Amazon river dolphins (boto) are among the world's most enigmatic cetaceans, living in one of the most biodiverse freshwater systems on Earth. They face growing threats from fishing conflicts, habitat degradation, and deliberate killing.
Amazon river dolphin welfare is impacted by a combination of deliberate killing and incidental harm from fishing operations and environmental degradation. Deliberate killing for bait — botos are targeted because their flesh is particularly attractive to the mota mota catfish — causes acute welfare harm that is also illegal under Brazilian law but insufficiently enforced. Net entanglement causes drowning deaths in cetaceans that require regular air access — the distress and duration of drowning in a large, cognitively sophisticated dolphin is significant. Mercury accumulation from mining creates chronic toxicological welfare harm whose full effects on wild dolphins are difficult to assess but include neurological dysfunction. As highly social, intelligent animals with complex cognitive lives, botos likely experience suffering from the chronic anthropogenic pressure on their population — reduced food availability, increased human contact, and habitat degradation represent welfare stressors beyond the acute events that are more easily documented.