Because of their massive size, blue whales are known as the ocean's "gentle giants." They are vital to the ocean ecosystem, but their numbers are declining. In this episode, 2016 Pew marine fellow Dr. Asha de Vos unpacks the significance of blue whales to our ocean's health and how effects from human activity, such as increased shipping and the whale-watching industry, influence the blue whale's population and migratory pattern.

Since this episode first aired in 2019, de Vos has continued conservation efforts through her organization, Oceanswell, and has advanced research on the effects of plastic pollution in Sri Lanka.