Amazon River Dolphin (Boto) Conservation and Welfare

The Amazon river dolphin, or boto, is the world's largest freshwater cetacean and faces growing threats from mercury poisoning, bycatch, and deliberate killing for use as fishing bait. Conservation urgency is increasing rapidly.

Key Facts

Amazon river dolphins (Inia geoffrensis), also called botos or pink dolphins, inhabit the Amazon and Orinoco river systems of South America.
They were classified as Endangered by the IUCN in 2018 after previously being listed as Data Deficient; populations have declined by approximately 94% in some survey areas.
A key driver of recent decline is the deliberate killing of botos to use as bait for the mota catfish (Calophysus macropterus), a commercially valuable species.
Mercury from illegal gold mining bioaccumulates in boto tissue; affected individuals show neurological damage, reproductive failure, and immune suppression.
Botos are highly intelligent and curious, often approaching boats and interacting with fishers — a behaviour that has historically made them targets for harassment and killing.
In Amazonian indigenous cultures, botos have mythological significance and have historically been protected from killing; breakdown of traditional taboos has contributed to increased persecution.
Legal protection for botos exists in Brazil, Colombia, Peru, and Venezuela, but enforcement in remote river systems is extremely limited.
Acoustic pollution from boat traffic disrupts boto echolocation and social communication, affecting foraging efficiency.

Welfare Considerations

Boto welfare is compromised by multiple converging threats. Mercury poisoning from artisanal gold mining causes neurological damage that impairs the dolphins' ability to echolocate, navigate, and socialise — a form of chronic neurological suffering. Deliberate killing for fishing bait involves trapping dolphins in nets and killing them — an acutely painful and frightening experience for highly intelligent, social animals. Bycatch entanglement causes drowning deaths — distressing for air-breathing cetaceans that can experience hypoxia and panic before death. The scale of decline documented in recent surveys — 94% in some areas — means the cumulative welfare harm to the boto population is enormous. Mercury-contaminated waterways also harm the indigenous human communities that depend on fish as a primary protein source, creating an interlinked human and animal welfare crisis.

What You Can Do

Support the Instituto Mamiraua and WWF-Brazil programmes working on boto conservation and monitoring in the Amazon.
Avoid gold jewellery from suppliers that cannot certify mercury-free mining practices — artisanal gold mining is a primary driver of Amazonian mercury pollution.
Advocate for stronger enforcement of boto protection laws and harsher penalties for deliberate killing.
Engage with campaigns to regulate the mota catfish trade, which drives the boto bait market.
Raise awareness of the boto's rapidly deteriorating conservation status — it is one of the world's least-known cetacean conservation emergencies.