Yellow perch are found throughout most of Canada and from Atlantic coast watersheds into the Midwest. Their natural range in the U.S. extends from Maine to northern South Carolina and westward to Missouri and Montana. This species has also been introduced and established in a number of other states with suitable habitats. Yellow perch thrive in cool water lakes, ponds, and slow moving streams and rivers. A prized fish in the Great Lakes region, the Yellow perch has delicate white flesh and excellent flavor. Yellow perch are low in fat, which tends to prolong frozen shelf life of fillets and makes the product more adaptable for different cuisines.
In the Great Lakes, the commercial fishery for Yellow perch reached peak harvests of over 33 million lb. annually during the 1950s and 1960s. The fish was (and continues to be) especially preferred by consumers throughout the Midwest for the Friday night fish fry meals that became a tradition over the past century following World War II. The commercial fishery has declined significantly, with numerous closures and moratoria, while demand has continued in spite of limited supplies.
The fact that Yellow perch is in such high demand has spurred a number of aquaculture researchers to develop production methods over the past several decades. Researchers have established that the fish readily consumes manufactured feeds, tolerates crowding, and is relatively docile at high densities, with minimal cannibalism or aggressive behavior apart from during the nursery phase. However, Yellow perch often reach sexual maturity before reaching a preferred market size, at which point growth slows significantly and feed conversion is much less efficient.
Males can reach sexual maturity at sizes as small as 3 inches, and females at 4 inches. Size disparities between sexes typically become apparent during the grow-out cycle, with males lagging behind females. Research has examined the potential of producing sterile triploid fingerlings to address these issues, but practical and reliable methods are not yet available. Artificial spawning of Yellow perch under hatchery conditions is labor-intensive and challenging. As a result, researchers have focused on optimizing captive spawning methods in order to address a chronic shortage of fingerlings. Recent findings from walleye hatchery research are currently being adapted for Yellow perch.
Spawning begins when temperatures reach 45o to 55o F, with females typically producing 2,200 to 6,600 eggs per ounce of body weight. Off-season spawning can be done in indoor tanks by manipulating photoperiod and temperature, but results have been inconsistent in the past. Hatching takes anywhere from 6 to 50 days, depending on water temperature. Although fry can be raised in tanks using live feeds followed by artificial diets, fertilized hatchery ponds are usually used to raise fry to fingerlings of a size suitable for grow-out. Fingerlings are usually harvested and introduced to tank culture to be trained on feed once they reach 1 to 2 inches in length. Pathogen monitoring and treatment are particularly important considerations when moving fingerlings from open ponds to high-density tanks.
Once trained on artificial feeds, Yellow perch can be raised using a variety of strategies, including raceways, ponds, cages and recirculating aquaculture systems (RAS). Economic feasibility varies from system to system, and over the past several decades many operations have become established only to eventually go out of business. In general, pond culture has provided the highest returns and the lowest risk.
Each production strategy has its own inherent challenges. Effluent-related regulatory issues can complicate efforts to establish and operate raceways, apart from the need to find a location with a reliable water source of suitable quality. RAS facilities involve high fixed and variable costs, and disease problems related to crowding and stress can occur in cage culture. Predation is also a concern in some operations, involving birds such as cormorants and pelicans in pond culture and furbearers such as otters and mink in cage culture.
Optimum growth for Yellow perch occurs at 72o – 75o F, and growth ceases at temperatures of 50o F or below. In more northerly regions, temperatures are below optimum for much of the year. In the southern portion of the Yellow perch’s natural range temperatures are often above optimum throughout the summer months and can occasionally reach lethal limits.
In tank culture, a 16 hr. light to 8 hr. dark photoperiod is preferable to encourage growth. Research suggests that, with proper control over environmental cues that would normally trigger maturation such as photoperiod and temperature, recirculating systems offer the possibility of raising Yellow perch to market size before they begin to mature. However, the seasonal availability of fingerlings can reduce the opportunities to take advantage of this strategy. Although higher levels of protein may be appropriate for fingerling culture, 27% protein grow-out diets have been shown to be optimal for Yellow perch from both biological and economic perspectives.
Grubs, bacteria, nematodes and protozoan parasites can all result in disease losses in open ponds. With the possible exception of grubs similar pathogens can occur in other culture systems if stringent biosecurity measures are not practiced. Combination pond- and tank culture strategies can exacerbate these problems.
The USDA’s 2018 Census of Aquaculture reported a total of 65 farms producing Yellow perch in the U.S. Twelve farms produced foodsize fish, 35 reported sales of stockers (large fingerlings ready for final grow-out) and 29 reported sales of fingerlings or fry. The total farm gate value of Yellow perch sales was $1,104,000, with foodsize fish, stockers and fingerlings/fry accounting for $140,000, $646,000 and $316,000 respectively. Average price per lb. for foodsize fish was reported as $2.62. Ohio led the country in the number of Yellow perch operations, with 15, followed by Wisconsin with 13, and Michigan and Minnesota, each with 8.
The historical demand for Yellow perch has been centered in the Great Lakes region, on both sides of the U.S. Canada border, but demand has continued to grow in a number of other areas. Markets have traditionally required an 8 – 10 inch fish, which requires substantial grow-out time even in RAS operations. Markets generally want scaled fillets, but the costs to process this product form can be extremely high, approaching $3 per lb. or more depending on the volume being handled. Some consumers actually prefer whole gutted fish and fish steaks. Many producers may have access to processors that will take their fish, but some have to find other marketing options. If fish are to be processed on site at the farm, a number of sanitation and environmental regulations must be considered, as well as liability issues.
Historically, Yellow perch producers have utilized a number of marketing channels, including processors, seafood retailers and wholesalers, supermarkets and grocery wholesalers, restaurants, and food service distributors. All of these potential buyers require regular, year-round supplies. Some producers sell advanced fingerlings to stock for recreational fisheries, a market with fewer requirements in terms of constant supply.
Competition exists in the marketplace, but savvy Yellow perch producers have a number of distinct marketing advantages if they choose to use them. Mercury levels in wild Yellow perch have been a concern for several decades, but are not an issue for aquacultured product. Competition from imports of similar perch species has been an ongoing problem over the years, with incidences of mis-labelling frequently cited. This, however, provides an opportunity for Yellow perch producers to emphasize the locally grown aspects of their products.
When planning a Yellow perch farming facility it will be necessary to calculate the carrying capacity of the system in order to estimate capital costs, projected production, revenues and input requirements (especially fingerlings and feed). At this point, an evaluation can begin in order to determine if the operation will be large enough to generate profits and if so, a market analysis can be undertaken. Markets must be available to accommodate production when it is ready for harvest because maintaining fish beyond a harvestable size requires excessive feed, labor and energy costs as well as unproductive use of facilities and capital.
Developing and maintaining committed relationships with both suppliers and buyers will be crucial, especially for large operations. No matter what the scale of production will be, Yellow perch producers must provide value through quality control, harvest scheduling and customer service. In turn, customers must also be willing to provide reliable outlets for marketable fish when the producer needs to move them.
Projected costs (variable, fixed, marketing and opportunity costs) must be compared to prevailing market prices for the sizes and quality of the fish that will be produced. Keep in mind economies of scale – a smaller operation will have higher per-fish costs and will require a number of small-volume, local markets that are willing and able to pay higher prices. When a small operation loses a customer, alternatives may be limited or nonexistent. Input suppliers (feed, fingerlings and equipment) must be reliable and trustworthy, even when larger customers are competing with your operation. Considerable attention must be paid to projected feed requirements – who will supply it, at what cost, and in what quantities will it be delivered? Bulk delivery only makes sense if the entire quantity will be used before its quality begins to deteriorate. However, if buying feed in bags instead of bulk deliveries, costs of production will automatically go up.
Because of their comparatively small size at harvest, as many as six fingerlings may be required to produce one pound of marketable Yellow perch. Feed trained fingerlings may account for up to half of production costs if purchased from other producers. Additionally, the limited and extremely seasonal availability of fingerlings requires careful planning for both production and marketing schedules as they are grown to a harvestable size. Having a number of production units stocked at different densities may help generate regular harvests of uniform product under these circumstances. This, however, may also require a larger initial investment and the need to compete in different markets (with larger, established producers) in order to justify investment costs.
Small scale Yellow perch production may not be profitable without a competitive edge in local markets gained through accessibility, customer service and logistics. On-site processing and sales may improve revenues, but these approaches usually involve excessive focus on permits, licenses, labor and liability insurance. Nonetheless, any number of marketing campaigns can be developed with local retail partners ranging from in-store product demonstrations, to visits by local school groups, to targeted marketing through on-line, print and radio media that serve communities accustomed to purchasing live or fresh fish. The tradition of the Friday night fish fry among consumers that are familiar with Yellow perch offers a marketing opportunity that is unavailable for other aquaculture producers throughout the U.S.
Prepared by C. Greg Lutz, Louisiana State University Agricultural Center