Outlook for Yellow Perch, Walleye and Sauger Culture in Kentucky

Forrest Wynne, Aquaculture Extension Specialist, Kentucky State University Cooperative Extension Program, Graves County Cooperative Extension Service Office, 251 Housman Street, Mayfield, KY 42066-1165 Telephone: (270)247- 2334 FAX:(270)247- 5193 e mail: [email protected]

Introduction culture operations may produce these fishes in water-warming ponds as a In North America, the economically supplemental crop. Other surface and important members of the perch family groundwater resources may be suitable (Percidae) include the walleye for coolwater fish production. (Stizostedion vitreum vitreum), sauger Coolwater species consume large (Stizostedion canadense), and the yellow numbers of fish in the wild. Intentional or perch (Perca flavescens). Members of accidental introductions of any fish may the pike family (Esocidae) are also destroy resident fish populations or important sport-fishes in the United States interfere with current management and Canada. The life history and culture programs. Contact the Kentucky techniques for esocids are described in Department of Fish and Wildlife the article "Outlook for Muskellunge, Resources or a Kentucky State University Northern Pike and Chain Pickerel Culture Aquaculture Extension Specialist before in Kentucky (SKY-583)." Members of the stocking any fish into private waters. perch and pike families are often described as "coolwater" fishes. These Distribution and Life History fishes thrive at water temperatures which of the Walleye range between 64 to 77 degrees F

(Kendall 1978). Generally, these water Walleye populations occur in streams, temperatures are considered too warm to rivers and reservoirs throughout Kentucky allow the survival of most coldwater fishes (Burr and Warren, 1986). The walleye is (trout and salmon), and too cold to permit confined to the freshwaters of North the optimum growth of warmwater fishes America (Scott and Crossman, 1973). (catfish and sunfish). Walleye spawn in spring when water Walleye, sauger and yellow perch are temperatures range from 48 to 55 highly regarded as food and sport-fishes. degrees F (Piper et al. 1989). The fish Review of the literature suggests the spawn on rocky substrates below walleye and walleye (female) - sauger impassible falls, in river tailwaters behind (male) hybrid may possess the most dams, or on lake shoals. Spawning potential for commercial aquaculture. occurs at night. The eggs of the larger Kentucky coolwater fish production will females are fertilized by the smaller likely be limited by warm summer water males. temperatures (> 90o F). Spring-fed trout A female walleye, 31.5 inches long, eggs are released, they sink into rock may contain 612,000 eggs. After the crevices. Walleye eggs will hatch in 1 to 3 weeks depending on water temperature Broodfish are caught in rivers with fyke (Stickney, 1993). Fry may begin feeding trap nets, gillnets or by electrofishing at prior to absorption of the yolk sac. Ten to night. Mature females will have swollen fifteen days following hatching, the abdomens and red colored vents which walleye fry disperse into open water turn purple as the eggs mature. The where they feed on invertebrates and broodfish are transported to a hatchery larval fish near the surface. Invertebrates where they are anesthetized. Eggs are may be the most important food source stripped from the females into a dry pan, for fry particularly in the spring and early by hand. Milt from male fish is added to summer. Cannibalism may occur among the eggs. larger fry if insufficient food, such as the The eggs and sperm are mixed and left fry of yellow perch, is not available. to fertilize for 5 to 15 minutes. Walleye Walleye appear to feed on any species of eggs are adhesive. This may cause the fish. The young may reach 3 to 8 inches eggs to cluster and suffocate during long after the first growing season. Males incubation if they are not properly generally mature after reaching a length separated (Piper et al. 1989). Tannic acid of 12 inches, or 2 to 4 years of age. may be used as an initial rinse for Females mature at lengths of 14 to 17 fertilized eggs. The eggs are then placed inches, or 3 to 6 years of age in the in a 400 mg/l bath solution for 2 to 3 southern United States. Walleye live from minutes. In approximately 1 to 2 hours, 10 to 12 years and females may reach 25 the eggs will "water harden." Water lbs (Scott and Crossman, 1973). hardening occurs when the egg absorbs Walleye are sight predators and prefer water between the shell and the yoke. turbid, shallow lakes where they school Water hardened eggs will feel firm when near the bottom. These fish have a layer touched. The water must be exchanged of the eye (Tapetum lucidum) which at least once every hour before the eggs gathers light and is extremely sensitive to are rinsed and transferred into 1 gallon bright light. While walleye fry are hatching jars. Water flows, adjusted attracted to light, adult fish usually feed in between 1 to 1.5 gallons per minute, are dimly lit zones or at night. The fish feed used to create a gentle rolling movement actively throughout the year. Northern in the hatching jars. Generally, 75% of jar pike, yellow perch, sauger, smallmouth volume is filled with eggs (approximately bass, and lake whitefish may prey upon 30,000 - 35,000 eggs per liter). The eggs young walleye and compete with them for will hatch in about 10 days at 55 degrees food (Scott and Crossman, 1973). F. Hatching success of 50 to 70% is common. Yolk absorption occurs in 3 or Culture of Walleye more days after hatching, depending on water temperature. Walleye fry must have Walleye culturists depend on eggs taken access to adequate food within 3 to 5 from wild fish to stock their hatcheries. days of hatching (Stickney, 1993). Walleye have been reared intensively rearing fry (Stickney, 1993). Currently, in raceways, tanks and troughs; however, most walleye fry are cultured in fertilized the fry do not readily accept artificial feed ponds which support abundant natural and mortality is often high (Kendall 1978). food. Survival to the fingerling stage These culture systems have not been using traditional pond culture techniques proven to be economically feasible for is unpredictable. After the fish reach 1 inch long and will accept artificial food, growth. Automatic feeders, set at 2 to 10 they may be moved to a more intensive minute intervals, should offer food to culture environment (Stickney, 1993). walleye for a minimum of 16 hours per Small ponds (1 to 5 surface acres) day. Initially, the fingerlings should be fed should be drained, dried and than re-filled 10% of their body weight daily. For in less than 14 days to minimize intensive production units, one or two predacious aquatic insect populations water exchanges per hour at water which eat the fry. Where draining is not temperatures of 68 degrees F is practical, pond water must be treated with recommended. Upwelling current inside rotenone to eliminate other fish. Surface the tank, will be required to keep the fine water should be filtered to prevent the food particles available to the walleye. As introduction of predators into the pond. the fish feed more actively, offer food at 3 The ponds should be fertilized after filling to 6% of their body weight daily. to promote zooplankton food for the fry. Cannibals should be removed. Walleye Inorganic fertilizers, high in phosphorus, grow quickly and require frequent grading or organic fertilizers such as bone meal, (Stickney, 1993). alfalfa, or manures are commonly used to Typically, 1 to 3 inch long walleye stimulate plankton blooms. Dense fingerlings are produced in ponds. When plankton blooms will also help prevent the sufficient food is available, fingerlings may establishment of unwanted plants and be harvested after 4 to 8 weeks. algae in the pond (Harding et al. 1992). Fingerlings should be harvested when Walleye fry are transferred to earthen water temperatures are less than 68 ponds when they are 2 to 5 days old. The degrees F (Harding et al. 1992). If larger fish must be acclimated to the pond's fish are desired, minnows should be water temperature, 30 minutes for each 2 stocked into the ponds when the walleye degree F difference in water temperature are approximately 1.5 inches long. To (Harding et al. 1992). Dissolved oxygen produce 4 to 6 inch long walleye, small levels should remain at 5 mg/l or greater, fingerlings may be stocked at 10,000 to throughout the culture period. Walleye fry 20,000 fish per surface acre. If 6 to 8 inch have been found to grow larger and faster long walleye are to be grown, small fish in water with high calcium and can be stocked at approximately 5,000 to magnesium hardness, as opposed to soft 10,000 fingerlings per acre. To produce water. Typical stocking densities for walleye fingerlings 8 inches long or walleye fry range between 20,000 and longer, fish should be stocked at less than 50,000 fry per acre foot of pond volume 4,000 per acre (Piper et al. 1989). (Piper et al. 1989). Once harvested, walleye fingerlings Walleye fingerlings must be trained to may be stocked into intensive fish culture accept artificial food. Diets such as the systems. However, economical methods W14-16 series developed by the U.S. of intensively culturing large walleye have Fish and Wildlife Service or the Abernathy not yet been demonstrated. Harvested salmon diet, contain 50 to 60% protein fish should be placed in a 0.5% salt and which is composed of 60 to 80% animal bacteriostatic solution during transport protein. Low intensity lighting, providing (Stickney, 1993). 16 hours each day, enhances feeding and Walleye fingerlings could be sold to private lakes. Larger fish may provide Kentucky sportsmen's clubs for stocking some small impoundment owners an alternative predator species. Adult species are not considered economically walleye could support a food-fish market, important. Northern pike and walleye provided large fish production techniques likely compete with sauger for food. become more reliable and economical. Predators and cannibalistic behavior Distribution and Life History of probably account for most natural sauger mortality (Scott and Crossman, 1973). the Sauger

Sauger and walleye occur in similar Culture of Sauger habitats throughout Kentucky. However, the sauger appears to be tolerant of more Literature about the culture of sauger is turbid waters than walleye (Burr and limited. Under intensive culture Warren, 1986). The sauger's preferred conditions, the walleye female - sauger habitat seems to be large shallow lakes male hybrids grew faster, were less which have turbid waters (caused by aggressive and were less affected by suspended clay particles) or turbid, large, handling stress than either parent slow-moving rivers. The sauger occurs species. Hybridization did not influence solely in the fresh waters of North egg survival or the rate of hatching for America (Scott and Crossman, 1973). either species. Hybrid fingerlings Sauger spawn in the spring when water accepted artificial feed and were not as temperatures are between 39 to 43 aggressive towards one another as were degrees F. Spawning occurs at night on the purebred fishes. The hybrid fish gravel shoals. Often, sauger spawn gained weight nearly twice as fast as immediately after the walleye and in the walleyes. There is also evidence which same locations. In some instances, suggests this hybrid may reproduce. As walleye and sauger hybridize. Sauger with the walleye, potential hybrid eggs are semi-buoyant and fall into fingerling and food-fish markets could be substrate crevices following spawning. A established. Advancements in the female will lay 15,000 to 40,000 eggs for production technology of these hybrids each pound of her body weight. The eggs will be required for profitable commercial will hatch in 25 to 29 days when water fish production to occur in the future. temperatures range between 40 and 55 The reciprocal hybrid (sauger female x degrees F. Fry feed on zooplankton and walleye male) did not display improved aquatic insect larvae. Sauger fry will growth and production characteristics as begin consuming other fish when they compared with the parent species. reach 0.5 inches long. Juvenile sauger Purebred sauger had more injuries than may reach 3 to 6 inches long after the first either the walleye or the hybrids which growing season. Female sauger may may indicate more aggressive behavior reach 19 inches long and weigh 3 lbs. within this species. Additionally, purebred Male fish mature at 2 to 3 years, while sauger grew slower than walleye or either females mature at 4 to 6 years of age. of the hybrids (Malison et al. 1990). Sauger generally live 5 to 6 years in the southern United States (Scott and Distribution and Life History of Crossman, 1973). the Yellow Perch Like walleye, sauger are sight predators. Adult sauger prey upon a wide variety of small fishes. Most of these Yellow perch occasionally appear in the inches long, may contain 109,000 eggs. Ohio River, bordering northern Kentucky, Young perch will grow 1 to 4 inches long and have been stocked in some lakes in during their first summer, feeding on south-east Kentucky (Burr and Warren invertebrates and fish. Feeding occurs 1986). This fish is common in lakes, during the morning and evening hours, ponds and quiet rivers of the Midwest, rarely at night. Yellow perch will feed Atlantic Coast, and Canada. The yellow throughout the year, even under ice. perch is a schooling fish and is Perch will consume the eggs and young commercially caught in the Great Lakes of a wide variety of fishes. They may (Scott and Crossman, 1973). compete for food with brook trout, black Approximately 75% of these fish are basses, crappie and bluegill (Scott and consumed in the State of Wisconsin. The Crossman, 1973). yellow perch is an important gamefish in Yellow perch can adapt to diverse much of North America (Stickney 1993) habitats and are tolerant of low dissolved however, it is not considered desirable in oxygen. Preferred water temperatures the southern United States (Kendall have been experimentally determined to 1978). range between 70 and 77 degrees F. Yellow perch spawn in spring when Perch have a high reproductive rate and water temperatures are between 44 to 54 their populations frequently become degrees F. Spawning occurs at night or stunted (Scott and Crossman, 1973). during early morning. Semi-buoyant eggs Extensive stocking programs released are contained in a gelatinous, folded millions of yellow perch in the early 1900's string or tube and are most likely fertilized (Stickney 1993). Currently, few stocking by several males. The egg tube is programs are still in existence. Some released from the female and adheres to states in the north-east and Pacific United rooted vegetation, submerged brush, States have expressed interest in limiting sand or gravel substrate. The eggs or removing yellow perch populations receive no care, but apparently contain a because they compete for food with substance which discourages predation salmonids. Often, yellow perch grow by other fishes. The eggs hatch in slowly and to a small size (Kendall 1978). approximately 8 to 10 days (Scott and Crossman, 1973). Females grow faster and larger than Culture of Yellow Perch males, but rarely exceed 14 inches or weigh more than 1 lb. A female fish, 10 Information about the culture of yellow yellow perch fingerlings cultured can be perch is limited. However, the biology of trained to accept pelleted food. The this species is similar to the walleye. training program must include the Typically, yellow perch are harvested at elimination of natural foods, elevated 1/4 to 1/3 lb and are 8 to 10 inches long. water temperatures (68 to 75 degrees F) Like the walleye, perch fry will not readily and frequent feeding and grading to accept artificial feeds until they are reduce cannibalism. Fingerlings may be approximately 3/4 of an inch long. Fry are reared in tanks or ponds (Stickney 1993). reared in fertilized ponds and can be Automatic feeders, which dispense small harvested by lift nets at night when amounts of feed at frequent intervals, are attracted to light. Approximately 80% of recommended for rearing yellow perch in tanks and raceways. "Training" yellow The economics of yellow perch culture perch fingerlings to feed in specific pond as food-fish does not appear practical. locations is recommended, as opposed to Contributing factors would include, high broadcasting feed over the entire pond production costs (fingerlings and feed), surface (Kendall 1978). competition from commercial catch, small Yellow perch have been reared in size (particularly males) at harvest, and Wisconsin ponds. Broodstock were low dress-out yields of approximately 42% obtained by ice fishing, and non-induced for fillets (Stickney 1993). spawning took place in a metal tank. Average weight of female fish was less REFERENCES than 1.5 ounces, while males weighed less than 0.5 ounce. Plastic spawning Burr, B. M. and M. L. Warren, Jr. 1986. A mats and vertical fencing were placed on Distributional Atlas of Kentucky Fishes. the tank bottoms as spawning substrate Kentucky Nature Preserves Commission for the egg envelopes. Most eggs were Scientific and Technical Series Number 4. deposited when water temperature was 50 degrees F. Eggs were placed in trout Harding, L. M., C. P. Clouse, R.C. hatching troughs and in a vertical tray Summerfelt, and J. E. Morris, 1992. Pond incubator. Water flow rates were adjusted Culture of Walleye Fingerlings. North to range between 1 and 2.5 gallons per Central Regional Aquaculture Center, minute. Formalin was used to control Fact Sheet Series #102. fungal growth on eggs (Kendall 1978). Average time to hatch was 18.5 days Kendall, R. L. Editor, 1978. Selected with a water temperature of approximately Coolwater Fishes of North America. 51 degrees F. After several fry hatched, American Fisheries Society Special the eggs were transferred to floating Publication No. 11. screens placed in a rearing pond. Floating screens were anchored in a Malison, J. A., T. B. Kayes, J. A. Held and shallow, 0.5 surface acre pond. The 0.25 C. H. Amundson, 1990. Comparative inch mesh permitted the fry to pass Survival, Growth, and Reproductive through the screen after hatching. Fry Development and Sauger and Their were first spotted in the pond when Hybrids Reared under Intensive Culture lengths were greater than 0.5 inches. Conditions. Progressive Fish-Culturist Five hundred lbs of hay was used to 52:73-82. fertilize the pond to promote populations of zooplankton to feed the fry. After Piper, R. G., I. B. McElwain, L. E. Orme, approximately 6 weeks, 0.38 g fingerlings J. P. McCraren, L. G. Fowler and J. R. were harvested from the pond. Survival Leonard, 1989. Fish Hatchery was 35% from the egg stage to 0.38 g. Management. United States Department Fingerlings were fed a commercial trout of the Interior Fish and Wildlife feed. Some fish were transferred to a Service, Washington D.C. circular tank with water temperatures held at 61 degrees F. Thirty-eight percent of Scott, W. B. and E. J. Crossman, 1973. these perch survived and grew to 1.36 g Freshwater Fishes of Canada. Fisheries average over a two month period (Kendall Research Board of Canada, Ottawa. 1978). Bulletin 184.

Stickney, R. R. 1993. Advances in Fisheries Science: Culture of Nonsalmonid Freshwater Fishes. Second Edition. CRC Press, INC.