April 2, 2009
Good News for Irrawaddy Dolphins
Another celebratory first from Hawaii: at the first international conference on protected areas for marine mammals, biologists working in Bangladesh reported that they found a thriving population of 6,000 Irrawaddy dolphins, a mother lode considering that marine mammal experts had feared the species was vulnerable to extinction. And although the dolphins are doing much better than predicted, scientists say they still need to be protected from the rising threat of fishing net entanglement (i.e.,bycatch) and global warming, which will likely raise sea levels and change the river flows, shrinking the species’ range. Other river dolphin and porpoise species have not fared so well. (Though it’s important to note that Irrawaddy dolphins aren’t true river dolphins but oceanic dolphins that live in brackish water.) In 2007, the baiji, a river dolphin in China’s Yangtze River was pronounced extinct as a result of the enormous amount of human activity in the area. And who could forget the adorable and critically endangered vaquita marina, a porpoise in the Gulf of California, whose remaining 150-member population is also threatened by fishing nets.