The 24th of October is International Freshwater Dolphin Day! Although we might think of dolphins as creatures of the sea, there are actually five species of dolphin that live exclusively in freshwater habitats.
Freshwater dolphins can be found in specific rivers and deltas in Asia and South America. The boto or Amazon river dolphin is the biggest of these, with males reaching up to two and a half metres long. Born dark grey, these dolphins become rose-tinted as they grow into adulthood, earning them the nickname ‘pink river dolphin’!
Unlike their marine relatives, freshwater dolphins have little to no blubber, since they’re adapted to living in warmer, shallow water. Rivers can often be quite muddy and murky, so freshwater species like the Ganges river dolphin only have tiny eyes, relying instead on their highly-developed hearing that works both in air and underwater.
Sadly, human activity is having a terrible impact on these unusual cetaceans. The baiji or Yangtze river dolphin hasn’t been seen since 2004 and is now believed to be extinct, due to heavy industrial use of their river in China. This is thought to be the first case of a dolphin species driven to extinction by humans.
Whether in rivers or oceans, it’s clear that dolphins are facing the same devastating issues: fishing bycatch, vessel traffic, pollution, habitat destruction and climate change. It’s vital that we join forces across the world to protect all cetacean species from these major threats.
Header photo of botos or Amazon river dolphins by Daria Zekert, via Getty Images.