Yes, dolphins are endangered and it’s because of human activity.
According to the IUCN Red List of Threatened Species, out of 41 dolphin species, five species and six subspecies are endangered. When a species is considered endangered, they fall into either the Critically Endangered, Endangered, or Vulnerable category.
Why are dolphins endangered? Let’s look into five different species and learn why.
1. Atlantic Humpback dolphin
Considered “critically endangered,” the Atlantic Humpback dolphin’s greatest threat to survival is incidental bycatch by fisheries. Since the species is found in shallow waters off the coast of West Africa, they’re extremely vulnerable to the gillnets set by local fishermen. Atlantic Humpback dolphins are also susceptible to the “marine bushmeat” trade, as well as marine pollution. Today, it’s estimated that only 1,500 individuals are left in the wild.
2. Amazon River dolphin
Known as the “pink river dolphin,” one of the Amazon River dolphin’s main threats to survival are deliberate killings for fish bait or predator control. In Brazil, poachers illegally hunt and kill the dolphins and use their fatty blubber as bait to catch piracatinga, a carnivorous catfish. To help curb the illegal hunt and protect dolphins, the Brazilian government introduced a moratorium on catching piracatinga from July 2015- July 2021. Currently, the dolphin is considered “endangered.”
3. Baiji dolphin
The last documented sighting of the Baiji dolphin was in 2002. Since then, only unconfirmed sightings made by students and local fisherman have been reported. Currently considered “critically endangered,” the Baiji dolphin will soon be considered “extinct,” making the species the first dolphin species to be driven to extinction by humans. Found only in the Yangtze River in China, Baiji dolphins were frequently under threat from incidental bycatch by fisheries.
4. Maui dolphin
With only 55 Maui dolphins left in the wild, this New Zealand dolphin species is labeled as “critically endangered.” Known as the smallest dolphin in the world, Maui dolphins are also slow breeders (a female has only one calf every 2-3 years) and they become sexually mature when they’re 7-9 years old. What’s their biggest threat? You guessed it—incidental bycatch by fisheries.
5. South Asian River dolphin
Divided into two subspecies (the Ganges river dolphin and the Indus river dolphin), it’s estimated that the total population of the species is less than 5,000. Unlike fishing practices, which are the main threats for endangered dolphins, the South Asian River dolphin is threatened by water development projects such as dams and irrigation barrages. As a result, populations are fragmented, and habitats are reduced. The IUCN labels the dolphin species as “endangered.”