The COVID-19 pandemic disrupted aquaculture supply chains globally, creating welfare crises from overcrowding and market collapse, while also generating lessons about biosecurity principles applicable to fish disease management.
The COVID-19 market collapse created acute welfare problems for fish held in sea cages beyond optimal size and density while markets were closed. Oversize fish in crowded conditions experience elevated stress, aggression, and increased disease susceptibility. The inability to harvest on schedule meant welfare problems compounded over weeks. The pandemic also demonstrated that biosecurity measures that prevent staff from reaching farms can prevent timely welfare intervention. Lessons for aquaculture welfare include: maintaining harvest flexibility, developing remote monitoring capacity, and building supply chain resilience that does not leave animals welfare-vulnerable when markets collapse.