Salmon Farming: The Whole Story
November 4, 2013
Review By Dorothee Schreiber
Salmon Farming : The Whole Story is not the “whole story,” but it is certainly the standard story that fish farmers like to tell of an industry maligned by “constant high-profile public opposition” (18). Peter Robson presents himself as an honest broker who will provide readers with the facts they need to form their own opinions. He covers a wide range of topics, from the development of the industry on the coast, to how fish are reared, how fish feeds are produced, how fish farming sites are chosen, and how farmed fish are treated for disease. Approximately half the book is devoted to explaining the impacts of fish farming on wild fish and marine habitat through the transfer of disease, the release of waste and contaminants, and fish farm escapes. The final chapter evaluates the health impacts of eating farmed fish.
Despite this apparently thorough treatment of the topic, Robson uncritically presents a claim frequently made by fish farmers themselves: that it is in the operators’ own best economic interest to operate on a sustainable basis. He also assumes that the high density of regulation surrounding the industry means that the regulations are ecologically and medically relevant. Robson makes much of the absence of proof for fish farming’s negative environmental impact, but such proof will continue to be elusive as fish farming on BC’s coast continues as one giant, unreplicated experiment confounded by many other factors such as overfishing, logging, urbanization, and climate change. Robson greatly downplays fish farming’s environmental impacts without examining how the burden of proof, and the power to operate in spite of great uncertainty are socially distributed, or how the networks of research and regulation are socially organized.
This book does a great disservice to readers by relying on folksy notions of biology to construct common-sense arguments about fish farming and the environment. For example, Robson uses a familiar survival-of-the-fittest narrative to imply that the wild fish who succumb to sea lice infection were stressed and unhealthy and destined to die anyway. In arguing thus, Robson sets up fish farming as a model for nature, of which the wild populations are only bad copies. Fish farmers, he claims, put their fish in the pens “100 percent pathogen free”(65), while migrating wild fish are sources of infection in the ocean (153, 161) and on the spawning grounds, where “disease is rampant” (116). From this point of view, the fish farm is also a field site for ecological study – a vantage point and a point of comparison, from which ecological changes can be confidently assessed. Robson therefore takes fish farmers’ observations – such as their highly contextualized experiences with farmed fish, disease loadings, treatment options, and seasonal runoff conditions (161) – as reliable comments on the state of the environment.
The most troubling example of this book’s tendency to misuse biological concepts is in its calculation of the transfer efficiency of fish feed to farmed fish production (107). Robson’s informants (a pair of fish feed manufacturers) claim this rate is around 88 percent. Such a rate is unheard-of in the mainstream ecological literature, where transfer efficiencies for fish and other vertebrates tend to be on the order of 10 percent or less. The calculation Robson presents assumes that farmed salmon are vastly more efficient than wild fish in converting food into body mass because they do not have to expend much energy to search for food, migrate or spawn. But Robson and his informants do not take into account any of the energy used to capture, manufacture, and transport farmed fish feed, and assume that the refuse from the process is not wasted because it can be used to feed animals in other livestock industries. This is creative ecological reasoning, to say the least.
The book is peppered with some interesting facts. Who would have thought that selenium deficiency in fish feed was nearly a showstopper in the early days of the BC salmon farming industry (34)? Or that the early maturation of male salmon – known as “jacking” in the wild – also takes place in the fish farm environment (75)?
For the most part, however, readers interested in an overview of salmon farming issues would be better served by reading A Stain Upon the Sea: West Coast Salmon Farming, by Stephen Hume, Alexandra Morton, Betty Keller, Rosella M. Leslie, Otto Langer, and Don Staniford, a volume that is openly critical of fish farming, but that is more honest in its assumptions and more careful in its treatment of government and industry facts, studies, and regulatory regimes.