Welfare considerations specific to flatfish species in aquaculture including turbot, sole, and flounder.
Flatfish welfare in aquaculture requires recognizing these species as fundamentally different from the pelagic fish (salmon, trout) that most welfare standards were developed for. As benthic resting animals, flatfish have space needs measured in floor area, not tank volume. High stocking densities that allow multiple layers of fish — common in some turbot operations — prevent the natural benthic resting posture that these fish require. Aggression and skin damage at high density indicate welfare costs that also affect product quality through lesions and blemishes. The development of flatfish-specific welfare standards within aquaculture certification frameworks, recognizing their distinct behavioral ecology, represents an important gap in current welfare coverage. Consumer demand for certified premium flatfish products can drive welfare improvement through supply chain pressure where regulation lags.