Raising Yellow Perch

62 THE ADVOCATE DECEMBER 2000

Bill Manci, C.F.S.

Fisheries Technology Associates, Inc.

Fort Collins, Colorado, USA

While other species progressed to commercialization in the United States faster than yellow perch (Perca flavescens), the move to bring the fish to commercial status is well founded.

The characteristics of yellow perch compare well with those of more commonly cultured species.

Market

During the 1950s and 1960s, yellow perch harvests from the North American Great Lakes exceeded 15 million kg per year, and markets readily absorbed those supplies. Then wild harvests declined to the range of 5 million to 8 million kg per year or less during the 1980s and 1990s. Most fisheries biologists predict the peak wild harvests will never return. Today, the aquaculture industry is adding to the supply, but contributes less than 90 mt annually. Aquaculture products may have a marketing advantage over wild-caught products because of their superior freshness, and concerns over microcontaminants In wild-caught products from the Great Lakes and elsewhere.

Compared to Other Species, Yellow Perch:

Grow rapidly to a large size.

Yellow perch grow more slowly than other cultured species. However, the market size for yellow perch (115 to 150 g, whole fish) is consistently smaller than for most other cultured food fish, so the required growout times tend to be shorter than they would be if the market demanded larger fish. Good management practices play important roles in maximizing the growth potential of yellow perch and most other fishes.

Reach market size before reaching sexual maturity.

Yellow perch rely on environmental cues – specifically, decreasing photoperiod and temperature – to trigger gametogenesis. In the absence of these cues, such as in environmentally controlled growout systems, gametogenesis and a subsequent attenuation in somatic growth are not issues, and maximum somatic growth can continue unabated. In time, some believe that genetic selection and manipulation will produce yellow perch that display postponed sexual maturation.

Readily accept a formulated diet.

Yellow perch are no less likely to accept artificial feeds than other cultured species after reaching a size of 50 mm TL. First feeding (as discussed below) can be problematic, but the fish feed vigorously on formulated diets and perform well, even on diets not specifically designed for yellow perch.

Feed fairly low on the food chain.

Yellow perch feed low on the food chain, with a diet in the wild that consists of zooplankton, insects, and other benthic organisms, with only occasional small fishes. The optimal dietary crude protein requirement for yellow perch is in the range of 21 to 27%, suggesting that relatively lowcost diets will produce acceptable production results.

Not cannibalistic.

With respect to cannibalism, yellow perch behavior is relatively benign, both on an absolute basis and certainly relative to many other cultured species. Professionals cite good management as a key factor in minimizing cannibalism, regardless of species.

Fairly disease resistant.

Yellow perch are by no means “bulletproof” with regard to disease. However, they are no more susceptible to disease than other species listed in Table 1. Production system management plays a very important role in the nature, frequency, and severity of yellow perch disease outbreaks, as it does with all cultured species.

Handle well.

The consensus of experts is that the tolerance of yellow perch to handling is no less than, or comparable to, most other species listed in Table 1, with the possible exception of tilapia.

Prospects for Yellow Perch Aquaculture PRODUCTION

Illustration courtesy of New York Sportfishing and Aquatic Resources Education Program

(SAREP), Cornell University, New York, USA.

THE ADVOCATE DECEMBER 2000 63

Produce offspring large enough to accept pelleted feeds at first feeding.

Developing acceptable first feeds for yellow perch has been challenging and a subject of ongoing research. However, evidence suggests real progress in habituating earlyfingerling yellow perch (less than 15 mm TL) to artificial diets.

Easily cultured under high rearing densities.

Research has shown that yellow perch thrive under rearing densities and flow indexes that compare favorably to those tolerated by rainbow trout and salmon, perhaps because in nature they are a strongly schooling fish.

Tolerant of poor water quality.

My own research on ammonia and nitrite toxicity in yellow perch, and the research of others relative to oxygen tolerances, indicate that yellow perch show excellent tolerance to low water quality. Compared to rainbow trout and Atlantic salmon, yellow perch display a high tolerance to ammonia and nitrite, and an increased tolerance to low levels of dissolved oxygen.

Market value that exceeds production costs.

The current financial success enjoyed by a significant number of private-sector producers must be seriously considered. System scale, size, and design are crucial elements in determining the long-term financial success of yellow perch aquaculture facilities, as well. Yellow perch have a high market value compared to catfish, trout, and other freshwater species that are successfully cultured.

Additional Ideal Culture Characteristics

The following traits are also extremely important and worthy of inclusion in a table of ideal culture fish characteristics.

Eggs/fry easily produced from captive fish.

Yellow perch will spawn in tanks as well as ponds, or may be hand-stripped of eggs and sperm, producing large quantities of each. Using a variety of spawning methods, fertilization rates can exceed 90%.

High yield of edible flesh.

Ayellow perch processor indicated that his company realizes an average yield for all yellow perch of 45%, regardless of their sex or reproductive status, which is significantly higher than that of tilapia or catfish. Most yellow perch processors obtain yields of 43 to 52% for sexually immature fish and 35 to 43% for sexually mature fish of both sexes.

Flesh freezes and stores well.

Yellow perch flesh freezes and stores well.

Tolerant to wide range of temperature.

While optimal temperatures for yellow perch growth fall in the range of 21 to 24º C, yellow perch routinely survive water temperatures down to freezing. The upper limit of their temperature tolerance is reported to be over 33º C.

Tolerant to wide range of salinity.

The range of yellow perch in the wild includes estuaries such as the Chesapeake Bay in eastern USA, where salinity is highly variable and can range from 0 ppt to that of fullstrength seawater. Physiologically, yellow perch are relatively adaptable.

Good profitability.

In 1986, prices for yellow perch fillets sold at the retail level were U.S. $8 to $17.50 per kg. In 1999, they rose to U.S. $19.84 to $33.07 per kg. A researcher developed a model for a 22,727-kg-per-year water-recirculating production system for yellow perch and calculated a “break-even” operating cost of U.S. $5.68 per kg for fish in the round. This translates to U.S. $12.62 per kg for fillets, assuming a 45% yield.

Conclusion

Successful yellow perch aquaculture requires skill and experience, a thorough understanding of the animal’s biology and temperament, and (most importantly) appropriate technical and business management. Often the management components of a system are secondary in the planning process – an error that can ultimately lead to failure. Half-hearted, but good-intentioned attempts have tarnished what would otherwise be a good record for yellow perch. While the challenges are real, success is attainable and demonstrable. The rewards, both professional and financial, are real as well.

Spawning female yellow perch (Perca flavescens) and trailing egg ribbon.

yellow perch

Perca flavescens

Kingdom: Animalia

Division/Phylum: Chordata - vertebrates

Class: Osteichthyes

Family: Perciformes

Order: Percidae

Features

The yellow perch has a deep body flattened side to

side. The sides are bright yellow to brassy green with

seven dark, vertical bars. The back is olive green and

the belly is light. The dorsal fin is completely

separated into spiny and soft portions. It appears

somewhat humpbacked. Its average size is onefourth

to one-half pound and six to 12 inches long.

The state record in Iowa was just under two pounds.

Natural History

The yellow perch is essentially a lake fish and is most

abundant in natural lakes. It is less common in rivers,

with the exception of the Mississippi. It feeds in the

morning and evening and rests on the bottom at

night. It eats fish and insects. Young school near

weedy areas, but larger fish usually prefer deeper

water. It reaches maturity at one to two years and

spawns in April and May. The female spawns 10,000

to 40,000 eggs depending on her size. The ribbon-like

masses of sticky eggs are deposited over sand bars,

plants, brush, or other materials. Many are eaten by

other fish, washed ashore, or stranded by low water.

Eggs hatch in 12 to 21 days. The yellow perch has an

average life span of seven to eight years.

Habitats

Mississippi River; natural lakes and prairie marshes;

constructed lakes, ponds, and reservoirs; interior

rivers and streams

Iowa Status

common; native

Iowa Range

statewide

Bibliography

Iowa Department of Natural Resources. 2001.

Biodiversity of Iowa: Aquatic Habitats CD-ROM.

YYellow Perch

.Teaching Plan:

Module Yellow Perch - Section E

Problem Area: Describing Feeding Habits of Yellow Perch

Goal: The goal of this problem area is to understand the dietary requirements and

feeding techniques used in raising Yellow Perch as an aquaculture crop.

Learning Objectives: Upon completion of this section, student will be able to:

describe the natural feeding characteristics of Yellow Perch

explain factors determining food selection of Yellow Perch

Instructional Resources:

Essential:

The Biology of Perch and Related Fish, by Craig, J.F., Croom Helms, London., 1987.

"Use of Animal Fat in Formulated Diets for Yellow Perch," by Heck, N.E. & Calbert, H.E.,

University of Wisconsin, 1977.

Aquaculture Curriculum Guide

Content and Procedures

Preparation (Interest Approach):

To develop student interest in this module, buy two or three varieties of commercial fish food.

Compare the ingredients of these foods. Experiment with the various foods to see whether the

fish prefer one over the other.

Preparation:

A. What natural foods do Yellow Perch eat?

Show TM E1 and lead a discussion about the natural food diet of Yellow Perch.

1. Energy inflow/outflow is a complicated process.

2. Perch eat almost anything, but are primarily zooplankton eaters, particularly from May

to September.

3. Exogenous feeding commences with immature copepods and rotifers. Feed on

cladocerans when they get larger

4. Are quite cannibalistic when young are abundant.

5. Walleye feed on Perch fry.

B. How do the Yellow Perch select food?

Show TM E2 and lead a discussion about the food selection of the Yellow Perch.

1. Size of mouth determines size of prey.

2. Movement of prey is important.

3. Yellow Perch are primarily shoaling (travel in schools) predators.

4. They feed actively in day time.

5. Peak feeding is at sunrise and sunset.

6. Perch are inactive at night, spending that time on the lake bottom in shallow water.

7. Spend winter in deep water.

8. Fry are positively phototactic; they feed almost continually during the day on

zooplankton.

C. How do the Yellow Perch feed?

Show TM E3 and lead a discussion about the feeding procedures for

commercially raised Yellow Perch.

1. Perch display "shy feeding behavior" and must be trained to overcome this.

2. After fingerlings reach 18 mm, 80% can be trained to accept prepared diets.

3. Training procedure similar to that of striped bass.

4. Procedure includes:

a. Concentrating the fingerlings.

YYellow Perch

b. Gradually removing natural food source.

c. Elevating the temperature to insure aggressive feeding response.

d. Feeding frequently.

e. Grading fingerlings to eliminate cannibalism.

4. Some growers initiate feeding with a soft pellet (Oregon Moist), then switch to hard

pellets.

5. Others start with hard pellets, which are cheaper.

6. Fingerlings can consume pellets between 0.84 and 1.19 mm in diameter.

Review:

Review by having students demonstrate their knowledge and understanding of the objectives

for this problem area. Lead a discussion with students by asking questions that cause them to

explain the content that goes with each objective.

Evaluation:

Evaluation will be based on class participation, quizzes, and a final exam.

Aquaculture Curriculum Guide

TM E1

Natural Foods Yellow Perch Eat

• Are primarily zooplankton eaters

• Exogenous feeding commences with

immature copepods and rotifers

• Are cannibalistic when young

• Perch fry are food source for walleye

YYellow Perch

TM E2

Food Selection of Yellow Perch

• Determined by size of mouth

• Movement of prey is important

• Perch are shoaling predators

• Fry feed almost continually during the

day on zooplankton

• Peak feeding at sunrise and sunset

spend winter in deep water

Aquaculture Curriculum Guide

TM E3

Feeding Procedures for

Yellow Perch

• Concentrate the fingerlings

• Remove natural food source

• Elevate the temperature

• Feed frequently

• Grade by size

• Initiate with soft pellets

YYellow Perch

Quiz for Section E

Name:

Date:

Quiz on the Feeding Habits of Yellow Perch.

Circle a T if it is a True statement or an F if it is a False statement .

1. T F Yellow Perch are daytime feeders.

2. T F Perch are individualistic and seldom travel in schools.

3 T F In switching to commercial feeds, it is best to feed Yellow Perch only occasionally.

4. T F Young Perch feed primarily on zooplankton.

5. T F Diet is determined by the size of the mouth.

6. T F When switching to commercial feeds, it is best to lower the water temperature.

7. T F Peak feeding is at sunrise and sunset.

8. T F Yellow Perch are often cannibalistic when young.

Aquaculture Curriculum Guide

Key for Quiz - Section E

1. T Yellow Perch are daytime feeders.

2. F Perch are shoaling predators.

3. F In switching to commercial feeds, it is best to feed `Yellow Perch frequently.

4. T Young Perch feed primarily on zooplankton.

5. T Diet is determined by the size of the mouth.

6. F When switching to commercial feeds, it is best to raise the water temperature.

7 T Peak feeding si at sunrise and sunset.

8. T Yellow Perch are often cannibalistic when young.

Yellow Perch

Teaching Plan:

Module: Yellow Perch - Section G

Problem Area: Obtaining Aquaculture Information

Goal: The goal of this problem area is to understand different

techniques used in raising Yellow Perch.

ßLearning Objectives: Upon completion of this section, the student will be able to:

explain the procedures used in a commercial operation

discuss the optimum growth rate of commercially raised Yellow

Perch

explain the pond culture requirements of Yellow Perch

Instructional Resources:

Essential:

The Biology of Perch and Related Fish, by Craig, J.F., Croom Helms, London, 1987.

Culture of Nonsalmonid Freshwater Fishes: Yellow Perch, by Heidinger, R.C., Kayes, T.B.,

CRC Press, Boca Raton, FL, 1986.

Additional:

"Genetic Manipulation of Growth and Production of Select Great Lakes Coolwater Fishes,” by

Kayes, T.B., & Malison, J.A., R/AQ-14, University of Wisconsin - Madison.