Feeder fish is the

common name In biology, a common name of a taxon or organism (also known as a vernacular name, English name, colloquial name, country name, popular name, or farmer's name) is a name that is based on the normal language of everyday life; and is often contra ...

for certain types of small, inexpensive

fish Fish are aquatic, craniate, gill-bearing animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups. Approximately 95% ...

commonly fed as live food to other captive animals such as

predatory fish Predatory fish are hypercarnivorous fish that actively prey upon other fish or aquatic animals, with examples including shark, billfish, barracuda, pike/muskellunge, walleye, perch and salmon. Some omnivorous fish, such as the red-bellied pir ...

es (e.g. aquarium sharks, farmed salmon and

tuna A tuna is a saltwater fish that belongs to the tribe Thunnini, a subgrouping of the Scombridae ( mackerel) family. The Thunnini comprise 15 species across five genera, the sizes of which vary greatly, ranging from the bullet tuna (max le ...

) or carnivorous

aquarium fish Lists of aquarium life include lists of fish, amphibians, invertebrates and plants in freshwater, brackish and marine aquariums. In fishkeeping, suitable species of aquarium fish, plants and other organisms vary with the size, water chemistry and ...

(e.g. oscars, gar,

grouper Groupers are fish of any of a number of genera in the subfamily Epinephelinae of the family Serranidae, in the order Perciformes. Not all serranids are called "groupers"; the family also includes the sea basses. The common name "grouper" is ...

and rays),

turtle Turtles are an order of reptiles known as Testudines, characterized by a special shell developed mainly from their ribs. Modern turtles are divided into two major groups, the Pleurodira (side necked turtles) and Cryptodira (hidden necked ...

crocodilian Crocodilia (or Crocodylia, both ) is an order of mostly large, predatory, semiaquatic reptiles, known as crocodilians. They first appeared 95 million years ago in the Late Cretaceous period ( Cenomanian stage) and are the closest living ...

s and other piscivores that naturally hunt in fresh,

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 ...

salt water Saline water (more commonly known as salt water) is water that contains a high concentration of dissolved salts (mainly sodium chloride). On the United States Geological Survey (USGS) salinity scale, saline water is saltier than brackish water, ...

ecosystems (

zoo animal A zoo (short for zoological garden; also called an animal park or menagerie) is a facility in which animals are kept within enclosures for public exhibition and often bred for Conservation biology, conservation purposes. The term ''zoological g ...

s such as

grizzlies Grizzlies may refer to: *Grizzly bears Sports ; Sports teams named after the grizzly bear: United States: * Memphis Grizzlies, a National Basketball Association team in Memphis, Tennessee * Fresno Grizzlies, a Triple-A minor league baseball team b ...

, water snakes,

cetacean Cetacea (; , ) is an infraorder of aquatic mammals that includes whales, dolphins, and porpoises. Key characteristics are their fully aquatic lifestyle, streamlined body shape, often large size and exclusively carnivorous diet. They propel them ...

pinniped Pinnipeds (pronounced ), commonly known as seals, are a widely range (biology), distributed and diverse clade of carnivorous, fin-footed, semiaquatic, mostly marine mammal, marine mammals. They comprise the extant taxon, extant family (biology ...

s and

penguin Penguins ( order Sphenisciformes , family Spheniscidae ) are a group of aquatic flightless birds. They live almost exclusively in the Southern Hemisphere: only one species, the Galápagos penguin, is found north of the Equator. Highly adapt ...

s).

Advantages of using feeder fish

The species of fish usually sold as feeder fish are invariably some of the easiest fish for

fishkeepers Fishkeeping is a popular hobby, practiced by aquarists, concerned with keeping fish in a home aquarium or garden pond. There is also a piscicultural fishkeeping industry, serving as a branch of agriculture. Origins of fishkeeping Fish have ...

to rear and breed, such as common goldfish, guppies and

fathead minnow Fathead minnow (''Pimephales promelas''), also known as fathead or tuffy, is a species of temperate freshwater fish belonging to the genus '' Pimephales'' of the cyprinid family. The natural geographic range extends throughout much of North Ame ...

. Typically, these species are tolerant of overcrowding and have a high

fecundity Fecundity is defined in two ways; in human demography, it is the potential for reproduction of a recorded population as opposed to a sole organism, while in population biology, it is considered similar to fertility, the natural capability to pr ...

and rapid growth rate. This makes it easy for fish farmers, retailers, and hobbyists to maintain large populations of these fish that can be sold at a much more affordable price than the more ornamental fish that require better conditions. In some cases, species of predatory animals, typically large fish such as

catfish Catfish (or catfishes; order Siluriformes or Nematognathi) are a diverse group of ray-finned fish. Named for their prominent barbels, which resemble a cat's whiskers, catfish range in size and behavior from the three largest species alive, ...

and

cichlid Cichlids are fish from the family Cichlidae in the order Cichliformes. Cichlids were traditionally classed in a suborder, the Labroidei, along with the wrasses ( Labridae), in the order Perciformes, but molecular studies have contradicted th ...

s, but sometimes also animals such as freshwater

s, are provided with feeder fish, because they accept them more readily than alternatives. Other animal keepers believe that feeder fish are particularly nutritious, being what one would expect their pets would eat in the wild; some others view feeder fish as a stimulating treat that encourages predatory animals to exercise their natural hunting behaviours. Some animal keepers enjoy watching the hunting and eating techniques involved when

predation Predation is a biological interaction In ecology, a biological interaction is the effect that a pair of organisms living together in a community have on each other. They can be either of the same species (intraspecific interactions), or o ...

occurs.

Disadvantages of using feeder fish

Some aquarists view the use of feeder fish as cruel and unnecessary, often arguing that once the feeder fish is introduced into a small tank, it has no chance to escape, and such a situation cannot be considered "natural". Most predatory species that eat live fish can also be weaned onto dead alternatives. Some of the species used as feeder fish (

goldfish The goldfish (''Carassius auratus'') is a freshwater fish in the family Cyprinidae of order Cypriniformes. It is commonly kept as a pet in indoor aquariums, and is one of the most popular aquarium fish. Goldfish released into the wild have b ...

and rosy red minnows) contain high quantities of thiaminase, an enzyme that destroys

thiamine Thiamine, also known as thiamin and vitamin B1, is a vitamin, an essential micronutrient, that cannot be made in the body. It is found in food and commercially synthesized to be a dietary supplement or medication. Phosphorylated forms of t ...

(vitamin B₁) and when fed in large quantities can cause nutritional imbalances. When bred and held in an overcrowded or otherwise sub-optimal environment, they may also carry bacterial infections and parasites, which can be passed along to fish that consume them. A disadvantage of using feeder fish, particularly goldfish, is that they do not accurately simulate what a tropical fish might eat in the wild.

Species use

Several fast-growing and hardy species are commonly sold and used as feeder fish. Depending on the locality, feeder fish may include:　 * Low-quality, common livebearers, usually guppies, mosquito fish and platies * Small cyprinids, particularly rosy red minnows and

* Undesirable livebearer and

fry * Female

Siamese fighting fish The Siamese fighting fish (''Betta splendens''), commonly known as the betta, is a freshwater fish native to Southeast Asia, namely Cambodia, Laos, Myanmar, Malaysia, Indonesia, Thailand, and Vietnam. It is one of 73 species of the genus '' B ...

* Young

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 i ...

* Defective fry

Opinions within the hobby

Although the use of feeder fish is fairly common in the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 U.S. state, states, a Washington, D.C., federal district, five ma ...

, in the

United Kingdom The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Europe, off the north-western coast of the European mainland, continental mainland. It comprises England, Scotlan ...

it is much less commonplace, with aquarists and hobby magazines in Britain generally rejecting the use of feeder fish as being unnecessary and likely to cause health problems.

References

External links