Bighead, silver, and common carp introduced to North American waterways are threatening native fish populations through competition and habitat modification.
Invasive carp welfare interactions are complex: individual carp fare well in invaded waterways but drive native fish welfare decline through competition for food and habitat modification. Native fish communities adapted to clear-water, vegetated conditions face welfare deterioration as carp turbidity reduces food availability and eliminates submerged vegetation. The welfare calculus favours native fish conservation — accepting welfare harms from carp control to prevent more diffuse and larger welfare harm to native species communities.