Net negative nutrient yields in a bait-consuming fishery

Abstract

Abstract Efforts to achieve sustainable food systems are impeded by inefficiencies associated with the use of agricultural land and resources to grow feed for animals, rather than food for direct consumption by people. In contrast, the unspoken assumption about fisheries, which are a key source of protein and micronutrients, is that they are inherently net-positive producers of food, as they appear to require no intentional inputs of resources that could otherwise be directly consumed by people. However, this assumption may not hold true for all fisheries. One such fishery is the Maine fishery for American lobster (Homarus americanus), which for decades has used substantial amounts of Atlantic herring (Clupea harengus) as bait in its traps. Here, we evaluate the Maine lobster fishery’s production of a suite of nutrients both before and after consideration of its use of Atlantic herring as bait. Despite several sources of uncertainty, our results indicate that the Maine lobster fishery has likely been a net consumer of multiple nutrients in recent years. This stems from both the scale of herring bait use in the lobster fishery, and from herring’s comparatively high edible biomass yield and nutrient content. To our knowledge, this is the first example of a fishery consuming more nutrients, through bait, than it produces through landings. Identifying and addressing such inefficiencies will ensure that fisheries contribute to sustainable food production.