A Circular Protein Infrastructure for the Pacific and Southeast Asia.

Abstract Global aquaculture depends heavily on fishmeal and fish oil derived from wild forage fish such as anchovy, sardine, herring, and menhaden. These species are experiencing severe biomass declines driven by climate change, overfishing, and ecosystem instability. As a result, aquaculture supply chains in the Pacific and Southeast Asia face increasing volatility, rising feed costs, and heightened risk of systemic collapse. This paper proposes a fully integrated fish–insect–wastewater treatment infrastructure designed to stabilize protein supply, reduce dependence on wild forage fish, and alleviate ecological pressure on the world’s oceans. By combining wastewater‑derived organic inputs, black soldier fly (BSF) bioconversion, and aquaculture systems optimized for insect‑based feeds, this circular model creates a resilient, decentralized, and sustainable protein economy for the Pacific Rim and Southeast Asia. The system not only ensures continuous feed availability for aquaculture companies but also reduces nutrient pollution, supports agricultural productivity, and mitigates predator–prey conflict in marine ecosystems. By converting recovered nitrogen and phosphorus into controlled frass-based soil amendments, the model can also help reduce excess fertilizer runoff from farming systems into rivers, lakes, and coastal waters. This approach represents a scalable pathway toward global ocean recovery and long‑term food security. The proposed infrastructure is evaluated across four dimensions: feed security for aquaculture producers, nutrient recovery from wastewater systems, reduction of agricultural fertilizer runoff, and ecological relief for forage-fish-dependent marine food webs. The paper argues that these dimensions are mutually reinforcing rather than separate policy goals: wastewater treatment supplies recoverable nutrients, insect bioconversion converts those nutrients into feed inputs and frass fertilizer, agricultural reuse reduces nutrient losses to waterways, and aquaculture adoption reduces extraction pressure on wild forage fish.