Except for bucolic scenes of fishing on rivers meandering across the Midwest and Great Plains, most people don't equate fish with that region, at least not huge catches of commercial fish. However, as long ago as 1996, "traders in the 'futures pit' of the Minneapolis Grain Exchange were shouting and signaling bids and offers for spring wheat, white wheat, white shrimp and black tiger shrimp" (Weber 1996). Moreover, the shrimp being traded in Minneapolis was of interest to the local trading office of the Thai government (Weber 1996); Thai food depends heavily on shrimp, so finding it at commodity prices is important to the Thai people.
Naturally, this scene would not have been possible except that it is no longer necessary to harvest shrimp from warm coastal waters where they live naturally. Shrimp, as well as other shellfish and finned fish as well, are raised on inland 'farms' in an age-old process called aquaculture. Rediscovering this form of food production that goes back at least as far as ancient Egypt was a necessity; scientists not that by 1996, human per capital fish consumption has reached 13 kilograms per person, a figure "unlikely to be met by wild harvesting alone" (Weber 1006). In addition, the United Nations once estimated that aquaculture would double by 2100 to meet the demands of an expanding population; indeed, in the United States, aquaculture had increased at 15% per year between 1980 and 1996 (Weber 1996).
History of aquaculture
In ancient China, aquaculture was practiced, with information about it coming from manuscripts dating to the 5th century B.C. Egyptian hieroglyphs of the Middle Kingdom (2052-1786 B.C.) reveal that the society had attempted intensive cultivation of fish. The ancient Romans cultivated oysters; in fact, the Roman culture of oysters is the form of aquaculture that has continued almost unchanged to the present, although most other forms differed then from the way fish and shellfish are raised now (History of Aquaculture Web site, undated).
In earlier times, aquaculture generally involved harvesting young fish or shellfish and "transferring them to an artificially created environment that is favorable to their growth" (History of Aquaculture Web site, undated). In China, carp was the favored fish; for the Egyptians and Romans, it was any hardy species that could survive the transfer to culture ponds (History of Aquaculture Web site, undated).
Modern forms of aquaculture were first practiced when, in 1733, a German farmer gathered fish eggs, fertilized them, and then grew and raised the hatchlings successfully. The process he employed was collecting male and female trout when they were ready to spawn, pressing the sperm and eggs from their bodies, and mixing them under favorable conditions. Then, when the fertilized eggs hatched, the fishling were taken to tanks or ponds where they were fed and could grow, protected, to maturity (History of Aquaculture Web site, undated).
While relatively prevalent fresh-water fish such as rainbow trout were the only targets of U.S. aquaculture for many years, as scientists learned more about fish life cycles and how to encourage egg production, fish farmers expanded into other commercial fish varieties, even into salt-water fishes. Still, because of the difficulty and cost of the science and the ponds, until recently, only luxury fish -- salmon, trout and shrimp -- were raised. However, that "trend is changing as new technologies allow for efficient and cost effective cultivation of non-luxury cheap foodfish" (History of Aquaculture Web site, undated).
History of Midwest aquaculture
The experience of other countries in salmon production was likely an impetus to establishing the Midwest/Great Plains aquaculture business. According to Weber (1996):
Between 1981 and 1991, production of Atlantic salmon in floating cages off Norway, Canada and several other countries leapt from 22 million pounds to nearly 530 million pounds, or about one quarter of all salmon consumed around the world, while farms off British Columbia, Chile and Japan produced millions of pounds of Pacific salmon.
The increase in worldwide production was in response to the challenge presented by increasingly popular seafood restaurants. Because fish is so perishable, the restaurants themselves were asking where they could obtain a constant supply of fresh fish in varieties consumers preferred. "Far more than in any other restaurant segment, the seafood operator's success depends on how well he does at buying product. Procurement has always been complicated by pricing and supply fluctuations" (Casper 1991). At that time, if they could, restaurants switched from menus featuring scarce and high-priced North Atlantic species such as cod to more abundant Pacific and South American varieties such as "South American corvina, Hawaiian kajiki or blue marlin, striped marlin, ono or wahoo, yellowfin tuna, golden tilefish, and skate" (Casper 1991). Lack of consumer familiarity with those varieties had limited their appeal however, but, according to restaurant industry observers, aquaculture "made a huge impact on availability and pricing of shrimp, salmon, catfish, and trout" (Casper 1991), all of which are familiar names. In addition, the National Fisheries Institute said other farm-raised fish it expected to play a big market role were "tilapia or Nile perch, hybrid striped bass, and sturgeon" (Casper, 1991). The potential for farm-raised fish leaves room for the wild varieties, too, however. Rector, in a Knight-Ridder News Service report, noted that some consumers avoid farm-raised fish because of their fears of environmental damage, while others prefer wild fish for the flavor and absence of artificial feeding regimens often needed to produce the same color flesh as is present in wild fish (Rector, 2002).
For these consumers, the specter of genetically engineered game fish would cause alarm, as well. However, in 1988, Sports Illustrated reported that it was possible those same meandering rivers that attract sportfishermen might be stocked with farm-raised "super fish."
Game fishing in the 1990s may call to mind a more unusual image, like that of a 100-pound chinook that has been injected with cattle growth hormone genes. Spurred by global research in aquaculture, U.S. biologists are manipulating genes and chromosomes in hopes of creating 'superfish' for the table and the den wall (Thornton, 1988).
One of the major funders for a project to create 'transgenic' walleyes by the summer of 1989 was the Minnesota State Legislature, which supported research on inserting and extra growth hormone gene into walleye eggs. The legislature hoped "hopes the superfish will someday spark a tourist bonanza" (Thornton, 1988). One of the reported aims of the project was finding away to turn the gene off so that, when the transgenic fish was released into the wild, it would act like a normal fish, but still offer "hatchery efficiency -- getting more fish for the buck" (Thornton, 1988).
By 1988, aquaculture had already provided the Midwest with several varieties of 'designer fish' including "experimental crossbreeds, from tiger trout (a female brown trout-male brook trout crossbreed) and splake (female lake trout and male brook trout) to the ultra-aggressive result of the cross of a bluegill and a sunfish (which were) already thriving in the wild" (Thornton, 1988).
Another sportfish research thrust that resulted in fish opponents of genetic modification might call monsters concerned "potentially giant chinooks" stocked in Lake Michigan by Michigan and Wisconsin. These were sterilized chinooks that a never receive the brain signal that tells wild chinook when to spawn and die; this allows the energy otherwise used for reproduction to produce growth. However, a University of Wisconsin computer model predicted these fish could easily grow to four times their normal size before dying of other causes (Thornton, 1988). While the researchers in this study were not unaware of the ethical ramifications of their work, it is clear that raising fish on farms is one thing; putting even non-transgenic fish into waterways where they don't belong can cause problems; these will be explained in the section about aquaculture problems, below. And indeed, the superchinook would not be the only aquaculture disaster that ever struck the Midwest. Arguably, modern aquaculture can help rectify the release, in the 1800s, of carp into Midwest waters. Then, the intention was to create a better fisheries industry on the rivers and states "fought over the limited supply of carp eggs. Before long, though, the carp had taken over many of the waters in which they had been planted, displacing such valuable game fish as bass" (Thornton, 1988).
Current status of Midwestern aquaculture
By 2002, several pressures on Midwestern economies had caused aquaculture to once again gain attention from farmers and the press. Hannah (2002) reported that "More and more Ohio farmers are turning to aquaculture as a way to supplement their income and shield their farms from falling crop prices, fickle weather and other financial pressures." Chicken farmers have entered the aquaculture market because they already had water, and they had the infrastructure in place, as well as the market. One of these former chicken farmers now produces 500 pounds of tilapia each week in northwest Ohio, selling it to restaurants and grocery stores in Columbus, Dayton and Toledo (Hannah, 2002).