Why Do We Hate Carp But Love Koi?

Why do we kill carp but treasure koi fish, when they're basically the same animal? In this video, we look at how one fish became one of the most hated invasive species on Earth and one of the most expensive pets money can buy. Carp were farmed for thousands of years, from ancient China to medieval European monasteries. In 1877, the U.S. government shipped them across America as the "fish of the future," and they turned into an invasive disaster. Today, Utah removes carp by the millions of pounds, and Australia is weighing a deadly virus to wipe them out. Meanwhile, rice farmers in Niigata, Japan bred random color mutations into koi, and one koi, S Legend, sold for about $1.8 million. We cover koi vs carp, how koi breeding works, why koi herpesvirus connects both stories, and what happens when pet koi are released into the wild. In New Zealand, the result is an invasive pest literally called "koi carp." If you like animal science, invasive species stories, and weird nature facts, subscribe to Quanta for more videos like this. Timestamps: 00:00 Same fish, completely different treatment 00:57 The toughest fish on Earth 02:11 How America spread carp everywhere 04:08 Australia's carp virus plan 04:47 How koi were born in Japan 06:18 The $1.8 million koi 08:35 What happens when koi go wild References: Balon, E. K. (1995). "Origin and domestication of the wild carp, Cyprinus carpio: from Roman gourmets to the swimming flowers." Aquaculture, 129, 3–48. This covers carp history, Roman and monastery ponds, and koi domestication. USGS Nonindigenous Aquatic Species Database, "Cyprinus carpio (Common Carp)" fact sheet. This covers U.S. introduction history and ecological impacts. Hedrick, R. P., et al. (2000). "A herpesvirus associated with mass mortality of juvenile and adult koi." Journal of Aquatic Animal Health, 12, 44–57. This covers the early identification of koi herpesvirus. Australia's National Carp Control Plan (Fisheries Research and Development Corporation). This covers the CyHV-3 biocontrol proposal, carp in the Murray-Darling Basin, and risks from fish die-off. June Sucker Recovery Implementation Program / Utah Division of Wildlife Resources. This covers the Utah Lake carp removal program. New Zealand Department of Conservation, "Koi carp" pest fish page. This covers the Waikato spread, the pest classification, and the ban on release. News coverage of the 2018 "S Legend" Kohaku sale (~¥203 million) from Sakai Fish Farm. Yang Yu Jing (Treatise on Fish Breeding), traditionally attributed to Fan Li, around the 5th century BC.