Pacu () is a common name used to refer to several species of omnivorous

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the southe ...

n freshwater

serrasalmid The Serrasalmidae (serrasalmids) are a family of characiform fishes, recently elevated to family status. It includes more than 90 species. The name means "serrated salmon family", which refers to the serrated keel running along the belly of these ...

fish that are related to the

piranha A piranha or piraña (, , or ; or , ) is one of a number of freshwater fish in the family Serrasalmidae, or the subfamily Serrasalminae within the tetra family, Characidae in order Characiformes. These fish inhabit South American rivers, ...

. Pacu and piranha do not have similar teeth, the main difference being jaw alignment; piranha have pointed, razor-sharp teeth in a pronounced

underbite In orthodontics, a malocclusion is a misalignment or incorrect relation between the teeth of the upper and lower dental arches when they approach each other as the jaws close. The English-language term dates from 1864; Edward Angle (1855-1930), ...

, whereas pacu have squarer, straighter teeth and a less severe underbite, or a slight

overbite Overbite is the extent of vertical ( superior-inferior) overlap of the maxillary central incisors over the mandibular central incisors, measured relative to the incisal ridges. The term overbite does not refer to a specific condition, nor is ...

. Pacu, unlike piranha, mainly feed on plant material and not flesh or

scales Scale or scales may refer to: Mathematics * Scale (descriptive set theory), an object defined on a set of points * Scale (ratio), the ratio of a linear dimension of a model to the corresponding dimension of the original * Scale factor, a number w ...

. Additionally, the pacu can reach much larger sizes than piranha, at up to in total length and in weight.

Name

The common name ''pacu'' is generally applied to fish classified under the below listed

genera Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nomenclat ...

. Among these, several genera contain species where commonly used English names include the word ''pacu'', as listed. *''

Colossoma The tambaqui (''Colossoma macropomum'') is a large species of freshwater fish in the family Serrasalmidae. It is native to tropical South America, but kept in aquaculture and introduced elsewhere. It is also known by the names black pacu, blac ...

'' – black pacu, black-finned pacu, giant pacu *''

Metynnis ''Metynnis'' is a genus of serrasalmid fish from tropical and subtropical South America. They are herbivorous or omnivorous, and inhabit a wide range of freshwater habitats, ranging from rivers and streams (both fast- and slow-flowing), to flood ...

'' *''

Mylesinus ''Mylesinus'' is a genus of serrasalmids from South America, where found in the eastern Amazon, Essequibo and Orinoco basins. They are rheophilic, typically found at rapids and mainly feed on Podostemaceae plants. Because of their habitat prefe ...

'' (''

Myloplus ''Myloplus'' is a genus of freshwater fish in the family Serrasalmidae found in tropical and subtropical South America, where they inhabit rivers and streams (both slow and fast-flowing). They are primarily herbivores, but also take some animal ...

'') *''

Mylossoma ''Mylossoma'' is a genus of serrasalmids from tropical and subtropical South America, including the basins of the Amazon, Orinoco, Lake Maracaibo and Paraguay- Paraná. These common fish are found both in main river sections and floodplains. T ...

'' *''

Ossubtus ''Ossubtus'' is a genus of fish in the family Serrasalmidae. It contains a single species, ''Ossubtus xinguense'', the parrot pacu or eaglebeak pacu, The species is endemic to rapids in the Xingu River basin in the Brazilian Amazon.Andrade, M.C., ...

'' – parrot pacu, eaglebeak pacu *''

Piaractus ''Piaractus'' is a genus of large serrasalmid from South America. The two traditionally recognized species of ''Piaractus'' are very similar in appearance and were formerly included in the genus ''Colossoma'', which currently only contains anothe ...

'' – red-bellied pacu, small-scaled pacu *''

Tometes ''Tometes'' is a genus of fish in the family Serrasalmidae found in fast-flowing rivers in northern South America. Adults of all seven species in this genus are phytophagous, feeding primarily on aquatic plants in the family Podostemaceae. The ...

'' *''

Utiaritichthys ''Utiaritichthys'' is a genus of serrasalmid fish found in the Amazon and Orinoco basins in tropical South America. The adults are typically found in rapidly flowing water where they feed on aquatic plants in the family Podostemaceae and filame ...

'' Each of these groups contains one or more separate species. For example, the fish often found in pet stores known as the black pacu and red-bellied pacu typically belong to the species ''

Colossoma macropomum The tambaqui (''Colossoma macropomum'') is a large species of freshwater fish in the family Serrasalmidae. It is native to tropical South America, but kept in aquaculture and introduced elsewhere. It is also known by the names black pacu, black- ...

'' and ''

Piaractus brachypomus ''Piaractus brachypomus'', the pirapitinga, is a large species of pacu, a close relative of piranhas and silver dollars, in the serrasalmid family.Nico, L.; P. Fuller; and M. Neilson (22 October 2013)Piaractus brachypomus.USGS Nonindigenous Aqua ...

'', respectively.SeriouslyFish
Piaractus brachypomus.
Retrieved 13 March 2017.SeriouslyFish
Colossoma macropomum.
Retrieved 13 March 2017. A species popular among

fish farm upright=1.3, Salmon farming in the sea (mariculture) at Loch Ainort, Isle of Skye">mariculture.html" ;"title="Salmon farming in the sea (mariculture">Salmon farming in the sea (mariculture) at Loch Ainort, Isle of Skye, Scotland Fish farming or ...

ers is ''

Piaractus mesopotamicus ''Piaractus mesopotamicus'', the small-scaled pacu, Paraná River pacu or simply pacu (a name shared with other species), is a South American ray-finned fish that is native to the Paraguay- Paraná River basin,Nico, L.; and B. Loftus (7 October ...

'', also known as Paraná River pacu or small-scaled pacu. Pacu is a term of

Tupi Tupi may refer to: * Tupi people of Brazil * Tupi or Tupian languages, spoken in South America ** Tupi language, an extinct Tupian language spoken by the Tupi people * Tupi oil field off the coast of Brazil * Tupi Paulista, a Brazilian municipalit ...

Guaraní Guarani, Guaraní or Guarany may refer to Ethnography * Guaraní people, an indigenous people from South America's interior (Brazil, Argentina, Paraguay and Bolivia) * Guaraní language, or Paraguayan Guarani, an official language of Paraguay * ...

origin. When the large fish of the genus ''Colossoma'' entered the aquarium trade in the U.S. and other countries, they were labeled pacu. In the

Brazilian Amazon Brazilian commonly refers to: * Something of, from or relating to Brazil * Brazilian Portuguese, the dialect of the Portuguese language used mostly in Brazil * Brazilians, the people (citizens) of Brazil, or of Brazilian descent Brazilian may also ...

, the term ''pacu'' is generally reserved to smaller and medium-sized fish in the ''Metynnis'', ''Mylossoma'', ''Mylesinus'' and ''Myleus'' genera. ''Colossoma macropomum'' are known as tambaqui, whereas ''Piaractus brachypomus'' is known as pirapitinga. In Peru, both of the species (''Colossoma macropomum'' and ''Piaractus brachypomum'') are called pacú and gamitana. ''Piaractus mesopotamicus'' of the Paraná-

Paraguay Paraguay (; ), officially the Republic of Paraguay ( es, República del Paraguay, links=no; gn, Tavakuairetã Paraguái, links=si), is a landlocked country in South America. It is bordered by Argentina to the south and southwest, Brazil to th ...

basin is also called pacú in Paraguay and Argentina.

Classification

Pacu, along with their piranha relatives, are a characin fish, meaning a kind of

tetra Terrestrial Trunked Radio (TETRA; formerly known as Trans-European Trunked Radio), a European standard for a trunked radio system, is a professional mobile radio and two-way transceiver specification. TETRA was specifically designed for use by go ...

, belonging to the

Characiformes Characiformes is an order of ray-finned fish, comprising the characins and their allies. Grouped in 18 recognized families, more than 2000 different species are described, including the well-known piranha and tetras.; Buckup P.A.: "Relationshi ...

order. The ongoing classification of these fish is difficult and often contentious, with

ichthyologist Ichthyology is the branch of zoology devoted to the study of fish, including bony fish ( Osteichthyes), cartilaginous fish (Chondrichthyes), and jawless fish (Agnatha). According to FishBase, 33,400 species of fish had been described as of Octobe ...

s basing ranks according to characteristics that may overlap irregularly. DNA research sometimes confounds rather than clarifies species ranking. Ultimately, classifications can be rather arbitrary. Pacu, along with piranha, are currently further classified into the family

Serrasalmidae The Serrasalmidae (serrasalmids) are a family of characiform fishes, recently elevated to family status. It includes more than 90 species. The name means "serrated salmon family", which refers to the serrated keel running along the belly of these ...

(formerly a subfamily of

Characidae Characidae, the characids or characins is a family of freshwater subtropical and tropical fish, belonging to the order Characiformes. The name "characins" is the historical one, but scientists today tend to prefer "characids" to reflect their st ...

). Serrasalmidae means "serrated salmon family" and refers to the serrated keel running along the belly of these fish. However, dental characteristics and feeding habits further separate the two groups from each other.

Native distribution and habitat

Pacus are native to tropical and

subtropical The subtropical zones or subtropics are geographical zone, geographical and Köppen climate classification, climate zones to the Northern Hemisphere, north and Southern Hemisphere, south of the tropics. Geographically part of the Geographical z ...

South America. They inhabit rivers, lakes,

floodplain A floodplain or flood plain or bottomlands is an area of land adjacent to a river which stretches from the banks of its channel to the base of the enclosing valley walls, and which experiences flooding during periods of high discharge.Goudi ...

s and

flooded forest Freshwater swamp forests, or flooded forests, are forests which are inundated with freshwater, either permanently or seasonally. They normally occur along the lower reaches of rivers and around freshwater lakes. Freshwater swamp forests are found ...

s in the

Amazon Amazon most often refers to: * Amazons, a tribe of female warriors in Greek mythology * Amazon rainforest, a rainforest covering most of the Amazon basin * Amazon River, in South America * Amazon (company), an American multinational technology c ...

Orinoco The Orinoco () is one of the longest rivers in South America at . Its drainage basin, sometimes known as the Orinoquia, covers , with 76.3 percent of it in Venezuela and the remainder in Colombia. It is the fourth largest river in the wor ...

São Francisco River The São Francisco River (, ) is a large river in Brazil. With a length of , it is the longest river that runs entirely in Brazilian territory, and the fourth longest in South America and overall in Brazil (after the Amazon, the Paraná and t ...

and

Río de la Plata Basin The Río de la Plata basin ( es, Cuenca del Plata, pt, Bacia do Prata), more often called the River Plate basin in scholarly writings, sometimes called the Platine basin or Platine region, is the hydrographical area in South America that drains ...

s, as well as rivers in the

Guianas The Guianas, sometimes called by the Spanish loan-word ''Guayanas'' (''Las Guayanas''), is a region in north-eastern South America which includes the following three territories: * French Guiana, an overseas department and region of France * ...

. Here they form part of the highly diverse Neotropical fish fauna. Their habitat preferences varies significantly depending on the exact species. Several species are migratory.Araujo-Lima, C.A.R.M.; and M.L. Ruffino (2004). Migratory Fishes of the Brazilian Amazon. Pp. 233–302 in: Carolsfeld, J.; B. Harvey; C. Ross; and A. Baer (editors). Migratory Fishes of South America.

As exotic species

Pacus have been introduced to the wild in many places outside their native range, both in South America and other continents. They are sometimes released to increase the local fishing, but others are released by

aquarist An aquarist is a person who manages aquariums, either professionally or as a hobby. They typically care for aquatic animals, including fish and marine invertebrates. Some may care for aquatic mammals. Aquarists often work at public aquariums. They ...

s when they outgrow their aquarium. This is illegal in many countries and strongly advised against. When becoming established they can be

invasive species An invasive species otherwise known as an alien is an introduced organism that becomes overpopulated and harms its new environment. Although most introduced species are neutral or beneficial with respect to other species, invasive species ad ...

that damage the local ecosystem. In many regions where individuals have been seen they are unlikely to survive long-term because of temperature. Among the large pacu species (''

'' and ''

''), the most cold-adapted species is ''

'', which tolerates water down to , but stops feeding below .A. A. Agostinho, L. C. Gomes, H. I. Suzuki, H. Ferreira Júlio Jr: ''Migratory fishes of the Upper Paraná River basin, Brazil.'' Núcleo de Pesquisas em Limnologia, Ictiologia e Aquicultura (Nupelia). Universidade Estadual de Maringá. Maringá, Paraná, Brazil.

United States

Pacus have become established in

Puerto Rico Puerto Rico (; abbreviated PR; tnq, Boriken, ''Borinquen''), officially the Commonwealth of Puerto Rico ( es, link=yes, Estado Libre Asociado de Puerto Rico, lit=Free Associated State of Puerto Rico), is a Caribbean island and Unincorporated ...

and singles have been caught in numerous

U.S. state In the United States, a state is a constituent political entity, of which there are 50. Bound together in a political union, each state holds governmental jurisdiction over a separate and defined geographic territory where it shares its sover ...

s.Nico, L.; P. Fuller; and M. Neilson (22 October 2013)
Colossoma macropomum.
USGS Nonindigenous Aquatic Species Database, Gainesville, FL. Retrieved 13 March 2017. Discoveries have been reported in

Alabama (We dare defend our rights) , anthem = "Alabama (state song), Alabama" , image_map = Alabama in United States.svg , seat = Montgomery, Alabama, Montgomery , LargestCity = Huntsville, Alabama, Huntsville , LargestCounty = Baldwin County, Al ...

Arizona Arizona ( ; nv, Hoozdo Hahoodzo ; ood, Alĭ ṣonak ) is a state in the Southwestern United States. It is the 6th largest and the 14th most populous of the 50 states. Its capital and largest city is Phoenix. Arizona is part of the Fou ...

Arkansas Arkansas ( ) is a landlocked state in the South Central United States. It is bordered by Missouri to the north, Tennessee and Mississippi to the east, Louisiana to the south, and Texas and Oklahoma to the west. Its name is from the Osage ...

California California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territori ...

Colorado Colorado (, other variants) is a state in the Mountain West subregion of the Western United States. It encompasses most of the Southern Rocky Mountains, as well as the northeastern portion of the Colorado Plateau and the western edge of t ...

Florida Florida is a state located in the Southeastern region of the United States. Florida is bordered to the west by the Gulf of Mexico, to the northwest by Alabama, to the north by Georgia, to the east by the Bahamas and Atlantic Ocean, and to ...

Georgia Georgia most commonly refers to: * Georgia (country), a country in the Caucasus region of Eurasia * Georgia (U.S. state), a state in the Southeast United States Georgia may also refer to: Places Historical states and entities * Related to the ...

Hawaii Hawaii ( ; haw, Hawaii or ) is a state in the Western United States, located in the Pacific Ocean about from the U.S. mainland. It is the only U.S. state outside North America, the only state that is an archipelago, and the only stat ...

Iowa Iowa () is a state in the Midwestern region of the United States, bordered by the Mississippi River to the east and the Missouri River and Big Sioux River to the west. It is bordered by six states: Wisconsin to the northeast, Illinois to the ...

Idaho Idaho ( ) is a state in the Pacific Northwest region of the Western United States. To the north, it shares a small portion of the Canada–United States border with the province of British Columbia. It borders the states of Montana and Wyom ...

Illinois Illinois ( ) is a U.S. state, state in the Midwestern United States, Midwestern United States. Its largest metropolitan areas include the Chicago metropolitan area, and the Metro East section, of Greater St. Louis. Other smaller metropolita ...

Indiana Indiana () is a U.S. state in the Midwestern United States. It is the 38th-largest by area and the 17th-most populous of the 50 States. Its capital and largest city is Indianapolis. Indiana was admitted to the United States as the 19th s ...

Kansas Kansas () is a state in the Midwestern United States. Its capital is Topeka, and its largest city is Wichita. Kansas is a landlocked state bordered by Nebraska to the north; Missouri to the east; Oklahoma to the south; and Colorado to the ...

Kentucky Kentucky ( , ), officially the Commonwealth of Kentucky, is a state in the Southeastern region of the United States and one of the states of the Upper South. It borders Illinois, Indiana, and Ohio to the north; West Virginia and Virginia to ...

Maine Maine () is a state in the New England and Northeastern regions of the United States. It borders New Hampshire to the west, the Gulf of Maine to the southeast, and the Canadian provinces of New Brunswick and Quebec to the northeast and north ...

Maryland Maryland ( ) is a state in the Mid-Atlantic region of the United States. It shares borders with Virginia, West Virginia, and the District of Columbia to its south and west; Pennsylvania to its north; and Delaware and the Atlantic Ocean to ...

Massachusetts Massachusetts (Massachusett language, Massachusett: ''Muhsachuweesut assachusett writing systems, məhswatʃəwiːsət'' English: , ), officially the Commonwealth of Massachusetts, is the most populous U.S. state, state in the New England ...

Michigan Michigan () is a state in the Great Lakes region of the upper Midwestern United States. With a population of nearly 10.12 million and an area of nearly , Michigan is the 10th-largest state by population, the 11th-largest by area, and the ...

Minnesota Minnesota () is a state in the upper midwestern region of the United States. It is the 12th largest U.S. state in area and the 22nd most populous, with over 5.75 million residents. Minnesota is home to western prairies, now given over to ...

Mississippi Mississippi () is a state in the Southeastern region of the United States, bordered to the north by Tennessee; to the east by Alabama; to the south by the Gulf of Mexico; to the southwest by Louisiana; and to the northwest by Arkansas. Miss ...

Missouri Missouri is a U.S. state, state in the Midwestern United States, Midwestern region of the United States. Ranking List of U.S. states and territories by area, 21st in land area, it is bordered by eight states (tied for the most with Tennessee ...

Nebraska Nebraska () is a state in the Midwestern region of the United States. It is bordered by South Dakota to the north; Iowa to the east and Missouri to the southeast, both across the Missouri River; Kansas to the south; Colorado to the southwe ...

New Hampshire New Hampshire is a U.S. state, state in the New England region of the northeastern United States. It is bordered by Massachusetts to the south, Vermont to the west, Maine and the Gulf of Maine to the east, and the Canadian province of Quebec t ...

New Jersey New Jersey is a state in the Mid-Atlantic and Northeastern regions of the United States. It is bordered on the north and east by the state of New York; on the east, southeast, and south by the Atlantic Ocean; on the west by the Delaware ...

New York New York most commonly refers to: * New York City, the most populous city in the United States, located in the state of New York * New York (state), a state in the northeastern United States New York may also refer to: Film and television * '' ...

North Carolina North Carolina () is a state in the Southeastern region of the United States. The state is the 28th largest and 9th-most populous of the United States. It is bordered by Virginia to the north, the Atlantic Ocean to the east, Georgia and So ...

North Dakota North Dakota () is a U.S. state in the Upper Midwest, named after the Native Americans in the United States, indigenous Dakota people, Dakota Sioux. North Dakota is bordered by the Canadian provinces of Saskatchewan and Manitoba to the north a ...

Ohio Ohio () is a state in the Midwestern region of the United States. Of the fifty U.S. states, it is the 34th-largest by area, and with a population of nearly 11.8 million, is the seventh-most populous and tenth-most densely populated. The sta ...

Oklahoma Oklahoma (; Choctaw language, Choctaw: ; chr, ᎣᎧᎳᎰᎹ, ''Okalahoma'' ) is a U.S. state, state in the South Central United States, South Central region of the United States, bordered by Texas on the south and west, Kansas on the nor ...

Pennsylvania Pennsylvania (; ( Pennsylvania Dutch: )), officially the Commonwealth of Pennsylvania, is a state spanning the Mid-Atlantic, Northeastern, Appalachian, and Great Lakes regions of the United States. It borders Delaware to its southeast, ...

South Carolina )''Animis opibusque parati'' ( for, , Latin, Prepared in mind and resources, links=no) , anthem = " Carolina";" South Carolina On My Mind" , Former = Province of South Carolina , seat = Columbia , LargestCity = Charleston , LargestMetro = ...

Texas Texas (, ; Spanish language, Spanish: ''Texas'', ''Tejas'') is a state in the South Central United States, South Central region of the United States. At 268,596 square miles (695,662 km2), and with more than 29.1 million residents in 2 ...

Utah Utah ( , ) is a state in the Mountain West subregion of the Western United States. Utah is a landlocked U.S. state bordered to its east by Colorado, to its northeast by Wyoming, to its north by Idaho, to its south by Arizona, and to it ...

Washington Washington commonly refers to: * Washington (state), United States * Washington, D.C., the capital of the United States ** A metonym for the federal government of the United States ** Washington metropolitan area, the metropolitan area centered o ...

Wisconsin Wisconsin () is a state in the upper Midwestern United States. Wisconsin is the 25th-largest state by total area and the 20th-most populous. It is bordered by Minnesota to the west, Iowa to the southwest, Illinois to the south, Lake M ...

, and

Wyoming Wyoming () is a U.S. state, state in the Mountain states, Mountain West subregion of the Western United States. It is bordered by Montana to the north and northwest, South Dakota and Nebraska to the east, Idaho to the west, Utah to the south ...

. Among the numerous recent records are a pacu caught in the California Delta, near Stockton in 2015, two in

Lake St. Clair Lake St. Clair (french: Lac Sainte-Claire) is a freshwater lake that lies between the Canadian province of Ontario and the U.S. state of Michigan. It was named in 1679 by French Catholic explorers after Saint Clare of Assisi, on whose feast day ...

in 2016 and a single in

Lake Huron Lake Huron ( ) is one of the five Great Lakes of North America. Hydrology, Hydrologically, it comprises the easterly portion of Lake Michigan–Huron, having the same surface elevation as Lake Michigan, to which it is connected by the , Strait ...

in 2016. Some state wildlife authorities have advised home aquarists who wish to get rid of overgrown pacu to cut the heads off the fish and dispose of them as

garbage Garbage, trash, rubbish, or refuse is waste material that is discarded by humans, usually due to a perceived lack of utility. The term generally does not encompass bodily waste products, purely liquid or gaseous wastes, or toxic waste produc ...

. Habitattitude, a U.S. national initiative led by the Aquatic Nuisance Species (ANS) Task Force, recommends humanely disposing the fish through a veterinarian or pet retailer, returning them to retailers, or donating them to a local aquarium society, school, or aquatic business. Additionally, aquarium-raised fish can be eaten (see ''

Food fish Food is any substance consumed by an organism for nutritional support. Food is usually of plant, animal, or fungal origin, and contains essential nutrients, such as carbohydrates, fats, proteins, vitamins, or minerals. The substance is ingest ...

'').

Europe

In August 2013, a pacu was discovered in Scandinavian waters; a fisherman pulled a specimen from the

Øresund Øresund or Öresund (, ; da, Øresund ; sv, Öresund ), commonly known in English as the Sound, is a strait which forms the Danish–Swedish border, separating Zealand (Denmark) from Scania (Sweden). The strait has a length of ; its width v ...

, a semi-

brackish Brackish water, sometimes termed brack water, is water occurring in a natural environment that has more salinity than freshwater, but not as much as seawater. It may result from mixing seawater (salt water) and fresh water together, as in estuari ...

strait between

Sweden Sweden, formally the Kingdom of Sweden,The United Nations Group of Experts on Geographical Names states that the country's formal name is the Kingdom of SwedenUNGEGN World Geographical Names, Sweden./ref> is a Nordic country located on ...

and

Denmark ) , song = ( en, "King Christian stood by the lofty mast") , song_type = National and royal anthem , image_map = EU-Denmark.svg , map_caption = , subdivision_type = Sovereign state , subdivision_name = Danish Realm, Kingdom of Denmark ...

. An angler fishing on the river

Seine ) , mouth_location = Le Havre/Honfleur , mouth_coordinates = , mouth_elevation = , progression = , river_system = Seine basin , basin_size = , tributaries_left = Yonne, Loing, Eure, Risle , tributarie ...

Paris Paris () is the capital and most populous city of France, with an estimated population of 2,165,423 residents in 2019 in an area of more than 105 km² (41 sq mi), making it the 30th most densely populated city in the world in 2020. S ...

, France, caught a pacu in August 2013. In June 2016, a pacu was caught in a city pond in

Tula Tula may refer to: Geography Antarctica *Tula Mountains *Tula Point India *Tulā, a solar month in the traditional Indian calendar Iran * Tula, Iran, a village in Hormozgan Province Italy * Tula, Sardinia, municipality (''comune'') in the pr ...

, Russia. In June 2017, a pacu was accidentally caught during a fishing contest at the Port of Drobeta Turnu Severin,

Romania Romania ( ; ro, România ) is a country located at the crossroads of Central Europe, Central, Eastern Europe, Eastern, and Southeast Europe, Southeastern Europe. It borders Bulgaria to the south, Ukraine to the north, Hungary to the west, S ...

. The fish bit one of the fishermen, leading to a general warning being issued in the region, until the origin of the fish can be determined. In August 2017, a pacu was caught in the stream Motala Ström in

Norrköping Norrköping (; ) is a city in the province of Östergötland in eastern Sweden and the seat of Norrköping Municipality, Östergötland County, about 160 km southwest of the national capital Stockholm, 40 km east of county seat Linköp ...

, Sweden. In July 2019, two pacus were caught near

Baia Mare Baia Mare ( , ; hu, Nagybánya; german: Frauenbach or Groß-Neustadt; la, Rivulus Dominarum) is a municipality along the Săsar River, in northwestern Romania; it is the capital of Maramureș County. The city lies in the region of Maramureș ...

, Romania. In September 2020, a pacu weighing approx. was caught in

Zegrze Reservoir The Zegrze Reservoir (or Zegrze Lake, in Polish officially ''Jezioro Zegrzyńskie'', unofficially ''Zalew Zegrzyński'') is a man-made reservoir in Poland, located just north of Warsaw, on the lower course of the Narew river. It is formed by a da ...

in Poland.

Asia

Pacus have become established in tropical Asia, including

Thailand Thailand ( ), historically known as Siam () and officially the Kingdom of Thailand, is a country in Southeast Asia, located at the centre of the Indochinese Peninsula, spanning , with a population of almost 70 million. The country is bo ...

and India.Reenamole, G.R.; and G. D’cruz (2015). New Record of exotic fish red bellied pacu, Piaractus brachypomus (Cuvier, 1818) from Vellayani Fresh Waterlake, Southwest coast of India. International Journal of Science and Research 4(12): 1106—1110.

New Guinea

Pacu were introduced in 1994 to the

Sepik River The Sepik () is the longest river on the island of New Guinea, and the second largest in Oceania by discharge volume after the Fly River. The majority of the river flows through the Papua New Guinea (PNG) provinces of Sandaun (formerly West Sepi ...

, and in 1997 to the

Ramu river The Ramu River is a major river in northern Papua New Guinea. The headwaters of the river are formed in the Kratke Range from where it then travels about northwest to the Bismarck Sea. Along the Ramu's course, it receives numerous tributaries ...

as a food source, due to overfishing of native species. Local people blame the fish for outcompeting native species, including juvenile crocodiles, as well as for several attacks on humans. As a primarily vegetarian fish, red-bellied pacu, have also consumed the floating mats of vegetation in the Sepik River, which operated as fish nurseries and crocodile and bird nesting sites. Thus the entire ecosystem has become impoverished and local people cannot subsist as easily as they once did.

Importance to humans

In their native range, pacus are widely fished and

farmed Agriculture or farming is the practice of cultivating plants and livestock. Agriculture was the key development in the rise of sedentary human civilization, whereby farming of domesticated species created food surpluses that enabled people t ...

. Based on a study by

IBAMA Brazilian Institute of the Environment and Renewable Natural Resources ( pt, Instituto Brasileiro do Meio Ambiente e dos Recursos Naturais Renováveis, IBAMA) is the Brazilian Ministry of the Environment's administrative arm. IBAMA supports anti-d ...

, ''Colossoma macropomum'', ''Piaractus brachypomus'' and ''Mylossoma'' spp. are all in the top-15 of the most caught fish (by weight) in the

Aquaria

Pacu are commonly sold as "vegetarian piranhas" to home

aquarium An aquarium (plural: ''aquariums'' or ''aquaria'') is a vivarium of any size having at least one transparent side in which aquatic plants or animals are kept and displayed. Fishkeepers use aquaria to keep fish, invertebrates, amphibians, aq ...

owners. With the proper equipment and commitment, pacu have been known to make responsive pets. One such example was Swish, a 75-cm (30-inch) pacu owned for over 20 years by a Chinese restaurant (Kau Kau) in the Chinatown district in Seattle, Washington; one aquarium technician said of Swish, "He'd rub his body on your arms, kind of like a dog." However, there is some question of whether the fish are a good choice for the typical

. While they are not aggressive

carnivore A carnivore , or meat-eater (Latin, ''caro'', genitive ''carnis'', meaning meat or "flesh" and ''vorare'' meaning "to devour"), is an animal or plant whose food and energy requirements derive from animal tissues (mainly muscle, fat and other sof ...

s like the piranha, their crushing jaw system, used primarily for eating seeds and nuts, can be hazardous. One

toddler A toddler is a child approximately 12 to 36 months old, though definitions vary. The toddler years are a time of great cognitive, emotional and social development. The word is derived from "to toddle", which means to walk unsteadily, like a child ...

needed surgery after a pacu (misreported as a piranha) bit her finger at Edinburgh Butterfly and Insect World in

Scotland Scotland (, ) is a country that is part of the United Kingdom. Covering the northern third of the island of Great Britain, mainland Scotland has a border with England to the southeast and is otherwise surrounded by the Atlantic Ocean to the ...

. Commenting on the incident, Deep Sea World zoological manager Matthew Kane warned, "Pacus will eat anything, even children's wiggling fingers." If a large population of pacu enters an ecosystem to which it is not native, the fish can have a very adverse effect. Pet stores sell pacu as small as long and neglect to warn customers that fish growth is not inhibited by tank size, contrary to popular fish lore. "Most UK dealers now refuse to stock this species due to the large size and expensive aquarium requirements it demands," according to Practical Fishkeeping magazine's Matt Clarke. Incapable of maintaining large aquaria, overwhelmed hobbyists are suspected of illegally releasing their pacu into wild waterways. As tropical fish, pacu will die in cold weather; as newcomers to an ecosystem, pacu may out-compete native species for available food, habitat, and other resources, or displace them by introducing exotic parasites or diseases. Most wildlife resource authorities prohibit releasing exotic fish, including pacu, into the wild. Officials of one Texas lake have put a $100

bounty Bounty or bounties commonly refers to: * Bounty (reward), an amount of money or other reward offered by an organization for a specific task done with a person or thing Bounty or bounties may also refer to: Geography * Bounty, Saskatchewan, a g ...

on the pacu caught there.

Game fish

In Appendix B of ''Through the Brazilian Wilderness'' (see also online version),

Theodore Roosevelt Theodore Roosevelt Jr. ( ; October 27, 1858 – January 6, 1919), often referred to as Teddy or by his initials, T. R., was an American politician, statesman, soldier, conservationist, naturalist, historian, and writer who served as the 26t ...

advised, "For small fish like the pacu and piranha an ordinary bass hook will do." Concerning the pacu, he added:

"A light rod and reel would be a convenience in catching the pacu. We used to fish for the latter variety in the quiet pools while allowing the canoe to drift, and always saved some of the fish as bait for the big fellows. We fished for the pacu as the native does, kneading a ball of mandioc farina with water and placing it on the hook as bait. I should not be surprised, though, if it were possible, with carefully chosen flies, to catch some of the fish that every once in a while we saw rise to the surface and drag some luckless insect under."

More recently, South American rivers including the Amazon have become a popular destination for recreational anglers, who go to fly fish for pacu. The

International Game Fish Association The International Game Fish Association (''IGFA'') is the leading authority on angling pursuits and the keeper of the most current World Record fishing catches by fish categories. Fishermen who are sport fishers are careful to follow their string ...

has sponsored fly-fishing courses for native Brazilian fishermen, typically accustomed to subsistence fishing, so they can work as guides to fishing

tourist Tourism is travel for pleasure or business; also the theory and practice of touring, the business of attracting, accommodating, and entertaining tourists, and the business of operating tours. The World Tourism Organization defines tourism mo ...

s. When bait-fishing in pacu-stocked ponds, anglers in

Malaysia Malaysia ( ; ) is a country in Southeast Asia. The federation, federal constitutional monarchy consists of States and federal territories of Malaysia, thirteen states and three federal territories, separated by the South China Sea into two r ...

are advised to use circle hooks, size 2 or larger, and braided leather rather than nylon leaders which are easily broken by the pacu's teeth. Since pond pacu often nibble at the bait before taking it, anglers should let them swim away with the bait. If the angler simply allows the line to tighten, the circle hook will slide to the side of the fish's mouth and embed its point there. PreparedPacu VillaTunari

Food fish

Theodore Roosevelt wrote of catching and eating pacu in his book ''Through the Brazilian Wilderness''. He described them as "good-sized, deep-bodied fish," and noted, "They were delicious eating." Today, the Amazon river is experiencing a crisis of overfishing. Both subsistence fishers and their commercial rivals compete in netting large quantities of pacu, which bring good prices at markets in Brazil and abroad.

Aquaculture Aquaculture (less commonly spelled aquiculture), also known as aquafarming, is the controlled cultivation ("farming") of aquatic organisms such as fish, crustaceans, mollusks, algae and other organisms of value such as aquatic plants (e.g. lot ...

may relieve the overfishing crisis, as well as improve food security by boosting fish supplies. Various species of pacu are increasingly being used for warm-water farm fishing around the world. Pacu are considered ideal for their tolerance of the low-oxygen water in farm ponds. They also don't require a lot of expensive protein in their diet, and can be raised year-round in warm or temperature-controlled environments. Research shows that the "flavor of

armed Armed (May, 1941–1964) was an American Thoroughbred gelding race horse who was the American Horse of the Year in 1947 and Champion Older Male Horse in both 1946 and 1947. He was inducted into the National Museum of Racing and Hall of Fame in ...

pacu is comparable to that of hybrid

striped bass The striped bass (''Morone saxatilis''), also called the Atlantic striped bass, striper, linesider, rock, or rockfish, is an anadromous perciform fish of the family Moronidae found primarily along the Atlantic coast of North America. It has al ...

tilapia Tilapia ( ) is the common name for nearly a hundred species of cichlid fish from the coelotilapine, coptodonine, heterotilapine, oreochromine, pelmatolapiine, and tilapiine tribes (formerly all were "Tilapiini"), with the economically most ...

, and

rainbow trout The rainbow trout (''Oncorhynchus mykiss'') is a species of trout native to cold-water tributaries of the Pacific Ocean in Asia and North America. The steelhead (sometimes called "steelhead trout") is an anadromous (sea-run) form of the coasta ...

, but superior to catfish." In South America, pacu are prized for their sweet, mild flavor. Aquarium-raised pacu can be cooked and eaten, but care should be taken to ensure that no toxic medications were used in the aquarium. A recipe and preparation instructions are provided on the Greater Seattle Aquarium Society's Web site.

Incorrect claim of testicle-biting

In 2013, a pacu was caught in the Øresund, a strait between Sweden and Denmark. This led to media reports mistakenly warning that the fish could attack

testicles A testicle or testis (plural testes) is the male reproductive gland or gonad in all bilaterians, including humans. It is homologous to the female ovary. The functions of the testes are to produce both sperm and androgens, primarily testostero ...

. The reports were based on a joke (referring to their actual feeding on tree nuts) that was not meant to be taken seriously. Nevertheless, their very strong jaws made for crushing plant seeds and the like means that fishermen and aquarists sometimes are warned about the powerful bite that may cause traumatic injuries.

References

{{reflist, colwidth=30em, refs= {{cite news , last = Lucariello , first = Kathryn , title =Toothy fish caught on White River is piranha cousin , url=http://www.eurekaspringstimesecho.com/articles/2006/07/13/news/mw1.txt , publisher= Carroll County News,

Eureka Springs Eureka Springs is a city in Carroll County, Arkansas, United States, and one of two county seats for the county. It is located in the Ozark Mountains of northwest Arkansas, near the border with Missouri. As of the 2020 census, the city populati ...

, date=2006-07-13 {{cite web , last = Magallanes , first = Frank , title = Subfamily Serrasalminae , url = http://www.opefe.com/serrasalminae.html , publisher = Oregon Piranha Exotic Fish Exhibit , date = 2006-04-06 , format = Website {{cite news , title = Chinatown fixture Swish was "part of the family" , url = http://seattletimes.nwsource.com/html/localnews/2003304026_fish14m.html , date = 2006-10-14 , first = Florangela , last = Davila , newspaper = The Seattle Times , url-status = dead , archive-url = https://web.archive.org/web/20061105034253/http://seattletimes.nwsource.com/html/localnews/2003304026_fish14m.html , archive-date = 5 November 2006 {{cite news , first=Gareth , last=Edwards , title=Girl needs surgery for piranha bite to finger , date= 2004-06-12 , newspaper=The Scotsman , url=http://www.scotsman.com/news/girl-needs-surgery-for-piranha-bite-to-finger-1-1019458 {{cite web , last = Magallanes , first = Frank , title = Pacu, Tambaqui, Piratinga, Silver Dollars , url = http://www.opefe.com/pacu.html , publisher = Oregon Piranha Exotic Fish Exhibit , date = 2006-04-06 , format = Website {{cite news , title = Angler catches fruit-eating piranha , publisher = Practical Fishkeeping,

Peterborough Peterborough () is a cathedral city in Cambridgeshire, east of England. It is the largest part of the City of Peterborough unitary authority district (which covers a larger area than Peterborough itself). It was part of Northamptonshire until ...

UK , date = 2005-08-10 , url = http://www.practicalfishkeeping.co.uk/pfk/pages/item.php?news=698 , first = Matt , last = Clarke , url-status = dead , archive-url = https://web.archive.org/web/20090902232414/http://www.practicalfishkeeping.co.uk/pfk/pages/item.php?news=698 , archive-date = 2 September 2009 {{cite news, title=Mystery Fish Caught At Buffalo Springs Lake Identified , publisher=KLBK news (CBS Affiliate),

Lubbock, Texas Lubbock ( ) is the 10th-most populous city in the U.S. state of Texas and the seat of government of Lubbock County. With a population of 260,993 in 2021, the city is also the 85th-most populous in the United States. The city is in the northw ...

, date=2006-07-19 , url=http://www.klbk13.tv/news/default.asp?mode=shownews&id=1691 {{dead link, date=June 2016, bot=medic{{cbignore, bot=medic {{cite news , last=Hindmond , first=Jade , title=Fish Thought To Be Record Bream Is A Pacu , url=http://www.wtvm.com/Global/story.asp?S=5589820 , date=2006-10-26 , publisher=WTVM News, Columbus, Georgia , access-date=27 October 2006 , archive-url=https://web.archive.org/web/20070927023645/http://www.wtvm.com/Global/story.asp?S=5589820 , archive-date=27 September 2007 , url-status=dead Serrasalmidae Fish common names