Yangtze River Dolphin
The Yangtze River dolphin is just one of the names given to a functionally extinct species of dolphin which lived in the Yangzte River in China. It is also known as the Chinese river dolphin and the Baiji.
Its current conservation status is ‘critically endangered, possibly extinct’ but there has not been even an alleged sighting of one since 2007. The industrialization of China put a huge strain on the river systems as they were relied on as methods of transport, sources of food and ways of generating electricity. The baiji were caught in fishing nets, trapped in hydroelectric dams and hunted for their meat continually over a period of years. They could not reproduce at rates quick enough to replenish their population numbers.
In 2006 the species was declared to be functionally extinct, meaning that it would take huge reported sightings to save the species from certain extinction. This is the first recorded instance of the extinction of a relatively well-studied dolphin species.
Before they died out, baiji were believed to have mated in the first 6 months of the year with most calves being born between the months of February and April. The Gestation period lasted around 11 months and, as with most dolphin species, females gave birth to just one calf at a time. Females tended to wait 2 years before having another calf, meaning that each female gave birth approximately every 3 years.
When they were born, baiji calves measured nearly 3 feet in length and were nursed by their mothers for the first two years of their lives. The male Yangtze River Dolphin would reach sexual maturity around the age of 4 and the female would become fully fertile at 7 years of age. They weighed between 300 and 500 lb when fully grown to length of between 7 and 8 feet. They were relatively fast swimmers, especially for river dolphins, and could reach speeds of 37 miles per hour if they felt threatened.
The extinction of this species has served as an example and a warning. There are now far more conservation projects underway throughout the world to try and prevent the same fate for other species of river dolphins which are particularly vulnerable. As rural communities start to industrialize, the neighboring wildlife is not always their primary concern, but charities and conservation trusts are trying to change this in order to allow communities to grow in a sustainable and environmentally-friendly manner.
Yangtze River Dolphin