Dolphins, orcas, and other cetaceans held in marine parks experience profound welfare deprivation. Their complex social and cognitive needs are incompatible with captive environments, no matter how large the tank.
The welfare case against captive cetaceans is compelling. Orcas in particular have cognitive and social complexity that make any tank environment fundamentally inadequate. Family disruption during capture or through captive breeding causes lasting psychological harm. Chronic boredom, incompatible social groupings, and the inability to hunt or navigate natural environments cause measurable welfare deficits. Sanctuary facilities that allow cetaceans to live in ocean pens with natural water, prey, and more natural social groupings represent a meaningful improvement over tanks, though they remain imperfect solutions for animals with such vast natural ranges.