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 considerably smaller portion in the Northern Hemisphere. It can also be described as the southern Subregion#Americas, subregion o ...

n freshwater

serrasalmid The Serrasalmidae (serrasalmids) are a family of characiform fishes native to freshwater habitats of South America. They include more than 90 species. The name means "serrated salmon family", which refers to the serrated keel running along the ...

fish related to

piranha A piranha (, or ; ) is any of a number of freshwater fish species in the subfamily Serrasalminae, of the family Serrasalmidae, in the order Characiformes. These fish inhabit South American rivers, floodplains, lakes and reservoirs. Although ...

s. 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 (1855–1 ...

, 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 ...

. 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 (; : genera ) is a taxonomic rank above species and below family as used in the biological classification of living and fossil organisms as well as viruses. In binomial nomenclature, the genus name forms the first part of the binomial s ...

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

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, black- ...

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

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. They ...

'' **''

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 *Subfamily Myleinae **''

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 ...

'' **''

Myleus ''Myleus'' is a genus of serrasalmids from South America, where found in the Amazon, Orinoco and São Francisco basins, as well as the river basin of the Guiana Shield.Ota, R.P., Röpke, C.P., Zuanon, J. & Jégu, M. (2013): Serrasalmidae. ''In'' ...

'' **''

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 m ...

'' **''

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. This vulner ...

'' – parrot pacu, eaglebeak pacu **''

Paramyloplus ''Paramyloplus'' is a genus of freshwater fish in the family Serrasalmidae The Serrasalmidae (serrasalmids) are a family of characiform fishes native to freshwater habitats of South America. They include more than 90 species. The name means " ...

'' **''

Prosomyleus ''Prosomyleus rhomboidalis'' is a medium to large omnivorous fish of the family Serrasalmidae from South America, where it is found in the Amazon River basin, as well as the north and the eastern Guiana Shield The Guiana Shield (; ; ; ) is ...

'' **''

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 Basin, 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 Podostemace ...

'' *Subfamily

Serrasalminae The Serrasalmidae (serrasalmids) are a family of characiform fishes native to freshwater habitats of South America. They include more than 90 species. The name means "serrated salmon family", which refers to the serrated keel running along the b ...

**''

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 floodp ...

'' 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'' also known as the red-bellied Pacu or pirapitinga, is a large species of pacu, a close relative of piranhas and silver dollar (fish), silver dollars, in the serrasalmid family.Nico, L.; P. Fuller; and M. Neilson (22 Octo ...

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

fish farm Fish farming or pisciculture involves commercial breeding of fish, most often for food, in fish tanks or artificial enclosures such as fish ponds. It is a particular type of aquaculture, which is the controlled cultivation and harvesting of aq ...

ers is ''

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

'', also known as Paraná River pacu or small-scaled pacu. Pacu is a term of Tupi-Guaraní 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: * Brazil, a country * Brazilians, its people * Brazilian Portuguese, its dialect Brazilian may also refer to: * "The Brazilian", a 1986 instrumental music piece by Genesis * Brazilian Café, Baghdad, Iraq (1937) * Bra ...

, 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 Paraná, Paranã or Parana may refer to: Geology * Paraná Basin, a sedimentary basin in South America Places In Argentina *Paraná, Entre Ríos, a city * Paraná Department, a part of Entre Ríos Province In Brazil *Paraná (state), a state ...

Paraguay Paraguay, officially the Republic of Paraguay, is a landlocked country in South America. It is bordered by Argentina to the Argentina–Paraguay border, south and southwest, Brazil to the Brazil–Paraguay border, east and northeast, and Boli ...

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 Tetra is the common name of many small freshwater characiform fishes. Tetras come from Africa, Central America, and South America, belonging to the biological families Characidae, Alestidae (the "African tetras"), Lepidarchidae, Lebiasi ...

, 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.: "Relationsh ...

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, 35,800 species of fish had been described as of March 2 ...

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 native to freshwater habitats of South America. They include more than 90 species. The name means "serrated salmon family", which refers to the serrated keel running along the ...

(formerly a subfamily of

Characidae Characidae, the characids, is a family of freshwater subtropical and tropical fish belonging to the order Characiformes. They are found throughout much of Central and South America, including such major waterways as the Amazon and Orinoco Riv ...

). 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 immediately to the Northern Hemisphere, north and Southern Hemisphere, south of the tropics. Geographically part of the Ge ...

South America. They inhabit rivers, lakes,

floodplain A floodplain or flood plain or bottomlands is an area of land adjacent to a river. Floodplains stretch from the banks of a river channel to the base of the enclosing valley, and experience flooding during periods of high Discharge (hydrolog ...

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 foun ...

s in the

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

Orinoco The Orinoco () is one of the longest rivers in South America at . Its drainage basin, sometimes known as the Orinoquia, covers approximately 1 million km2, with 65% of it in Venezuela and 35% in Colombia. It is the List of rivers by discharge, f ...

São Francisco River The São Francisco River (, ) is a large Rivers of Brazil, 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 R ...

and

Río de la Plata Basin The Río de la Plata basin (, ), more often called the River Plate basin in scholarly writings, sometimes called the Platine basin or Platine region, is the Hydrography, hydrographical area in South America that drains to the Río de la Plata. I ...

s, as well as rivers in the

Guianas The Guianas, also spelled Guyanas or Guayanas, are a geographical region in north-eastern South America. Strictly, the term refers to the three Guianas: Guyana, Suriname, and French Guiana, formerly British Guiana, British, Surinam (Dutch colo ...

. 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 is an introduced species that harms its new environment. Invasive species adversely affect habitats and bioregions, causing ecological, environmental, and/or economic damage. The term can also be used for native spec ...

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 ; abbreviated PR), officially the Commonwealth of Puerto Rico, is a Government of Puerto Rico, self-governing Caribbean Geography of Puerto Rico, archipelago and island organized as an Territories of the United States, unincorporated territo ...

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 so ...

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 Alabama ( ) is a U.S. state, state in the Southeastern United States, Southeastern and Deep South, Deep Southern regions of the United States. It borders Tennessee to the north, Georgia (U.S. state), Georgia to the east, Florida and the Gu ...

Arizona Arizona is a U.S. state, state in the Southwestern United States, Southwestern region of the United States, sharing the Four Corners region of the western United States with Colorado, New Mexico, and Utah. It also borders Nevada to the nort ...

Arkansas Arkansas ( ) is a landlocked state in the West South Central region of the Southern United States. It borders Missouri to the north, Tennessee and Mississippi to the east, Louisiana to the south, Texas to the southwest, and Oklahoma ...

California California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...

Colorado Colorado is a U.S. state, state in the Western United States. It is one of the Mountain states, sharing the Four Corners region with Arizona, New Mexico, and Utah. It is also bordered by Wyoming to the north, Nebraska to the northeast, Kansas ...

Florida Florida ( ; ) is a U.S. state, state in the Southeastern United States, Southeastern region of the United States. It borders the Gulf of Mexico to the west, Alabama to the northwest, Georgia (U.S. state), Georgia to the north, the Atlantic ...

Georgia Georgia most commonly refers to: * Georgia (country), a country in the South Caucasus * Georgia (U.S. state), a state in the southeastern United States Georgia may also refer to: People and fictional characters * Georgia (name), a list of pe ...

Hawaii Hawaii ( ; ) is an island U.S. state, state of the United States, in the Pacific Ocean about southwest of the U.S. mainland. One of the two Non-contiguous United States, non-contiguous U.S. states (along with Alaska), it is the only sta ...

Iowa Iowa ( ) is a U.S. state, state in the upper Midwestern United States, Midwestern region of the United States. It borders the Mississippi River to the east and the Missouri River and Big Sioux River to the west; Wisconsin to the northeast, Ill ...

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Kansas Kansas ( ) is a landlocked U.S. state, state in the Midwestern United States, Midwestern region of the United States. It borders Nebraska to the north; Missouri to the east; Oklahoma to the south; and Colorado to the west. Kansas is named a ...

Kentucky Kentucky (, ), officially the Commonwealth of Kentucky, is a landlocked U.S. state, state in the Southeastern United States, Southeastern region of the United States. It borders Illinois, Indiana, and Ohio to the north, West Virginia to the ...

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Mississippi Mississippi ( ) is a U.S. state, state in the Southeastern United States, Southeastern and Deep South regions of the United States. It borders Tennessee to the north, Alabama to the east, the Gulf of Mexico to the south, Louisiana to the s ...

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North Dakota North Dakota ( ) is a U.S. state in the Upper Midwest, named after the indigenous Dakota people, Dakota and Sioux peoples. It is bordered by the Canadian provinces of Saskatchewan and Manitoba to the north and by the U.S. states of Minneso ...

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, and

Wyoming Wyoming ( ) is a landlocked U.S. state, state in the Mountain states, Mountain West subregion of the Western United States, Western United States. It borders Montana to the north and northwest, South Dakota and Nebraska to the east, Idaho t ...

. 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 () 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 they first saw the lake. ...

in 2016 and a single in

Lake Huron Lake Huron ( ) is one of the five Great Lakes of North America. It is shared on the north and east by the Canadian province of Ontario and on the south and west by the U.S. state of Michigan. The name of the lake is derived from early French ex ...

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 (American English), rubbish (British English), 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 ...

. 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 Many species of fish are caught by humans and consumed as food in virtually all regions around the world. Their meat has been an important dietary source of protein and other nutrients in the human diet. The English language does not have a s ...

'').

Europe

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

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

, 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, is a Nordic countries, Nordic country located on the Scandinavian Peninsula in Northern Europe. It borders Norway to the west and north, and Finland to the east. At , Sweden is the largest Nordic count ...

and

Denmark Denmark is a Nordic countries, Nordic country in Northern Europe. It is the metropole and most populous constituent of the Kingdom of Denmark,, . also known as the Danish Realm, a constitutionally unitary state that includes the Autonomous a ...

. An angler fishing on the river

Seine The Seine ( , ) is a river in northern France. Its drainage basin is in the Paris Basin (a geological relative lowland) covering most of northern France. It rises at Source-Seine, northwest of Dijon in northeastern France in the Langres plat ...

Paris Paris () is the Capital city, capital and List of communes in France with over 20,000 inhabitants, largest city of France. With an estimated population of 2,048,472 residents in January 2025 in an area of more than , Paris is the List of ci ...

, France, caught a pacu in August 2013. In June 2016, a pacu was caught in a city pond in Tula, Russia. In June 2017, a pacu was accidentally caught during a fishing contest at the

Port of Drobeta Turnu Severin The Port of Drobeta-Turnu Severin is one of the largest Romanian river ports, located in the city of Drobeta-Turnu Severin on the Danube River The Danube ( ; see also other names) is the second-longest river in Europe, after the Volga in ...

Romania Romania is a country located at the crossroads of Central Europe, Central, Eastern Europe, Eastern and Southeast Europe. It borders Ukraine to the north and east, Hungary to the west, Serbia to the southwest, Bulgaria to the south, Moldova to ...

. 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 Lin ...

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

Baia Mare Baia Mare ( , ; ; ; ) is a Municipiu, city along the Săsar, Săsar River, in northwestern Romania; it is the capital of Maramureș County. The city lies in the region of Maramureș, a subregion of Transylvania. It is situated about from Buchare ...

, Romania. In September 2020, a pacu weighing approx. was caught in Zegrze Reservoir in Poland. In February 2024, a dead pacu was found in

Garadice Lough Garadice Lough (), also known as Garadice Lake or Lough Garadice, is a freshwater lake in County Leitrim, Ireland. It is located in the south of the county and now forms part of the Shannon–Erne Waterway. Geography Garadice Lough is located ...

, Ireland.Ryan, E. (2024, February 20). Angler’s shock after discovering South American fish in County Leitrim lake. Independent.ie. Retrieved March 6, 2024, from https://www.independent.ie/regionals/leitrim/news/anglers-shock-after-discovering-south-american-fish-in-county-leitrim-lake/a341554745.htmlRTÉ News. (2024, February 23). Pacu fish, native to the Amazon, found in Lough Garadice. RTE.ie. Retrieved March 6, 2024, from https://www.rte.ie/news/regional/2024/0223/1434059-pacu-fish/

Asia

Pacus have become established in tropical Asia, including Vietnam, Malaysia, Bangladesh,

Thailand Thailand, officially the Kingdom of Thailand and historically known as Siam (the official name until 1939), is a country in Southeast Asia on the Mainland Southeast Asia, Indochinese Peninsula. With a population of almost 66 million, it spa ...

, 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 third largest in Oceania by discharge volume after the Fly River, Fly and Mamberamo River, Mamberamo. The majority of the river flows through the Papua New Guinea (PNG) provi ...

, 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. Based on a study by

IBAMA The Brazilian Institute of the Environment and Renewable Natural Resources ( Portuguese: ''Instituto Brasileiro do Meio Ambiente e dos Recursos Naturais Renováveis'', IBAMA) is a government agency under the administration of the Brazilian Minis ...

, ''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 (: 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. fishkeeping, Fishkeepers use aquaria to keep fish, invertebrates, amphibians, aquati ...

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 Plants are the eukaryotes that form the Kingdom (biology), kingdom Plantae; they ar ...

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 1 to 3 years old, though definitions vary. The toddler years are a time of great cognitive, emotional and social development. The word is derived from "toddle", which means to walk unsteadily, as children at thi ...

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

Scotland Scotland is a Countries of the United Kingdom, country that is part of the United Kingdom. It contains nearly one-third of the United Kingdom's land area, consisting of the northern part of the island of Great Britain and more than 790 adjac ...

. 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 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), also known as Teddy or T.R., was the 26th president of the United States, serving from 1901 to 1909. Roosevelt previously was involved in New York (state), New York politics, incl ...

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 and anglers are careful to follow ...

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, and the commercial activity of providing and supporting such travel. UN Tourism defines tourism more generally, in terms which go "beyond the common perception of tourism as being limited to holiday activity on ...

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

Malaysia Malaysia is a country in Southeast Asia. Featuring the Tanjung Piai, southernmost point of continental Eurasia, it is a federation, federal constitutional monarchy consisting of States and federal territories of Malaysia, 13 states and thre ...

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. Nelu ...

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 ...

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 mos ...

, and

rainbow trout The rainbow trout (''Oncorhynchus mykiss'') is a species of trout native to cold-water tributary, tributaries of the Pacific Ocean in North America and Asia. The steelhead (sometimes called steelhead trout) is an Fish migration#Classification, ...

, 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 ( testes) is the gonad in all male bilaterians, including humans, and is homologous to the ovary in females. Its primary functions are the production of sperm and the secretion of androgens, primarily testosterone. The ...

. The reports were based on a joke (referring to their actual feeding on

tree nut A nut is a fruit consisting of a hard or tough nutshell protecting a kernel which is usually edible. In general usage and in a culinary sense, many dry seeds are called nuts, but in a botanical context, "nut" implies that the shell does not open ...

s) 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,

, 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 City status in the United Kingdom, cathedral city in the City of Peterborough district in the Ceremonial counties of England, ceremonial county of Cambridgeshire, England. The city is north of London, on the River Nene. A ...

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 a city in the U.S. state of Texas and the county seat of Lubbock County. With a population of 272,086 in 2024, Lubbock is the 10th-most populous city in Texas and the 84th-most populous in the United States. The city is in the ...

, 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