Can Foraging for Earthworms Significantly Reduce Global Famine in a Catastrophe?

• Published in: Biomass (Basel, Switzerland) Switzerland), 2024-07, Vol.4 (3), p.765-783
• Main Authors: Miller, Henry, Mulhall, James, Pfau, Lou Aino, Palm, Rachel, Denkenberger, David C.
• Format: Article
• Language: English
• Subjects: earthworms; existential risk; foraging; global catastrophic risk; nuclear winter; resilient food
• ISSN: 2673-8783; 2673-8783
• DOI: 10.3390/biomass4030043

Earthworms are a resilient group of species thriving in varied habitats through feeding on decaying organic matter, and are therefore predicted to survive an abrupt sunlight reduction scenario, e.g., a nuclear winter. In this study, the feasibility and cost-effectiveness of foraging earthworms to reduce global famine in such a scenario with or without global catastrophic infrastructure loss was considered. Previously reported earthworm extraction methods (digging and sorting, vermifuge application, worm grunting, and electroshocking) were analysed, along with scalability, climate-related barriers to foraging, and pre-consumption processing requirements. Estimations of the global wild earthworm resource suggest it could provide three years of the protein needs of the current world human population, at a median cost of USD 353·kg−1 dry carbohydrate equivalent or a mean cost of USD 1200 (90% confidence interval: 32–8500)·kg−1 dry carbohydrate equivalent. At this price, foraging would cost a median of USD 185 to meet one person’s daily caloric requirement, or USD 32 if targeted to high-earthworm-biomass and low-labour-cost regions; both are more expensive than most existing resilient food solutions. While short-term targeted foraging could still be beneficial in select areas given its quick ramp-up, earthworms may bioaccumulate heavy metals, radioactive material, and other contaminants, presenting a significant health risk. Overall, earthworm foraging cannot be recommended as a scalable resilient food solution unless further research addresses uncertainties regarding cost-effectiveness and food safety.