Deaths of the endangered whales


Mystery killer behind tragic right whale deaths likely identified

Melissa Breyer (@MelissaBreyer) Science / Animals


© Andrea Chirife/Southern Right Whale Health Monitoring Program

Deaths of the endangered whales, mostly young calves, leapt 10-fold from 2005 to 2014. No one knew why until possibly now.

In 2005, something dreadful and very unusual started happening around Peninsula Valdes, an important calving ground for southern right whales on the coast of Argentina. Dead whales started washing ashore, many of them small calves younger than three months old; especially troubling given that females do not become sexually mature until ten years old and give birth to a single calf after a year of gestation. The average number of right whale deaths per year at this spot leapt from fewer than six per year before to 65 per year from 2005 to 2014. When TreeHugger wrote about it in 2010, we called it one of the largest die-offs of great whales ever recorded.

But now scientists may have cornered a suspect. The potential perpetrator? Blooms of toxic algae. Read more.