SRAC Publication No. 140

Revision VI PR September 2008

Forage – Introduction and Species Nathan Stone1

Forage fish are stocked in recreational ing fathead at the same time Unless they are feed-trained when ponds as food for sport fish as the makes food available young and maintained on a feed diet, such as largemouth . Early trials to bass during the spring before the will not consume found that largemouth bass stocked bluegill start spawning. fish feed directly. However, bass will alone did not grow well, and that an Stocking also may be benefit from the additional production ample supply of small, forage fish appropriate when the pond owner of sunfish and other forage species was necessary to produce high-quality wants to provide additional food for that readily consume commercial fish bass. This publication describes fish in a pond with an exist- feeds. species that are particularly suitable ing fish population. For example, in Determining the need for forage fish, for forage. a bass-bluegill pond managed for big proper forage rates, and There are two situations in which bass, bass production is often limited best management practices is a com- stocking forage fish is appropriate. by the amount of available prey. Fish plex process. Before adding forage Adding forage fish is a routine, rec- such as golden shiners and threadfin fish, obtain farm pond management ommended practice when stocking shad are added to ponds with exist- information from your Cooperative new or renovated ponds (ponds from ing sunfish populations as additional Extension Service and consult with a which the fish population has been forage species. Combinations of farm pond professional to seek addi- eliminated). In the south, bluegill is forage species may also be stocked tional guidance. There are reputable, the best overall forage fish for large- to increase the total forage base. experienced, private consulting firms mouth bass. Adding some redear sun- Fathead minnows and can be that offer complete farm pond evalua- fish in addition to the bluegill is com- stocked as forage in ponds, tion and management services. monly recommended for snail control, but fatheads usually are not recom- for additional forage, and for addition- mended for ponds with existing bass al sport fishing. If ponds are managed populations because they disappear so Characteristics of properly, sunfish alone will provide rapidly. There are trade-offs involved a good forage fish enough forage to produce high-quality with each of these forage species, so What makes for a good forage fish? It bass as long as bass are harvested they must be chosen carefully. is a species that grows well in ponds, periodically. Bluegill and redear sun- Stocking new forage species is not feeds low on the , does fish will grow and reproduce in the always the solution for underfed bass not compete with young bass for pond, creating a long-term food source populations. The problem may be food, has a small size as an adult, and for predatory fish. In ponds without too many bass or competing species reproduces prolifically and frequently. fish, the typical recommendation is such as bullheads or green sunfish. It is essential that forage fish be to stock fingerling bluegill in the fall The pond “balance” between the bass small enough to serve as prey for the so that they will mature, and and bream populations may need to desired sport fish. While many forage provide forage for largemouth bass be adjusted. Or, the pond may need species will have some overlap in diet fingerlings stocked in the spring. Add- to be managed properly by improv- with young bass, the key consider- ing the food supply for fish through ation is to avoid competition for food 1 / Center, University of Arkansas at Pine Bluff liming (if needed) or fertilization. at the same time. Another desirable characteristic of tant to consider that stocked fish may Coloration is variable, and males and a forage fish species is the ability to migrate downstream into other ponds females differ in color, especially in turn unexploited natural foods in and natural waters. the breeding season. Breeding males the pond (, insects and insect become a dark bluish-green with larvae, snails, etc.) into food for desir- Forage fish species darker, vertical bars; the head has able predatory fish. The presence of bright blue tones and the breast devel- forage fish enhances the growth of The following are common forage ops a rusty orange color. Females are bass and can improve their survival in the southern . lighter in color, with faint vertical bars through the winter, which is particu- Not all are recommended or permis- and a white to grayish-white belly. larly important for young-of-the-year sible in all states. Be sure to check Bluegill feed on a wide variety of bass. Periodic additions of forage fish with your state Natural Resources natural foods, including insect larvae, such as fathead minnows or golden Department for a list of species ap- insects, , small fish, fish shiners should increase bass pro- proved for pond stocking, as regula- eggs, snails and . They also duction, but this can be expensive. tions and recommendations change eat some vegetation. Commercial fish Laboratory studies have shown that over time. feeds can be fed to bluegill. Bluegill it takes about 4 to 5 pounds of forage Bluegill are considered to be fine sport fish fish to produce a pound of large- The bluegill sunfish, macro- and table-fare in their own right, and mouth bass. But in ponds, where for- chirus (also called bream or brim), is offer additional opportunities age fish can escape or be lost to other the most common forage fish stocked in farm ponds. predators, 8 to 10 pounds of forage in farm ponds in the south. Adults per pound of bass is more realistic. reach 6 to 10 inches in length. Male They are native to much of the eastern U.S. (Mississippi River basin, Body shape affects the suitability of bluegill will sweep out a nest in the Atlantic and Gulf Slope drainages) a fish species as forage, but is less pond bottom, forming a circular and are now common across the con- critical than other characteristics. depression. Clusters of these nests are tinental U.S. The bluegill is the most important found together in shallow water and and common forage fish species, but are called “beds.” Bluegill start spawn- The coppernose bluegill, L. macrochi- is not necessarily preferred by bass, ing in late spring at around rus purpurescens (also designated as L. probably because of its body shape 70 ºF (21 ºC) and spawn periodically m. mystacalis), is a subspecies native and spines. Bluegill are not highly until early fall, providing a plenti- to that is raised and sold for vulnerable to largemouth bass preda- ful supply of small forage. In small, pond stocking in much of the south- tion and not easily exterminated from east reservoirs, female bluegill east. The male coppernose bluegill a pond by predators. The fathead spawned an average of five times has a purplish head (jaw and opercles) has many favorable charac- over the season. Small bluegill (about and a copper-colored band across the teristics as a forage species, but is too 1 inch) do not handle well so it is head above the eyes that is prominent vulnerable to to serve as a better to stock larger fingerlings (2+ in the breeding season. Coppernose long-term food source. Fatheads are inches) initially. To reduce predation, bluegill have been promoted by fish considered a temporary species and additional stockings of bluegill in bass suppliers as a superior sport fish, and their numbers decrease rapidly in ponds should be limited to fish at least a study found that coppernose blue- ponds with bass populations. Fathead 3 to 6 inches long. grew larger than east and west minnows are also too small as adults The body is slab-like, deep and flat- Texas bluegill when grown together in to be good forage for large bass. tened, and the mouth is very small. ponds. Laboratory tests have shown The dorsal (top) fin has a series of 10 that the coppernose bluegill has the Concerns with forage fish (can be 9 to 11) spines in the first half same cold tolerance as native Texas bluegill. Adding new fish species to increase of the fin, followed by the forage base in an established a rounded, soft section. bass-bluegill pond may have un- The bottom fins (pelvic intended consequences. Some fish and anal) also have species compete for the same natural spines. The pectoral foods as bluegill and can reduce the fins are very long and overall forage base instead of increas- pointed. The short, ing it. For example, threadfin and giz- broad ear flap is a solid zard shad feed heavily on zooplank- dark blue to black, and ton and may reduce food resources on fish larger than 2 for young-of-the-year bluegill. Golden inches there is a dark shiners are egg eaters and can reduce splotch at the bottom bass reproduction. It is also impor- of the soft . Bluegill commercial fish feeds. the water temperature exceeds 64 ºF Redear sunfish are (18 ºC), although spawning at 58 ºF considered to be an (14 ºC) has been reported. Adding excellent sport fish. spawning substrate such as wooden pallets or boards to ponds should The redear is found increase fathead minnow production. throughout the south- eastern U.S. (lower The fathead minnow eats a wide Atlantic and Gulf Slope range of plant and matter, drainages) and west as well as . Zooplankton and Redear sunfish into Texas (Mississippi algae are important food items. Fat- River basin up to Indi- head minnows will eat commercial Redear sunfish ana). It has been intro- fish feeds such as the floating pellets The redear sunfish,Lepomis microlo- duced into many other states from fed to catfish. California to Vermont. It is widely phus, is often stocked in combination Fathead minnows are native to a distributed in Oklahoma and Vir- with bluegill. Although it reproduces large portion of from ginia, and there are localized popula- less prolifically than the bluegill and Canada south to Alabama, Texas tions in Kentucky and Tennessee. is not as suitable a forage fish by and New Mexico, although the exact itself, it eats snails and thus aids in Fathead minnow native range is unclear. Widely used reducing the incidence of snail-borne Fathead minnows, as a forage and bait species, fatheads fish parasites (including yellow, white promelas, are also called toughies or are now found in most states in the and black grubs). Common names flathead minnows. A small, pug- continental U.S. for the redear sunfish include shell- headed fish with a thick, cylindrical cracker, stumpknocker and chinqua- Golden shiner body, its normal color is dark olive pin. Reported spawning temperatures The golden shiner, Notemigonus on top shading to a silvery tan below. for redear sunfish vary crysoleucas, is the most common bait widely, with several pub- minnow raised in the U.S. It has a lications indicating that thin, deep body with a triangular redear start spawning at head and a deeply forked tail. The slightly cooler tempera- back is olive green shading to silver tures than bluegill (68 on the sides. Young fish often have a to 70 ºF; 20 to 21 ºC), dark stripe down the side. Breeding while other literature fish may develop a golden cast to the body; the pelvic fins turn a bright indicates the opposite. Fathead minnow The males generally gold (males) or are clear with a gold construct nests in water deeper than fringe (females). The maximum size A color variant, the “rosy red,” was 3 feet and, as with the bluegill, nests is around 12 inches, but most golden developed by Billy Bland Fisheries of are made near each other in colonies. shiners are less than 6 inches long. Taylor, Arkansas. A redear has a compressed, dark Golden shiners scatter adhesive eggs Fatheads usually live less than 3 olive body shading to yellow-green on vegetation or supplied substrates years and adults are typically less or silver on the sides, with dark spots such as hay. No care is given to the than 3 inches long. In the south, (mottling) and sometimes vertical young. Spawning starts in the south fathead minnows can reach sexual bars, especially on younger fish. The about mid-April at 68 ºF (20 ºC) and maturity in less than a year and mouth is small. The short opercu- fish spawn periodically until water minnows hatched in the spring may lar (ear) flap is black with a white temperatures exceed 81 ºF (27 ºC), spawn in late summer. Males select border and a red to orange spot on typically around the end of June. In the undersides of hard surfaces as the tip. The pectoral fins are long and one study, a pound of golden shiner nests. During spawning, the adhesive pointed; the first dorsal fin has 10 brooders was found to produce an eggs are pressed up against the “ceil- spines and 10 to 12 soft rays. ing” of the nest where Redear preferentially feed on snails they stick and remain to and small mollusks, but will also be cared for by the male consume insect larvae and large during incubation. In- zooplankton. Small amounts of veg- dividual females spawn etation and detritus (decomposing or- frequently, about twice ganic matter) are also eaten. Because a week, during much they feed on the pond bottom, redear of April, May and June. sunfish are less likely to consume Spawning starts when Golden shiner average of almost half a million eggs perature are particularly hard on the of the eye that is not found in thread- over the spawning season. fish. For this reason, threadfin can fins. The fins of the threadfin usually overwinter in deeper reservoirs and have a yellowish tint, and the tail fin While the principal food of golden large rivers in more northerly loca- is often distinctly yellow. The chin shiners is zooplankton (e.g., water tions, but are less likely to survive in and the floor of the mouth of the fleas and other tiny ), they ponds. The native range of thread- threadfin have black specks, while will feed on many other food items fin shad is the southern half of the there are none on the gizzard shad. such as insects, algae, snails and Mississippi River Basin; portions of small fish. Golden shiners readily ac- Threadfin shad spawn starting at 67 Alabama, Mississippi, Tennessee and cept commercial fish feeds. to 70 ºF (19 to 21 ºC) and broadcast Texas; and much of Florida. The spe- adhesive eggs over vegetation and Golden shiners are native to the east- cies has been widely introduced into woody debris. Prolific spawners, ern half of the U.S. and have been reservoirs and lakes throughout the shad mature in less than 1 year and widely distributed throughout much Southeast. produce large quantities of eggs. The of the rest of the country as a forage Shad are in the family; most length of the spawning season is vari- or bait species. Although they feed members of this silvery, slab-sided able and spawning can occur over a primarily by sight, golden shiners family live in the . Shad have a broad temperature range. tolerate -rich ponds and are sharp, saw-toothed ventral keel (ridge found in a wide variety of . Suppliers of threadfin shad may along the belly), shiny scales, and a Given their small size as adults, their catch them from the wild, as juvenile deeply forked tail. It is important to high fecundity, and their omnivo- threadfin form schools, but threadfin distinguish between the “look-alike” rous food habits, golden shiners are are usually mixed together with giz- threadfin shad and the gizzard shad, considered an excellent forage spe- zard shad. Favorite locations to find as normally only the threadfin is suit- cies despite the fact that they eat fish abundant shad populations include able for pond stocking. Gizzard shad eggs. In ponds with largemouth bass areas below dams and wastewater are considered a problematic species a golden shiner population usually treatment facilities. When purchasing because they grow too large to serve is not sustainable, so they must be threadfin shad, be sure to check the as forage for most predatory fish, and restocked periodically. fish carefully to be sure they are all large numbers of big gizzard shad can threadfins. Also insist on a fish health accumulate in ponds, interfering with Threadfin shad inspection, as shad can carry numer- the production of other species. Pro- Threadfin shad, Dorsoma petenense, ous diseases. Shad are delicate and fessional pond management services are used as forage fish because they difficult to transport, so some losses will stock gizzard shad under certain remain relatively small, usually less are to be expected. than 7 inches. Threadfin are a school- specific conditions to promote trophy ing, open-water fish and grow well in bass production, but as a general rule Tilapia productive ponds. Shad are filter- gizzard shad are to be avoided. Tilapia is the common name for a feeders and feed mainly on zooplank- Threadfin and gizzard shad both have number of tropical cichlids. Nile ton and some larger . a thread-like filament at the end of tilapia, Oreochromis niloticus, blue the dorsal (top) fin, tilapia, Oreochromis aureus, and so this thread-like fin Mozambique tilapia, Oreochromis does not distinguish mossambicus, are the most com- the threadfin. The best mon species in the South. These way to tell the two are exotic, non-native fish widely species apart is that considered to be nuisance species, the upper jaw of the and many states regulate or prohibit gizzard shad extends them. It is essential to check with beyond the lower jaw your state Natural Resources Depart- Threadfin shad and has a deep notch ment before obtaining any of these in the center. The fish. Remember that fish stocked into Larger threadfin may consume some upper jaw of the threadfin does not your pond can and will escape into detritus as well. They eat fish feed extend beyond the lower jaw and it natural waters. only incidentally. is not notched. Both species have a are deep-bodied, spiny fish Threadfin do not survive in cold wa- dark spot on the shoulder, although resembling native sunfish, but they ter and usually die in winter outside it is typically darker on the gizzard are and typically die of the deep South and Florida. High shad. Another difference is that the when the water temperature drops mortalities occur at 45 ºF (7 ºC), gizzard shad does not have any yel- below 50 ºF (10 ºC) for long peri- and most fish die at 40 ºF (4.4 ºC). low on the fins, although it may have ods. However, they thrive in warmer Abrupt decreases in water tem- a distinctive yellow spot in the white waters in Florida and will overwinter Other species your pond. Be sure to check with Other fish species such your state Department of Natural as silversides (e.g., Resources to ensure that the fish inland silversides, Mis- species you plan to stock are legal sissippi silversides and in your state. brook silversides), spot- 2) Purchase fish from a reputable tail and emerald shin- source and insist that fish have a ers, rainbow and health inspection. Farm-raised fish lake chub have been are recommended. Fish from the tested or introduced wild can introduce diseases and Blue tilapia as forage in certain parasites into your pond and ship- regions or states. These ments of wild fish often contain where there are thermal refuges, such species are gener- other fish species. These “hitch- as natural springs or heated effluents. ally not raised on farms and little is hiker” and “look-alike” species can Tilapia build circular nests along known about their usefulness as for- ruin the fishing in your pond. pond edges and are considered an age. Blueback herring and are 3) Use care in transport and stocking. aggressive species that out-competes sometimes listed as forage species, Follow recommendations to slowly native fish species for breeding space. but they are widely considered to be acclimate fish, giving them time to adjust to the pond water tem- A major advantage of tilapia is that aquatic nuisance species and many perature and differences in water they spawn frequently throughout states prohibit their possession. Com- chemistry. the summer and then become easy mon fingerlings, either the wild 4) A number of these forage species prey in the fall as water temperatures type or ornamental Koi, are also used will not be able to maintain repro- drop and the tilapia become sluggish. as forage, primarily by commercial ducing populations in farm ponds Tilapias are mouth-brooders; the or government . Stocking under intensive bass predation and female picks up fertilized eggs and into farm ponds is not will need to be restocked periodi- incubates them in her mouth. The recommended, as carp will muddy cally. number of eggs that can be reared the water with their feeding and (typically 300 to 1,200 per clutch) is compete for fish feed. Goldfish are limited by the size of the female’s also used as a forage species, but as Acknowledgement with common carp, they are prohib- mouth. Thus, although they spawn This publication is a revision of the ited in some states. Goldfish are a frequently, relatively few offspring original by Billy Higginbotham, Texas disappearing species in farm ponds, are produced at one time. AgriLife Extension, The Texas A&M as the eggs and fry are consumed by System. Tilapias are very tolerant of low young bluegill. In general, stocking oxygen conditions and will thrive in any of these other species for for- ponds with heavy plankton blooms. age is not advisable, and they should Photographs Blue-green algae are common dur- never be stocked without the consent Photographs are by Chad Thomas, ing the summer in nutrient-rich, of your state Department of Natural Texas State University Biology De- eutrophic waters with dense algae Resources. partment/Aquatic Station and are blooms and surface scums. Though from: omnivorous, Nile and blue tilapia feed on planktonic algae and, unlike Summary Thomas, C., T. H. Bonner and B. G. most native fish species, can digest Key considerations in selecting and Whiteside. 2007. Freshwater fishes of blue-green algae. Thus, these tilapia stocking forage fish: Texas: a field guide. Texas A&M Uni- species can exploit a food source that 1) Obtain knowledgeable advice on versity Press, College Station, TX. is unavailable to other fish. appropriate forage fish species for SRAC fact sheets are reviewed annually by the Publications, Videos and Computer Software Steering Committee. Fact sheets are revised as new knowledge becomes available. Fact sheets that have not been revised are considered to reflect the current state of knowledge.

The work reported in this publication was supported in part by the Southern Regional Aquaculture Center through Grant No. 2006- 38500-16977 from the United States Department of Agriculture, Cooperative State Research, Education, and Extension Service.