--- title: "Common Goldfish (Carassius auratus) | AnimalTracks.wiki" description: "The pond fish that makes alcohol to survive without oxygen and sees four colors, ultraviolet included." image: "https://animaltracks.wiki/images/animals/goldfish-1.webp" published: "2026-08-30" updated: "2026-09-29" --- # Common Goldfish (*Carassius auratus*) > **Status**: Checked against 5 sources, listed under Sources below. > **Tagline**: The pond fish that makes alcohol to survive without oxygen and sees four colors, ultraviolet included. > **Soundtrack Vibe**: 80s Retrowave & Synthwave // Home, "Resonance" > **Soundtrack Links**: [Spotify](https://open.spotify.com/track/2NHkwSwm6C6eAX3z6xm7Uy) | [YouTube](https://www.youtube.com/watch?v=8GW6sLrK40k) > **Vibe Match**: Home's "Resonance" rolls in slow synth swells that ripple outward, and a goldfish lives by ripples: its lateral line senses the currents and vibrations its schoolmates make while swimming. ## Biological Superpowers & Stats - **Taxonomy**: *Carassius auratus* - **Danger Level**: Low - **Conservation Status**: Least Concern ([IUCN Red List](https://doi.org/10.2305/iucn.uk.2013-1.rlts.t166083a1110472.en)) - **Superpower**: Makes ethanol to survive without oxygen, and sees four colors including ultraviolet - **Habitat**: Slow or still fresh water such as ponds, lakes, rivers and marshes, native to eastern Asia - **Diet**: Opportunistic omnivore: insects, eggs, plants, crustaceans and detritus - **Tags**: fish, freshwater, omnivore, domestic-pet ## Natural History & Behavior ## Brewing Alcohol Without Oxygen Without oxygen, most vertebrates die within minutes. Goldfish (*Carassius auratus*) are an exception. Fish of the genus *Carassius*, the crucian carp and the goldfish, survive prolonged periods without oxygen by producing ethanol as their metabolic end-product. Ethanol is the alcohol in drinks. > **Yeast chemistry in a fish** The trick rests on a pyruvate decarboxylase, an enzyme (a protein that speeds up a chemical reaction) analogous to the one in brewer's yeast and the first described in vertebrates. It works alongside a specialized alcohol dehydrogenase. ## Four Colors and a Motion Sensor Goldfish are tetrachromats, meaning they can see four colors: red, green, blue and ultraviolet. Along each side runs the lateral line, a row of sensory organs that helps them detect motion in the water around them. Herons, northern river otters and American bullfrogs can prey on goldfish. To defend against predators, goldfish form large groups called schools, and they warn each other with chemical signals that predators are nearby. ## A Bottom-Feeding Pond Bulldozer Goldfish originated in eastern Asia, including China, Hong Kong, Korea and Taiwan, and the range of the species expanded to most of the world. They tend to live in bodies of water with slow or no movement: ponds, lakes, rivers and marshes. Size depends on where the fish lives. Goldfish generally reach 15 to 20 centimeters and weigh 100 to 300 grams, though the USGS lists a maximum of 59 centimeters and 3.0 kilograms. In captivity, goldfish grow to about 2.5 to 15 centimeters, and wild goldfish often grow bigger than domesticated ones because their environment offers more resources and space to swim. Lifespan is typically 6 to 7 years, and it has been reported as long as 30 years. They are generalist omnivores that eat insects, eggs, plants and crustaceans. Goldfish feed at the water bottom, where they stir up sediment and increase turbidity, which is how cloudy the water is. They are tough: adult goldfish can survive water temperatures between 0 and 41 °C. Young goldfish hatch with dark, pigmented scales, which fade 2 to 3 months later. Females normally spawn 2000 to 4000 eggs at a time, and adult goldfish consume their own offspring. ## Frequently Asked Questions ### How long can a goldfish survive with no oxygen? It depends on the temperature. In one lab study, goldfish survived without oxygen for only a few hours at 20 °C, but for several days at 4 °C. Winter goldfish outlasted spring goldfish in the cold, and the study linked that to greater stores of glycogen, a stored fuel, in their livers. *(Source: [Walker & Johansen 1977]())* ### What happens when a pet goldfish ends up in the wild? It can breed and spread. The USGS lists goldfish as established or reported in all US states except Alaska, and says they can outcompete native fishes. Bright colors seldom carry on: the surviving offspring of colorful escapees are typically the natural olive-green. *(Source: [USGS Nonindigenous Aquatic Species database]())* ### What do wild goldfish actually eat? A study of one Quebec pond found that 45% of the gut contents were plants, 21% were insects such as midges and mosquitoes, and 4% were small crustaceans. Goldfish also eat earthworms and detritus, and pond experiments with caged goldfish suggest they eat amphibian eggs too. *(Source: [Animal Diversity Web, University of Michigan]())* ## Sources 1. [Huckstorf & Freyhof (2013). Carassius auratus. The IUCN Red List of Threatened Species 2013: e.T166083A1110472.]() 2. [Fagernes et al. (2017). Extreme anoxia tolerance in crucian carp and goldfish through neofunctionalization of duplicated genes creating a new ethanol-producing pyruvate decarboxylase pathway. Scientific Reports.]() 3. [Walker & Johansen (1977). Anaerobic metabolism in goldfish (Carassius auratus). Canadian Journal of Zoology.]() 4. [Carassius auratus (goldfish). Animal Diversity Web, University of Michigan.]() 5. [Carassius auratus (Linnaeus, 1758). USGS Nonindigenous Aquatic Species database.]() *Published August 30, 2026. Last updated September 29, 2026.* ```json { "@context": "https://schema.org", "@graph": [ { "@type": "Article", "@id": "https://animaltracks.wiki/animals/goldfish/#article", "isPartOf": { "@id": "https://animaltracks.wiki/#website" }, "headline": "Common Goldfish (Carassius auratus) | AnimalTracks.wiki", "description": "The pond fish that makes alcohol to survive without oxygen and sees four colors, ultraviolet included.", "image": [ "https://animaltracks.wiki/images/animals/goldfish-1.webp" ], "datePublished": "2026-08-30", "dateModified": "2026-09-29", "author": [ { "@type": "Organization", "name": "AnimalTracks.wiki Editorial Team", "url": "https://animaltracks.wiki" } ], "publisher": { "@type": "Organization", "@id": "https://animaltracks.wiki/#organization", "name": "AnimalTracks.wiki", "url": "https://animaltracks.wiki", "logo": { "@type": "ImageObject", "url": "https://animaltracks.wiki/icon-512.png" } }, "mainEntityOfPage": "https://animaltracks.wiki/animals/goldfish/", "citation": [ { "@type": "ScholarlyArticle", "name": "Carassius auratus. The IUCN Red List of Threatened Species 2013: e.T166083A1110472", "url": "https://doi.org/10.2305/iucn.uk.2013-1.rlts.t166083a1110472.en", "author": "Huckstorf & Freyhof", "datePublished": "2013", "isPartOf": { "@type": "Periodical", "name": "The IUCN Red List of Threatened Species" }, "identifier": "doi:10.2305/iucn.uk.2013-1.rlts.t166083a1110472.en" }, { "@type": "ScholarlyArticle", "name": "Extreme anoxia tolerance in crucian carp and goldfish through neofunctionalization of duplicated genes creating a new ethanol-producing pyruvate decarboxylase pathway", "url": "https://doi.org/10.1038/s41598-017-07385-4", "author": "Fagernes et al.", "datePublished": "2017", "isPartOf": { "@type": "Periodical", "name": "Scientific Reports" }, "identifier": "doi:10.1038/s41598-017-07385-4" }, { "@type": "ScholarlyArticle", "name": "Anaerobic metabolism in goldfish (Carassius auratus)", "url": "https://doi.org/10.1139/z77-170", "author": "Walker & Johansen", "datePublished": "1977", "isPartOf": { "@type": "Periodical", "name": "Canadian Journal of Zoology" }, "identifier": "doi:10.1139/z77-170" }, { "@type": "CreativeWork", "name": "Carassius auratus (goldfish)", "url": "https://animaldiversity.org/accounts/Carassius_auratus/", "publisher": { "@type": "Organization", "name": "Animal Diversity Web, University of Michigan" } }, { "@type": "CreativeWork", "name": "Carassius auratus (Linnaeus, 1758)", "url": "https://nas.er.usgs.gov/queries/FactSheet.aspx?SpeciesID=508", "publisher": { "@type": "Organization", "name": "USGS Nonindigenous Aquatic Species database" } } ], "about": { "@type": "Taxon", "name": "Common Goldfish", "scientificName": "Carassius auratus", "description": "Makes ethanol to survive without oxygen, and sees four colors including ultraviolet" } }, { "@type": "FAQPage", "@id": "https://animaltracks.wiki/animals/goldfish/#faq", "mainEntity": [ { "@type": "Question", "name": "How long can a goldfish survive with no oxygen?", "acceptedAnswer": { "@type": "Answer", "text": "It depends on the temperature. In one lab study, goldfish survived without oxygen for only a few hours at 20 °C, but for several days at 4 °C. Winter goldfish outlasted spring goldfish in the cold, and the study linked that to greater stores of glycogen, a stored fuel, in their livers.", "citation": { "@type": "ScholarlyArticle", "name": "Anaerobic metabolism in goldfish (Carassius auratus)", "url": "https://doi.org/10.1139/z77-170", "author": "Walker & Johansen", "datePublished": "1977", "isPartOf": { "@type": "Periodical", "name": "Canadian Journal of Zoology" }, "identifier": "doi:10.1139/z77-170" } } }, { "@type": "Question", "name": "What happens when a pet goldfish ends up in the wild?", "acceptedAnswer": { "@type": "Answer", "text": "It can breed and spread. The USGS lists goldfish as established or reported in all US states except Alaska, and says they can outcompete native fishes. Bright colors seldom carry on: the surviving offspring of colorful escapees are typically the natural olive-green.", "citation": { "@type": "CreativeWork", "name": "Carassius auratus (Linnaeus, 1758)", "url": "https://nas.er.usgs.gov/queries/FactSheet.aspx?SpeciesID=508", "publisher": { "@type": "Organization", "name": "USGS Nonindigenous Aquatic Species database" } } } }, { "@type": "Question", "name": "What do wild goldfish actually eat?", "acceptedAnswer": { "@type": "Answer", "text": "A study of one Quebec pond found that 45% of the gut contents were plants, 21% were insects such as midges and mosquitoes, and 4% were small crustaceans. Goldfish also eat earthworms and detritus, and pond experiments with caged goldfish suggest they eat amphibian eggs too.", "citation": { "@type": "CreativeWork", "name": "Carassius auratus (goldfish)", "url": "https://animaldiversity.org/accounts/Carassius_auratus/", "publisher": { "@type": "Organization", "name": "Animal Diversity Web, University of Michigan" } } } } ] }, { "@type": "MusicRecording", "name": "Resonance", "byArtist": { "@type": "MusicGroup", "name": "Home" }, "genre": "80s Retrowave & Synthwave", "url": "https://open.spotify.com/track/2NHkwSwm6C6eAX3z6xm7Uy" } ] } ```