---
title: "What the sources say about the Koi | AnimalTracks.wiki"
description: "53 claims from the Koi profile, each beside the words of the source that backs it."
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---

# What the sources say about the Koi (*Cyprinus rubrofuscus*)

> 53 claims from the Koi profile, each beside the words of the source that backs it. A "..." marks a cut in a quote and [brackets] an insertion.

Profile: [Koi](https://animaltracks.wiki/animals/koi/)

## Bogutskaya & Huckstorf (2022). Cyprinus rubrofuscus. The IUCN Red List of Threatened Species 2022: e.T166052A159637283.

https://doi.org/10.2305/iucn.uk.2022-1.rlts.t166052a159637283.en

| The page says | The source says |
| :--- | :--- |
| Least Concern | IUCN Red List category: Least Concern (LC). (note: Assessment is of the wild species Cyprinus rubrofuscus (IUCN taxon 166052), not of the domestic koi varieties; category read through GBIF's copy of the Red List.) |
| That rating describes the wild fish, not the pond varieties. | Cyprinus rubrofuscus Lacepède, 1803, IUCN taxon 166052 (note: The assessment is of the species Cyprinus rubrofuscus; SDZWA calls koi ornamental varieties of domesticated common carp.) |
| which FishBase and the Red List treat as a wild species | Cyprinus rubrofuscus Lacepède, 1803, IUCN taxon 166052 |

## Fife-Cook & Franks (2021). Koi (Cyprinus rubrofuscus) Seek Out Tactile Interaction with Humans: General Patterns and Individual Differences. Animals.

https://doi.org/10.3390/ani11030706

| The page says | The source says |
| :--- | :--- |
| in one study, sought out a human hand | koi spent more time than expected in close proximity to the human and even sought out physical contact |
| In one study, sought out a human hand for touch even after a full meal | The koi showed interest in pursuing physical interaction even after feeding to satiation |
| A 2021 study names them Cyprinus rubrofuscus | Koi ( Cyprinus rubrofuscus ) Seek Out Tactile Interaction with Humans: General Patterns and Individual Differences
Fife-Cook Isabel 1 Franks Becca 1 * Irvine Leslie Academic Editor 1 1 Department of Environmental Studies, New York University, New York, NY 10003, USA; ifc219@nyu.edu * Correspondence: krf205@nyu.edu
5 3 2021 (note: 2021 is the paper's publication year (MDPI Animals 2021, 11, 706). The Red List assessment is of Cyprinus rubrofuscus, see the IUCN status claim.) |
| a researcher offered a submerged hand to seven adult koi | the fish were regularly provided with the opportunity to engage with the researcher’s submerged hand |
| each between 40 and 60 centimeters long | Bessie M 40–45 cm ... Gabriel M 55–60 cm (note: Table 1 lists the seven adult koi from 40-45 cm (Bessie) to 55-60 cm (Dominick, Gabriel).) |
| without forcing contact | but were not forced to interact with the researcher |
| at an aquaponics learning center in Brooklyn | aquaponics learning center located in Brooklyn, NY |
| The koi spent more time than expected within reach of the researcher | koi spent more time than expected within reach of the researcher |
| they started the touching themselves by mouthing, brushing and bumping the hand | initiated by the fish (mouthing, brushing, bumping, etc.) |
| Some did this often and others rarely. | with some frequently engaging in tactile interaction and others only periodically or rarely doing so |
| The koi stayed interested even after being fed to satiation (full), which the authors say suggests the interest may not be about food. | The koi showed interest in pursuing physical interaction even after feeding to satiation, suggesting that they may be motivated to seek physical interaction for reasons unrelated to food seeking behavior |
| the fish chose to stay near a researcher's submerged hand | koi spent more time than expected within reach of the researcher during both T1 ( p < 0.02) and T2 ( p < 0.03) |
| How often they did so varied a lot from fish to fish. | individual fish displayed unique interaction patterns, with some frequently engaging in tactile interaction and others only periodically or rarely doing so |
| seven adult koi | seven adult and two juvenile koi |
| touched it of their own accord | initiated by the fish (mouthing, brushing, bumping, etc.) |
| a Brooklyn aquaponics center | aquaponics learning center located in Brooklyn, NY |
| whose name one koi study uses | Koi ( Cyprinus rubrofuscus ) Seek Out Tactile Interaction with Humans |
| In a study published in 2021 | © 2021 by the authors. |

## Koi (Cyprinus carpio). San Diego Zoo Wildlife Alliance.

https://animals.sandiegozoo.org/animals/koi

| The page says | The source says |
| :--- | :--- |
| A pet carp bred into over 100 colour varieties | There are over 100 varieties of koi |
| Outdoor ponds and water gardens | their true value is in outdoor ponds and water gardens |
| Mostly plant foods such as rice and corn, plus live shrimp and their own young | They are mostly vegetarians—rice and corn are among koi's favorite foods—but they will also eat live shrimp and even their own young |
| Koi are ornamental varieties of domesticated common carp, first bred in Japan. | Koi are ornamental varieties of domesticated common carp that originated in Japan. |
| Without a good filtration system in their pond, koi would poison themselves, as they excrete ammonia. | Without a good filtration system in their pond, koi would poison themselves, as they excrete ammonia. |
| Keepers put them in outdoor ponds with very clean, oxygenated water and plenty of shade. | They are kept for decorative purposes in outdoor ponds with very clean, oxygenated water and plenty of shade |
| The shade matters: koi can get sunburned. | plenty of shade (the fish are susceptible to sunburn!) |
| Chinese farmers raised carp in rice paddies for food in the 1600s, and the practice spread to Japan. | In the 1600s, Chinese farmed carp in rice paddies as a food source, a practice that traveled to Japan. |
| There, people spotted odd colors in some of the carp and bred them. | The Japanese noticed odd color variations in some of the carp and bred them. |
| Today there are over 100 koi varieties, in red, white, black, yellow, brown, gray and green, and many combinations of those. | There are over 100 varieties of koi, which can be red, white, black, yellow, brown, gray, and green, and many combinations thereof. |
| Koi eat mostly plants, with rice and corn among their favorite foods. | They are mostly vegetarians—rice and corn are among koi's favorite foods |
| They will also eat live shrimp and even their own young, called fry, before the little fish's colors come in. | they will also eat live shrimp and even their own young, called "fry," before the little fish's coloration comes in |
| The San Diego Zoo files them under Cyprinus carpio, the common carp. | Koi are ornamental varieties of domesticated common carp |
| For koi, the zoo gives a maximum length of about 3 feet (91 centimeters) | Length: About 3 feet (91 centimeters) maximum (note: Maximum length, for koi as filed under Cyprinus carpio by the zoo.) |
| an average weight of about 35 pounds (16 kilograms) | Weight: About 35 pounds (16 kilograms), on average |
| koi typically live 25 to 35 years if cared for properly | Typically 25 to 35 years if cared for properly |
| Koi, by contrast, are kept as pets on 6 out of 7 continents, the zoo says. | Today, they are kept as pets on 6 out of 7 continents. |
| the zoo says koi are not endangered | They are not endangered. |
| koi can be taught to eat from a person's hand | Koi can be taught to eat from a person's hand. |
| Usually 25 to 35 years with good care, according to the San Diego Zoo. | Typically 25 to 35 years if cared for properly |
| Their own waste can kill them. | koi would poison themselves, as they excrete ammonia |
| bred from odd colour variations | The Japanese noticed odd color variations in some of the carp and bred them. (note: vibe.reason (#1238)) |
| into over 100 varieties in red, white, black, yellow, brown, gray and green | There are over 100 varieties of koi, which can be red, white, black, yellow, brown, gray, and green, and many combinations thereof. (note: vibe.reason (#1238)) |
| weightKg: 16 | Weight: About 35 pounds (16 kilograms), on average (note: battleStats.weightKg, typical adult (#1165)) |

## Cyprinus rubrofuscus Lacepède, 1803. FishBase.

https://www.fishbase.se/summary/Cyprinus-rubrofuscus.html

| The page says | The source says |
| :--- | :--- |
| the wild species lives in Laos, Viet Nam and China | Asia: Laos, Viet Nam and China |
| FishBase lists a maximum length of 28 centimeters (standard length) | Max length : 28.0 cm SL male/unsexed (note: Wild Cyprinus rubrofuscus; SL is standard length.) |
| places the species in Asia: Laos, Viet Nam and China, from the Amur to Red River drainages | Asia: Laos, Viet Nam and China (Ref. 43281 ). Amur to Red River drainages |
| The Red List rates the wild species Least Concern, assessed in 2020 | Least Concern (LC) ; Date assessed: 20 March 2020 |
| as Least Concern, assessed on 20 March 2020 | Least Concern (LC) ; Date assessed: 20 March 2020 |
| the wild carp of Laos, Viet Nam and China | Asia: Laos, Viet Nam and China |
| dangerLevel: Low | Threat to humans
Harmless (note: stats.dangerLevel (#1165); FishBase page is the wild species) |

## AnAge entry for Cyprinus carpio. AnAge: The Animal Ageing and Longevity Database, Build 15, Human Ageing Genomic Resources.

https://genomics.senescence.info/species/entry.php?species=Cyprinus_carpio

| The page says | The source says |
| :--- | :--- |
| AnAge lists a maximum longevity of 47 years in captivity | Maximum longevity 47 years (captivity) (note: Common carp, Cyprinus carpio, not koi specifically.) |