The Black Soldier Fly (Hermetia illucens; BSF) has gained attention as a potential alternative feed source for aquaculture of finfish, as the fly’s larvae have the ability to convert organic waste products into valuable fats and proteins that can be incorporated into aquaculture diets. This has the potential to allow the aquaculture industry to sustainably grow, producing more fish-based protein into the future. With the global increased in aquaculture production and fish consumption has come an associated increase in fisheries by-products, such as inedible products. These fisheries by-products are considered high value due to the protein and fat content. Studies have found that the substrate on which BSF are grown directly influence the fat and protein content of the BSF larvae. If BSF nutrient content can be manipulated by changing the diet fed to larvae, then perhaps incorporation of fisheries by-products would yield larvae with nutritional profiles targeted towards their use in aquafeeds. This would provide a mechanism to address growing fisheries waste management concerns and tailoring BSF insect meal product specific for feedstock purpose.
The study focused on the incorporation of fisheries by-products in BSF feeding substrate to assess any value-added potential to the final BSF product as it pertains to aquaculture feeds. We assessed inclusion fisheries by-products in the base substrate and as a finishing diet, described as feeding general organic waste (e.g., from horticulture) for most of the life cycle, with high-quality feed (e.g., fisheries products) in the critical time before harvest. St-Hilaire et al. (2007) showed that omega fatty acid profiles can be enhanced by supplementing a cow manure-based diet of larval BSF with processed fish waste (e.g., fish carcasses from canneries) in the last 24hrs of larval feeding (Figure 1.). Barroso et al. (2017), further supported this finding with the addition of omega-3 lipids to BSF diets resulting in BSF meal with three times more omega-3’s than the control group. Finishing diets may allow the low-cost addition of high value food product (e.g., fish meal, or fish offal) resulting in high value insect meal. This would offer the potential to enhance the nutritional profile of BSF meal tailored for aquafeeds, with the potential of higher inclusion levels. This study determined how the incorporation of fisheries by-product influences BSF larval nutrient composition, as well as the potential to utilise BSF technology to address the growing concerns around increased quantities of fisheries wastes and by-products. The ability to utilise waste products from aquaculture in BSF farming promotes circularity, thereby reducing inefficiencies through reduction of resources from a range of industries required to produce aquafeeds.