Environmental public health impacts of increasing crop production for aquaculture feed

Aquaculture has expanded over the past few decades to meet a growing demand for seafood and now produces half the seafood that people eat. It is estimated that 20% of fish caught globally is processed into fishmeal and fish oil, and the majority of both of these products are used as feed for certain types of farmed seafood. The fish used to make fishmeal and fish oil are forage fish (i.e., anchovies, herring, and sardines), which serve an important role near the base of the ocean's food web, and some populations are being fished at unsustainable rates. Overfishing threatens food security for coastal communities in developing countries, either because they rely on those fish or larger aquatic animals that feed on them. In order to lessen aquaculture's impact on forage fish there is increasing interest in reducing or eliminating fishmeal and fish oil in aquaculture feeds. This has led to significant resources, from private and public sources, being dedicated to research on alternative feed ingredients. A main area of research currently underway involves replacing fishmeal and fish oil with commodity crops such as soy and corn. Unless demand for these crops from other sectors decreases, which is unlikely due to increasing global demand for meat, this would lead to more production. Drawbacks of expanding production of industrially produced crops for aquaculture feed include deforestation, increased water and other resource use, runoff from pesticides and fertilizer, and other issues that impact ecologic and public health. During the talk, I will present information regarding: 1) Estimates of how much additional cropland would be needed to supply aquaculture feed for key species if a reduction or complete replacement of fishmeal and fish oil was implemented; and 2) How the increased crop production could impact environmental public health.