Marine protected areas are conservation tools, but individual fish welfare within MPAs depends on fishing pressure at boundaries, collection for the aquarium trade, and physical habitat quality.
Marine protected areas benefit individual fish welfare by reducing fishing mortality, chronic disturbance from trawling, and habitat degradation. Well-enforced no-take MPAs allow fish populations to express fuller behavioural repertoires and recover from chronic anthropogenic stress. However, boundary effects — intensive fishing at MPA edges — can create high mortality zones for fish that move beyond protected waters. Climate change impacts on coral within MPAs increasingly threaten the habitat quality that makes protection meaningful. MPAs are necessary but insufficient without complementary climate action and boundary enforcement.