing, 1898, in Carlander, 1969).
<br />Typical habitat includes the quiet backwaters of
<br />streams and pools, especially those with submerged
<br />aquatic vegetation (Hensley and Courtenay, 1980;
<br />Trautman, 1981; Robison and Buchanan, 1988).
<br />The Goldfish is tolerant of high levels ofturbidity
<br />(Wallen, 1951), temperature fluctuations (reviewed
<br />by Spotila and others, 1979), and low levels of
<br />dissolved oxygen (Zhadin and Gerd, 1963; Walker
<br />and Johansen, 1977). Laboratory results reported pH
<br />tolerance levels between 4.5-10.5, and a preference
<br />for pH levels between 5.5-7.0 (Szczerbowski, 2001).
<br />Although laboratory tests suggested that eggs and
<br />fry are not particularly salinity tolerant (Murai and
<br />Andrews, 1977), the Goldfish is reported to live in
<br />salt lakes on the coast of the Black Sea and to inhabit
<br />the floodplain of the Ob delta in Russia (Zhadin and
<br />Gerd, 1963). The Goldfish has been captured in waters
<br />with salinities as high as 17 parts per thousand (ppt)
<br />(Schwartz, 1964), although studies have shown an
<br />inability to withstand long exposures exceeding 15 ppt
<br />(Lockley, 1957). Adults thrive equally well in salini-
<br />ties between 0-6 ppt (Canagaratnam, 1959), and can
<br />survive water temperatures between 0-41 oC (Carlander,
<br />1969; ~oyle, 2002). Additionally, the species is more
<br />tolerant of aquatic pollution than most native North
<br />American fishes (Robison and Buchanan, 1988).
<br />The ominvorous diet includes planktonic crus-
<br />taceans, phytoplankton, insect larvae, fish eggs
<br />and fry, benthic vegetation, and detritus (Scott
<br />
<br />and Crossman, 1973; Hensley and Courtenay,
<br />1980; Robison & Buchanan, 1988; Moyle, 2002).
<br />Foraging Goldfish may create high levels of turbid-
<br />ity, which can result in the decline of aquatic
<br />vegetation (Richardson and others, 1995).
<br />
<br />Native Distribution
<br />
<br />The Goldfish is native to Eastern and Central Asia,
<br />including China, Russia, Korea, and possibly Japan
<br />and Taiwan (Wheeler, 1978; Szczerbowski, 2001). It
<br />may also be native to parts of eastern Europe (Raicu
<br />and others, 1981); however, widespread transfer over
<br />several centuries has obscured the natural distribution.
<br />
<br />U.S. Introductions
<br />
<br />The Goldfish is thought to be the first foreign
<br />fish species introduced to North America (De Kay
<br />1842; Courtenay and others, 1984; Fuller and others,
<br />1999). The first recorded releases in the U.S. prob-
<br />ably occurred during the late 1600s (De Kay, 1842;
<br />Courtenay & Stauffer, 1990), and the species is now
<br />reported in all states except Alaska (Fuller and others,
<br />1999). The Goldfish is raised for the aquarium trade
<br />(as both an ornamental and live food), as bait for
<br />anglers, and as forage in fish hatcheries. Bait dealers
<br />in coastal regions along the Gulf of Mexico some-
<br />times sell Goldfish under the names "Black Saltys"
<br />or "Black Salties." Although not typically eaten by
<br />humans in the U.S., it is a valued food fish in China.
<br />Escapes from aquaculture facilities and deliberate
<br />releases have resulted in the establishment of local-
<br />ized populations across much of the U.S. The exact
<br />distribution is difficult to ascertain, as introductions
<br />continue intermittently throughout much of the country.
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